1. This content is available free on created by
http://RailsForZombies.org

2. Feel free to delete this slide
This means you can use the If you need to charge some
content: money
* You can modify / remix it to run an event which uses this
content
it can not be profitable. i.e. You
should only be charging enough
However: to cover costs.
* You can’t charge money for it
If profit is involved, Envy Labs
* You must keep the attribution deserves a small cut,
probably
don’t you think? Maybe even
consider having Envy Labs teach
it in person perhaps?
Email => Gregg@EnvyLabs.com
This content is available free on created by
http://RailsForZombies.org

3. Recommendations for running
•You’ll need 3-4 for Zombies through the
a Live Rails hours to get
tutorial, with enough time for labs
Tutorial
•Present these slides, then give students
20-30
minutes do do the exercises on
RailsForZombies.org
•Have students go through TryRuby.org
ahead of time,
if they’re not familiar with Ruby
•If you’re not comfortable with presenting
this material
feel free to just play the videos on the
website and Feel free to delete this slid
not use these slides available free on created by
This content is
http://RailsForZombies.org

4. Recommendations for creating
•Make each episode a separate video, not one long
one. a
•If possible, don’t use slides
video with these your laptop microphone, use
a
USB Microphone like: http://amzn.to/eHTMSJ
•Seeing your face is more entertaining then just
watching code. Please insert yourself into the
content.
•Keynote allows you to “Record Slideshow”, which is
good for
pacing the timing of the slides (not audio though).
You can
then export video with that timing. You’d then
take this into
another video editor. (this is how you to delete this slid
Feel free export with
animations) content is available free on
This created by
If you need an editor suggestion: Screenflow
http://RailsForZombies.org

5. An Introduction to
Rails
Episode #1
This content is available free on created by
http://RailsForZombies.org

6. Prerequisites:
TryRuby.org

7. Episode #1
Deep in the

9. FOR ZO
F MB IES!!
!

10. CRU
D

11. CRU
D
tweets

12. CRU
D
tweets
Rows {
(we have 4)

13. CRU
Columns D
Rows {
(we have 4)
{
tweets
(we have 3)

14. CRU
D

15. CRU
D
id

16. CRU
D
id status

17. CRU
D
id status zombie

18. CRU
D
id status zombie
Zombie Challenge #1
Retrieve a hash of the tweet with id =
3

19. CRU
D
id status zombie
Zombie Challenge #1
Retrieve a hash of the tweet with id =
3
Result
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }

20. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }

21. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]

22. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]
"I just ate some delicious brains"

23. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]
"I just ate some delicious brains"
puts b[:zombie]

24. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]
"I just ate some delicious brains"
puts b[:zombie]
"Jim"

25. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]
"I just ate some delicious brains"
puts b[:zombie]
"Jim"
puts b[:zombie] + " said " + b[:status]

26. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]
"I just ate some delicious brains"
puts b[:zombie]
"Jim"
puts b[:zombie] + " said " + b[:status]
"Jim said I just ate some delicious brains"

27. CRU
Hash D
Series of key value pairs
b = { :status => "I just ate some delicious brains",
:zombie => "Jim" }
puts b[:status]
"I just ate some delicious brains"
puts b[:zombie]
"Jim"
puts b[:zombie] + " said " + b[:status]
"Jim said I just ate some delicious brains"

28. CRU
D

29. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

30. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3

31. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)

32. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)
puts t[:id]

33. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)
puts t[:id] 3

34. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)
puts t[:id] 3
puts t[:status]

35. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)
puts t[:id] 3
puts t[:status] "I just ate some delicious brains."

36. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)
puts t[:id] 3
puts t[:status] "I just ate some delicious brains."
puts t[:zombie]

37. CRU
tweets D
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
ombie Challenge #1
Retrieve a hash of the tweet with id = 3
Answer t = Tweet.find(3)
puts t[:id] 3
puts t[:status] "I just ate some delicious brains."
puts t[:zombie] "Jim"

38. CRU
t = Tweet.find(3)
D
puts t[:id]
puts t[:status]
puts t[:zombie]

39. CRU
t = Tweet.find(3)
D
puts t[:id] puts t.id
Sam
puts t[:status]
eA
puts t[:zombie]
s

40. CRU
t = Tweet.find(3)
D
puts t[:id] puts t.id
Sam
puts t[:status] puts t.status
eA
puts t[:zombie]
s

41. CRU
t = Tweet.find(3)
D
puts t[:id] puts t.id
Sam
puts t[:status] puts t.status
eA
puts t[:zombie] puts t.zombie
s

42. CRU
t = Tweet.find(3)
D
puts t[:id] puts t.id
Sam
puts t[:status] puts t.status
eA
puts t[:zombie] puts t.zombie
s
Answer puts t.id 3
puts t.status "I just ate some delicious brains."
puts t.zombie "Jim"

43. CRU
t = Tweet.find(3)
D

44. CRU
t = Tweet.find(3)
D
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

45. CRU
t = Tweet.find(3)
D
Pluralize
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

46. C
R
U
D

47. Create
Read
Update
Delete

48. Create
Read
Update
Delete

49. t = Tweet.new
Create t.status = "I <3 brains."
t.save
Read
Update
Delete

50. t = Tweet.new
Create t.status = "I <3 brains."
t.save
Read Tweet.find(3)
Update
Delete

51. t = Tweet.new
Create t.status = "I <3 brains."
t.save
Read Tweet.find(3)
t = Tweet.find(3)
Update t.zombie = "EyeballChomper"
t.save
Delete

52. t = Tweet.new
Create t.status = "I <3 brains."
t.save
Read Tweet.find(3)
t = Tweet.find(3)
Update t.zombie = "EyeballChomper"
t.save
t = Tweet.find(3)
Delete t.destroy

53. Create Syntax
t = Tweet.new
t.status = "I <3 brains."
t.zombie = "Jim"
t.save

54. Create Syntax
the id .
t = Tweet.new
n’t set a lly
e do anu
t.status = "I <3 brains."
tic e w s set m
t.zombie = "Jim" No et
t.save he id g or us.
T f

55. Create Syntax
the id .
t = Tweet.new
n’t set a lly
e do anu
t.status = "I <3 brains."
tic e w s set m
t.zombie = "Jim" No et
t.save he id g or us.
T f
Alternate Syntax

56. Create Syntax
the id .
t = Tweet.new
n’t set a lly
e do anu
t.status = "I <3 brains."
tic e w s set m
t.zombie = "Jim" No et
t.save he id g or us.
T f
Alternate Syntax
t = Tweet.new(:status => "I <3 brains", :zombie => "Jim")
t.save

57. Create Syntax
the id .
t = Tweet.new
n’t set a lly
e do anu
t.status = "I <3 brains."
tic e w s set m
t.zombie = "Jim" No et
t.save he id g or us.
T f
Alternate Syntax
t = Tweet.new(:status => "I <3 brains", :zombie => "Jim")
t.save
Tweet.create(:status => "I <3 brains", :zombie => "Jim")

58. Read Syntax

59. Read Syntax
Tweet.find(2) # Returns a single item

60. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array

61. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet

62. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet

63. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet
Tweet.all # Returns all the tweets

64. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet
Tweet.all # Returns all the tweets
Tweet.count # Returns number of tweets

65. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet
Tweet.all # Returns all the tweets
Tweet.count # Returns number of tweets
Tweet.order(:zombie) # All ordered by zombie

66. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet
Tweet.all # Returns all the tweets
Tweet.count # Returns number of tweets
Tweet.order(:zombie) # All ordered by zombie
Tweet.limit(10) # Only 10 tweets

67. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet
Tweet.all # Returns all the tweets
Tweet.count # Returns number of tweets
Tweet.order(:zombie) # All ordered by zombie
Tweet.limit(10) # Only 10 tweets
Tweet.where(:zombie => "ash") # Only tweets by Ash

68. Read Syntax
Tweet.find(2) # Returns a single item
Tweet.find(3, 4, 5) # Returns an array
Tweet.first # Returns the first tweet
Tweet.last # Returns the last tweet
Tweet.all # Returns all the tweets
Tweet.count # Returns number of tweets
Tweet.order(:zombie) # All ordered by zombie
Tweet.limit(10) # Only 10 tweets
Tweet.where(:zombie => "ash") # Only tweets by Ash
Tweet.where(:zombie => "ash").order(:zombie).limit(10)
method chaining

69. Update Syntax
t = Tweet.find(3)
t.zombie = "EyeballChomper"
t.save

70. Update Syntax
t = Tweet.find(3)
t.zombie = "EyeballChomper"
t.save
t = Tweet.find(2)
t.attributes = {
:status => "Can I munch your eyeballs?",
:zombie => "EyeballChomper"
}
t.save

71. Update Syntax
t = Tweet.find(3)
t.zombie = "EyeballChomper"
t.save
t = Tweet.find(2)
t.attributes = {
:status => "Can I munch your eyeballs?",
:zombie => "EyeballChomper"
}
t.save
t = Tweet.find(2)
t.update_attributes(
:status => "Can I munch your eyeballs?",
:zombie => "EyeballChomper"
)

72. Delete Syntax
t = Tweet.find(2)
t.destroy

73. Delete Syntax
t = Tweet.find(2)
t.destroy
Tweet.find(2).destroy

74. Delete Syntax
t = Tweet.find(2)
t.destroy
Tweet.find(2).destroy
Tweet.destroy_all

75. Zombie
http://railsforzombies.org
Stop when you reach the video for Lab 2
Don’t worry about watching any of the videos
Download the slides so you can remember the syntax

76. An Introduction to
Rails
Episode #2
This content is available free on created by
http://RailsForZombies.org

77. Chapter 2
Models taste like chicken

78. Model
s

79. Model
t = Tweet.find(3)
Tweet s

80. Model
t = Tweet.find(3)
Tweet s
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

81. Model
t = Tweet.find(3)
Tweet s
?
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

82. Model
t = Tweet.find(3)
Tweet s
app/models/tweet.rb
class Tweet < ActiveRecord::Base
end
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

83. Model
Tweet s
app/models/tweet.rb
class Tweet < ActiveRecord::Base
end
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

84. Model
Tweet s
app/models/tweet.rb
class Tweet < ActiveRecord::Base
end
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

85. Model
Tweet s
app/models/tweet.rb
class Tweet < ActiveRecord::Base
end
Maps the class to the
tweets table
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

86. Model
Tweet s
app/models/tweet.rb
class Tweet < ActiveRecord::Base
end
Maps the class to the
tweets table
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

87. Model
app/models/tweet.rb
class Tweet < ActiveRecord::Base s
end
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

88. Model
app/models/tweet.rb
class Tweet < ActiveRecord::Base s
end
t = Tweet.find(3)
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

89. Model
app/models/tweet.rb
class Tweet < ActiveRecord::Base s
end
t = Tweet.find(3)
class
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

90. Model
app/models/tweet.rb
class Tweet < ActiveRecord::Base s
end
t = Tweet.find(3)
class
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

91. Model
app/models/tweet.rb
class Tweet < ActiveRecord::Base s
end
instance of Tweet t = Tweet.find(3)
Tweet #3
class
tweets
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

92. Validations?
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

93. Validations?
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
t = Tweet.new
t.save

94. Validations?
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash
5
t = Tweet.new
t.save

95. Valida
tio
app/models/tweet.rb ns
class Tweet < ActiveRecord::Base
end

96. Valida
tio
app/models/tweet.rb ns
class Tweet < ActiveRecord::Base
validates_presence_of :status
end

97. Valida
tio
app/models/tweet.rb ns
class Tweet < ActiveRecord::Base
validates_presence_of :status
end
> t = Tweet.new
=> #<Tweet id: nil, status: nil, zombie: nil>

98. Valida
tio
app/models/tweet.rb ns
class Tweet < ActiveRecord::Base
validates_presence_of :status
end
> t = Tweet.new
=> #<Tweet id: nil, status: nil, zombie: nil>
> t.save
=> false

99. Valida
tio
app/models/tweet.rb ns
class Tweet < ActiveRecord::Base
validates_presence_of :status
end
> t = Tweet.new
=> #<Tweet id: nil, status: nil, zombie: nil>
> t.save
=> false
> t.errors
=> {:status=>["can't be blank"]}

100. Valida
tio
app/models/tweet.rb ns
class Tweet < ActiveRecord::Base
validates_presence_of :status
end
> t = Tweet.new
=> #<Tweet id: nil, status: nil, zombie: nil>
> t.save
=> false
> t.errors
=> {:status=>["can't be blank"]}
> t.errors[:status]
=> "can't be blank"

101. Valida
tio
ns

102. Valida
tio
validates_presence_of :status ns
validates_numericality_of :fingers
validates_uniqueness_of :toothmarks
validates_confirmation_of :password
validates_acceptance_of :zombification
validates_length_of :password, :minimum => 3
validates_format_of :email, :with => /regex/i
validates_inclusion_of :age, :in => 21..99
validates_exclusion_of :age, :in => 0...21,
:message => “Sorry you must be over 21”

103. Valida
tio
ns

104. te alidation Valida
Attribu V tio
validates :status, :presence => true
ns

105. te alidation Valida
Attribu V tio
validates :status, :presence => true
ns
validates :status, :length => { :minimum => 3 }

106. te alidation Valida
Attribu V tio
validates :status, :presence => true
ns
validates :status, :length => { :minimum => 3 }
validates :status, :presence => true, :length => { :minimum => 3 }

107. te alidation Valida
Attribu V tio
validates :status, :presence => true
ns
validates :status, :length => { :minimum => 3 }
validates :status, :presence => true, :length => { :minimum => 3 }
:presence => true
:uniqueness => true
:numericality => true
:length => { :minimum => 0, :maximum => 2000 }
:format => { :with => /.*/ }
:inclusion => { :in => [1,2,3] }
:exclusion => { :in => [1,2,3] }
:acceptance => true
:confirmation => true

108. el a ti o nship s
Because they always travel in packs

109. Relatio
tweets
nship
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

110. Relatio
tweets
nship
id status zombie
1 Where can I get a good bite to eat? Ash
2 My left arm is missing, but I don't care. Bob
3 I just ate some delicious brains. Jim
4 OMG, my fingers turned green. #FML Ash

111. Relatio
tweets
nship
id status
1 Where can I get a good bite to eat?
2 My left arm is missing, but I don't care.
3 I just ate some delicious brains.
4 OMG, my fingers turned green. #FML

112. Relatio
tweets
nship
id status
1 Where can I get a good bite to eat?
2 My left arm is missing, but I don't care.
3 I just ate some delicious brains.
4 OMG, my fingers turned green. #FML
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

113. Relatio
tweets
nship
id status
1 Where can I get a good bite to eat?
2 My left arm is missing, but I don't care.
3 I just ate some delicious brains.
4 OMG, my fingers turned green. #FML
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

114. Relatio
tweets
nship
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

115. Relatio
tweets
nship
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

116. Relatio
tweets
nship
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
5 Your eyelids taste like bacon. 2
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

117. Relatio
tweets
nship
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
5 Your eyelids taste like bacon. 2
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

118. Relatio
tweets
nship
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
5 Your eyelids taste like bacon. 2
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

119. tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

120. A Tweet
tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

121. A Tweet belongs to
tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

122. A Tweet belongs to a Zombie
tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

123. A Tweet belongs to a Zombie
app/models/tweet.rb
class Tweet < ActiveRecord::Base
end
tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

124. A Tweet belongs to a Zombie
app/models/tweet.rb
class Tweet < ActiveRecord::Base
belongs_to :zombie
end
Singular tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

125. A Tweet belongs to a Zombie A Zombie
app/models/tweet.rb
class Tweet < ActiveRecord::Base
belongs_to :zombie
end
Singular tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

126. A Tweet belongs to a Zombie A Zombie has many
app/models/tweet.rb
class Tweet < ActiveRecord::Base
belongs_to :zombie
end
Singular tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

127. A Tweet belongs to a Zombie A Zombie has many Tweets
app/models/tweet.rb
class Tweet < ActiveRecord::Base
belongs_to :zombie
end
Singular tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

128. A Tweet belongs to a Zombie A Zombie has many Tweets
app/models/tweet.rb app/models/zombie.rb
class Tweet < ActiveRecord::Base class Zombie < ActiveRecord::Base
belongs_to :zombie
end end
Singular tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

129. A Tweet belongs to a Zombie A Zombie has many Tweets
app/models/tweet.rb app/models/zombie.rb
class Tweet < ActiveRecord::Base class Zombie < ActiveRecord::Base
belongs_to :zombie has_many :tweets
end end
Plural
Singular tweets
id status zombie_id
1 Where can I get a good bite to eat? 1
2 My left arm is missing, but I don't care. 2
3 I just ate some delicious brains. 3
4 OMG, my fingers turned green. #FML 1
zombies
id name graveyard
1 Ash Glen Haven Memorial Cemetery
2 Bob Chapel Hill Cemetery
3 Jim My Father’s Basement

130. Relatio
nship
A Tweet belongs to a Zombie

131. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">

132. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t = Tweet.create(:status => "Your eyelids taste like bacon.", :zombie => z)
=> #<Tweet id: 5, status: "Your eyelids taste like bacon.", zombie_id: 2>

133. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t = Tweet.create(:status => "Your eyelids taste like bacon.", :zombie => z)
=> #<Tweet id: 5, status: "Your eyelids taste like bacon.", zombie_id: 2>
> t.zombie
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">

134. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t = Tweet.create(:status => "Your eyelids taste like bacon.", :zombie => z)
=> #<Tweet id: 5, status: "Your eyelids taste like bacon.", zombie_id: 2>
> t.zombie
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t.zombie.name
=> "Bob"

135. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t = Tweet.create(:status => "Your eyelids taste like bacon.", :zombie => z)
=> #<Tweet id: 5, status: "Your eyelids taste like bacon.", zombie_id: 2>
> t.zombie
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t.zombie.name
=> "Bob"
> ash = Zombie.find(1)
=> #<Zombie id: 1, name: "Ash", graveyard: "Glen Haven Cemetery">

136. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t = Tweet.create(:status => "Your eyelids taste like bacon.", :zombie => z)
=> #<Tweet id: 5, status: "Your eyelids taste like bacon.", zombie_id: 2>
> t.zombie
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t.zombie.name
=> "Bob"
> ash = Zombie.find(1)
=> #<Zombie id: 1, name: "Ash", graveyard: "Glen Haven Cemetery">
> ash.tweets.count
=> 4

137. Relatio
nship
A Tweet belongs to a Zombie
> z = Zombie.find(2)
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t = Tweet.create(:status => "Your eyelids taste like bacon.", :zombie => z)
=> #<Tweet id: 5, status: "Your eyelids taste like bacon.", zombie_id: 2>
> t.zombie
=> #<Zombie id: 2, name: "Bob", graveyard: "Chapel Hill Cemetery">
> t.zombie.name
=> "Bob"
> ash = Zombie.find(1)
=> #<Zombie id: 1, name: "Ash", graveyard: "Glen Haven Cemetery">
> ash.tweets.count
=> 4
> ash.tweets
=> [#<Tweet id: 1, status: "Where can I get a good bite to eat?", zombie_id: 1>,
#<Tweet id: 4, status: "OMG, my fingers turned green. #FML", zombie_id: 1>]

138. Zombie

139. An Introduction to
Rails
Episode #
This content is available free on created by
http://RailsForZombies.org

140. Chapter 3
The View ain’t always pretty
I’m so gonna
eat his brains

141. Vie
Our Application Stack ws

142. Vie
Our Application Stack ws
4 Components

143. Vie
Our Application Stack ws
Models
4 Components

144. Vie
Our Application Stack ws
Views
Models
4 Components

145. Views

146. Views
zombie_twitter
app

147. Views
zombie_twitter
app
views

148. Views
zombie_twitter
app
views
zombies
tweets

149. Views
zombie_twitter
app
views
zombies
tweets
index.html.erb
show.html.erb

150. Views
zombie_twitter
app
views
zombies
List all tweets
tweets
index.html.erb
show.html.erb

151. Views
zombie_twitter
app
views
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

152. Views
Edible Rotting Bodies
zombie_twitter
app
views
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

153. Views
Edible Rotting Bodies
Embedded Ruby
zombie_twitter
Ruby inside HTML
app
views
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

154. Show a tweet

155. Show a tweet

156. Show a tweet
<% ... %>
Evaluate Ruby

157. Show a tweet
<% ... %>
Evaluate Ruby
<%= ... %>
Eval and print result

158. Show a tweet
<% ... %>
Evaluate Ruby
<%= ... %>
Eval and print result
/app/views/tweets/show.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
</body></html>

159. Show a tweet
<% ... %>
Evaluate Ruby
<%= ... %>
Eval and print result
/app/views/tweets/show.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>
</body></html>

160. Show a tweet
<% ... %>
Evaluate Ruby
<%= ... %>
Eval and print result
/app/views/tweets/show.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
FYI, This code
<% tweet = Tweet.find(1) %>
sucks a little..
<h1><%= tweet.status %></h1> (for 2 reasons)
<p>Posted by <%= tweet.zombie.name %></p>
</body></html>

161. Show a tweet
<% ... %>
Evaluate Ruby
<%= ... %>
Eval and print result
/app/views/tweets/show.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>
</body></html>

162. Show a tweet
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
</body></html>
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

163. Show a tweet
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
<%= yield %>
</body></html>
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

164. Views
zombie_twitter
app
views
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

165. Views
zombie_twitter
app
views
layouts
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

166. Views
zombie_twitter
app
views
The main layout
layouts
application.html.erb
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

167. Additional Layout Components
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>Twitter for Zombies</title>
</head>
<body>
<img src="/images/twitter.png" />
<%= yield %>
</body></html>

168. Additional Layout Components
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>Twitter for Zombies</title>
</head>
<body>
<img src="/images/twitter.png" />
<%= yield %>
</body></html>

169. Additional Layout Components
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>Twitter for Zombies</title>
<%= stylesheet_link_tag :all %>
</head>
<body>
<img src="/images/twitter.png" />
<%= yield %>
</body></html>

170. Additional Layout Components
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>Twitter for Zombies</title>
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
</head>
<body>
<img src="/images/twitter.png" />
<%= yield %>
</body></html>

171. Additional Layout Components
/app/views/layouts/
application.html.erb
<!DOCTYPE html>
<html>
<head>
<title>Twitter for Zombies</title>
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>
</head>
<body>
<img src="/images/twitter.png" />
<%= yield %>
</body></html>

172. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>

173. Additional Layout Components
<%= stylesheet_link_tag :all %>
Includ
styles e all
heets
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>

174. Additional Layout Components
<%= stylesheet_link_tag :all %>
Includ
zombie_twitter styles e all
public
heets
stylesheets
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>

175. Additional Layout Components
<%= stylesheet_link_tag :all %>
Includ
zombie_twitter styles e all
public
heets
stylesheets
Renders
<link href="/stylesheets/scaffold.css" media="screen" rel="stylesheet" type="text/css" />
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>

176. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>

177. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
Includ
e d ef
ault J
S
<%= csrf_meta_tag %>

178. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
Includ
zombie_twitter e d ef
ault J
public S
javascripts
<%= csrf_meta_tag %>

179. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
Includ
zombie_twitter e d ef
ault J
public S
javascripts
Renders
<script Proto
src="/javascripts/prototype.js" type="text/javascript"></script>
<script type
src="/javascripts/effects.js" type="text/javascript"></script>
Javas
<script
Fram c r ip t
src="/javascripts/dragdrop.js" type="text/javascript"></script>
<script
<script ework
src="/javascripts/controls.js" type="text/javascript"></script>
src="/javascripts/rails.js" type="text/javascript"></script>
<script src="/javascripts/application.js" type="text/javascript"></script>
<%= csrf_meta_tag %>

180. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>

181. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>
Zombie Hacker
<form Site
target="http://yoursite.co
m">
Think Your Site
comm
spam ent

182. Additional Layout Components
<%= stylesheet_link_tag :all %>
<%= javascript_include_tag :defaults %>
<%= csrf_meta_tag %>
Zombie Hacker
<form Site
target="http://yoursite.co
m">
Think Your Site
comm
Renders spam ent
<meta name="csrf-param" content="authenticity_token"/>
<meta name="csrf-token" content="I+d..jI="/>
Automatically adds this to forms

183. Root path and images

184. Root path and images
http://ZombieTwitter.com/[something]

185. Root path and images
http://ZombieTwitter.com/[something]
zombie_twitter lic
ub to
public /p
in e go
xi sts rwis
stylesheets
I f e othe
javascripts
e it, Ra ils
images us
Example
<img src="/images/twitter.png" />

186. Adding a Link

187. Adding a Link
/app/views/tweets/show.html.erb
...
<p>Posted by <%= tweet.zombie.name %></p>

188. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l

189. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l
<%= %>

190. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l
<%= link_to %>

191. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l
<%= link_to tweet.zombie.name %>
Link Text

192. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l
<%= link_to tweet.zombie.name , zombie_path(tweet.zombie) %>
Link Text Link Path (URL)

193. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l
<%= link_to tweet.zombie.name , zombie_path(tweet.zombie) %>
Link Text Link Path (URL)
Renders <a href="/zombies/1">Ash</a>

194. Adding a Link
/app/views/tweets/show.html.erb
bi ea
...
ez om
ak ink
<p>Posted by <%= tweet.zombie.name %></p>
M l
<%= link_to tweet.zombie.name , zombie_path(tweet.zombie) %>
Link Text Link Path (URL)
Renders <a href="/zombies/1">Ash</a>
We can also write as
<%= link_to tweet.zombie.name, tweet.zombie %>
Link Text Object to Show

196. Method
link_to with it?
y ou use
ons can
W hat opti

197. Method
link_to with it?
y ou use
ons can
W hat opti
1. Look in the source

198. Method
link_to with it?
y ou use
ons can
W hat opti
1. Look in the source
Command Line

199. Method
link_to with it?
y ou use
ons can
W hat opti
1. Look in the source
Command Line
git clone http://github.com/rails/rails.git

200. Method
link_to with it?
y ou use
ons can
W hat opti
1. Look in the source
Command Line
git clone http://github.com/rails/rails.git
cd rails

201. Method
link_to with it?
y ou use
ons can
W hat opti
1. Look in the source
Command Line
git clone http://github.com/rails/rails.git
cd rails
Open your editor and search for “def link_to”

202. Method
link_to with it?
y ou use
ions can
W hat op t
2. Look at
api.rubyonrails.org
(and search for link_to)

203. http://

204. Method
link_to with it?
y ou use
ions can
W hat op t

205. Method
link_to with it?
y ou use
ions can
W hat op t
3. API Dock
(online Ruby and Rails docs)
http://apidock.com/rails

207. Method
with it?
link_to
y ou use
ions can
W hat op t

208. Method
with it?
link_to
y ou use
ions can
W hat op t
4. Rails Searchable API Doc
(local download or online)
http://railsapi.com/

209. http://railsapi.com/

213. <%= link_to @tweet.zombie.name, @tweet.zombie, :confirm => "Are you sure?" %>

214. <%= link_to @tweet.zombie.name, @tweet.zombie, :confirm => "Are you sure?" %>

215. Views
zombie_twitter
app
views
The main layout
layouts
application.html.erb
zombies
List all tweets
tweets
index.html.erb
View a tweet
show.html.erb

216. Views
List Tweets

217. Views
List Tweets

218. Views
List Tweets
/app/views/tweets/index.html.erb

219. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr>

220. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr>
<% Tweet.all.each do |tweet| %>

221. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr>
<% Tweet.all.each do |tweet| %>
<tr>
<td><%=
<td><%=
</tr>
<% end %>
</table>

222. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr>
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= tweet.status %></td>
<td><%=
</tr>
<% end %>
</table>

223. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr>
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= tweet.status %></td>
<td><%= tweet.zombie.name %></td>
</tr>
<% end %>
</table>

224. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr> What they return
<% Tweet.all.each do |tweet| %> Tweet class
<tr>
<td><%= tweet.status %></td>
<td><%= tweet.zombie.name %></td>
</tr>
<% end %>
</table>

225. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr> What they return
<% Tweet.all.each do |tweet| %> Tweet class
<tr>
<td><%= tweet.status %></td>
<td><%= tweet.zombie.name %></td> Tweet.all array of tweets
</tr>
<% end %>
</table>

226. Views
List Tweets
/app/views/tweets/index.html.erb
<h1>Listing tweets</h1>
<table>
<tr>
<th>Status</th>
<th>Zombie</th>
</tr> What they return
<% Tweet.all.each do |tweet| %> Tweet class
<tr>
<td><%= tweet.status %></td>
<td><%= tweet.zombie.name %></td> Tweet.all array of tweets
</tr>
<% end %> tweet single tweet
</table>

227. Create Links Views
/app/views/tweets/index.html.erb
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= tweet.status %></td>
<td><%= tweet.zombie.name %></td>
</tr>
<% end %>

228. Create Links Views
/app/views/tweets/index.html.erb
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= tweet.zombie.name %></td>
</tr>
<% end %>

229. Create Links Views
/app/views/tweets/index.html.erb
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
</tr>
<% end %>

230. Empty Table?Views
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
</tr>
<% end %>

231. Empty Table?Views
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
</tr>
<% end %>

232. Empty Table?Views
<% Tweet.all.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
</tr>
<% end %>

233. Empty Table?Views
<% Tweet.all.each do |tweet| %>
...
<% end %>

234. Empty Table?Views
<% tweets = Tweet.all %>
<% .each do |tweet| %>
...
<% end %>

235. Empty Table?Views
<% tweets = Tweet.all %>
<% tweets.each do |tweet| %>
...
<% end %>

236. Empty Table?Views
<% tweets = Tweet.all %>
<% tweets.each do |tweet| %>
...
<% end %>
<% if tweets.size == 0 %>
<em>No tweets found</em>
<% end %>

237. Empty Table?Views
<% tweets = Tweet.all %>
<% tweets.each do |tweet| %>
...
<% end %>
<% if tweets.empty? %>
<em>No tweets found</em>
<% end %>

238. Empty Table?Views
<% tweets = Tweet.all %>
<% tweets.each do |tweet| %>
...
<% end %>
<% if tweets.empty? %>
<em>No tweets found</em>
<% end %>

239. Edit & Delete Links?

240. Edit & Delete Links?

241. Edit & Delete Links?
<% tweets.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
</tr>
<% end %>

242. Edit & Delete Links?
<% tweets.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
<td><%= link_to "Edit", edit_tweet_path(tweet) %></td>
</tr>
<% end %>

243. Edit & Delete Links?
<% tweets.each do |tweet| %>
<tr>
<td><%= link_to tweet.status, tweet %></td>
<td><%= link_to tweet.zombie.name, tweet.zombie %></td>
<td><%= link_to "Edit", edit_tweet_path(tweet) %></td>
<td><%= link_to "Delete", tweet, :method => :delete %></td>
</tr>
<% end %>

244. All links for Tweets

245. All links for Tweets
<%= link_to "<link text>", <code> %>

246. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new

247. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new

248. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new

249. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new
These paths n
tweet = Tweet.find(1) eed a
tweet

250. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new
These paths n
tweet = Tweet.find(1) eed a
tweet
Action Code The URL Generated
Show a tweet tweet /tweets/1
Edit a tweet edit_tweet_path(tweet) /tweets/1/edit
Delete a tweet tweet, :method => :delete /tweets/1

251. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new
These paths n
tweet = Tweet.find(1) eed a
tweet
Action Code The URL Generated
Show a tweet tweet /tweets/1
Edit a tweet edit_tweet_path(tweet) /tweets/1/edit
Delete a tweet tweet, :method => :delete /tweets/1

252. All links for Tweets
<%= link_to "<link text>", <code> %>
Action Code The URL Generated
List all tweets tweets_path /tweets
New tweet form new_tweet_path /tweets/new
These paths n
tweet = Tweet.find(1) eed a
tweet
Action Code The URL Generated
Show a tweet tweet /tweets/1
Edit a tweet edit_tweet_path(tweet) /tweets/1/edit
Delete a tweet tweet, :method => :delete /tweets/1

253. Zombie

254. An Introduction to
Rails
Episode #
This content is available free on created by
http://RailsForZombies.org

255. Chapter 4 r ai ns
b
v
Controllers must be eaten

256. Vie
Our Application Stack ws

257. Vie
Our Application Stack ws
Views
Models
4 Components

258. Vie
Our Application Stack ws
Views
Controllers
Models
4 Components

259. Show a tweet
/app/views/tweets/show.html.erb
<!DOCTYPE html>
<html>
<head><title>Twitter for Zombies</title></head>
<body>
<img src="/images/twitter.png" />
FYI, This code
<% tweet = Tweet.find(1) %>
sucks a little..
<h1><%= tweet.status %></h1> (we’ll fix it later)
<p>Posted by <%= tweet.zombie.name %></p>
</body></html>

260. /app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

261. Request
/tweets/1
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

262. Request
/tweets/1
Controller
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

263. zombie_twitter
app Request
controllers /tweets/1
tweets_controller.rb
/app/controllers/tweets_controller.rb
Controller
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

264. zombie_twitter
app Request
controllers tweets
/tweets/1
tweets_controller.rb
tweets
/app/controllers/tweets_controller.rb
Controller
/app/views/tweets/show.html.erb
tweets
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

265. Request
/tweets/1
/app/controllers/tweets_controller.rb
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

266. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
...
end
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

267. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
end
end
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

268. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
end
end
/app/views/tweets/show.html.erb
show
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

269. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
end
end
/app/views/tweets/show.html.erb
<% tweet = Tweet.find(1) %>
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

270. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

271. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

272. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

273. Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
What about
<h1><%= tweet.status %></h1> variable scope?
<p>Posted by <%= tweet.zombie.name %></p>

274. Instance Variable Request
/tweets/1
@
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

275. Instance Variable Request
/tweets/1
@
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
@ tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

276. Instance Variable Request
/tweets/1
@
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
@ tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= @ tweet.status %></h1>
<p>Posted by <%= tweet.zombie.name %></p>

277. Instance Variable Request
/tweets/1
@
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
@ tweet = Tweet.find(1)
end
end
/app/views/tweets/show.html.erb
<h1><%= @ tweet.status %></h1>
<p>Posted by <%= @ tweet.zombie.name %></p>

278. Render Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
@ tweet = Tweet.find(1)
end
end
/app/views/tweets/status.html.erb
<h1><%= @ tweet.status %></h1>
<p>Posted by <%= @ tweet.zombie.name %></p>

279. Render Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
@ tweet = Tweet.find(1)
end
end
/app/views/tweets/status.html.erb
<h1><%= @ tweet.status %></h1>
<p>Posted by <%= @ tweet.zombie.name %></p>

280. Render Request
/tweets/1
/app/controllers/tweets_controller.rb
class TweetsController < ApplicationController
def show
@ tweet = Tweet.find(1)
end
end
/app/views/tweets/status.html.erb
<h1><%= @ tweet.status %></h1>
<p>Posted by <%= @ tweet.zombie.name %></p>