How to use ButterKnife, Lombok, and how these change the way you code :)

1. Android Opensources
Wooseong Kim (김우성)
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2. 1. ButterKnife
2. Lombok
3.Android Annotations
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3. ButterKnife?
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4. • http://jakewharton.github.io/butterknife/
• using Annotation Processing
• No more findViewById in Activity, View,
ListAdapter etc.
• Simplify click listeners
ButterKnife
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5. ButterKnife - before / at activity
class ExampleActivity extends Activity {
TextView title;
TextView subtitle;
TextView footer;
@Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.simple_activity);
title = (TextView) findViewById(R.id.title);
subtitle = (TextView) findViewById(R.id.subtitle);
footer = (TextView) findViewById(R.id.footer);
//TODO Use views...
}
}
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6. ButterKnife - after / at activity
class ExampleActivity extends Activity {
@InjectView(R.id.title)TextView title;
@InjectView(R.id.subtitle)TextView subtitle;
@InjectView(R.id.footer)TextView footer;
@Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.simple_activity);
ButterKnife.inject(this);
//TODO Use "injected" views...
}
}
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7. ButterKnife - after / at view
public class FancyFragment extends Fragment {
@InjectView(R.id.button1) Button button1;
@InjectView(R.id.button2) Button button2;
@OverrideView onCreateView(LayoutInflater inflater,ViewGroup container, Bundle
savedInstanceState) {
View view = inflater.inflate(R.layout.fancy_fragment, container, false);
ButterKnife.inject(this, view);
//TODO Use "injected" views...
return view;
}
}
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8. ButterKnife - after / at list adapter
public class MyAdapter extends BaseAdapter {
@Override publicView getView(int position,View view,ViewGroup parent) {
ViewHolder holder;
view = inflater.inflate(R.layout.whatever, parent, false);
holder = new ViewHolder(view);
holder.name.setText("John Doe");
// etc...
return convertView;
static classViewHolder {
@InjectView(R.id.title)TextView name;
@InjectView(R.id.job_title)TextView jobTitle;
publicViewHolder(View view) {
ButterKnife.inject(this, view);
}
}
}
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9. ButterKnife - onClick
@OnClick({ R.id.door1, R.id.door2, R.id.door3 })
public void pickDoor(DoorView door) {
if (door.hasPrizeBehind()) {
Toast.makeText(this, "You win!", LENGTH_SHORT).show();
} else {
Toast.makeText(this, "Try again", LENGTH_SHORT).show();
}
}
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10. Lombok ?
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11. • http://projectlombok.org/
• No more Getter / Setter!
Lombok
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12. Lombok - before
public class GetterSetterExample {
private int age = 10;
private String name;
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
protected void setName(String name) {
this.name = name;
}
}
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13. Lombok - after
public class GetterSetterExample {
@Getter @Setter private int age = 10;
@Setter(AccessLevel.PROTECTED) private String name;
}
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14. Android
Annotations ?
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15. Android Annotations - before
public class BookmarksToClipboardActivity extends Activity {
BookmarkAdapter adapter;
ListView bookmarkList;
EditText search;
BookmarkApplication application;
Animation fadeIn;
ClipboardManager clipboardManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(FLAG_FULLSCREEN, FLAG_FULLSCREEN);
setContentView(R.layout.bookmarks);
bookmarkList = (ListView) findViewById(R.id.bookmarkList);
search = (EditText) findViewById(R.id.search);
application = (BookmarkApplication) getApplication();
fadeIn = AnimationUtils.loadAnimation(this, anim.fade_in);
clipboardManager = (ClipboardManager) getSystemService(CLIPBOARD_SERVICE);
View updateBookmarksButton1 = findViewById(R.id.updateBookmarksButton1);
updateBookmarksButton1.setOnClickListener(new OnClickListener() {
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16. Android Annotations - after
@NoTitle
@Fullscreen
@EActivity(R.layout.bookmarks)
public class BookmarksToClipboardActivity extends Activity {
BookmarkAdapter adapter;
@ViewById ListView bookmarkList;
@ViewById EditText search;
@App BookmarkApplication application;
@RestService BookmarkClient restClient;
@AnimationRes Animation fadeIn;
@SystemService ClipboardManager clipboardManager;
@AfterViews // instead of onCreate() (called after injecting)
void initBookmarkList() {
adapter = new BookmarkAdapter(this);
bookmarkList.setAdapter(adapter);
}
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17. To be continued…
• Robolectric (2.2+) -Testing
- http://robolectric.org/
• Otto - Event handler using bus
- http://square.github.io/otto/
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18. Thank you!
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