Butter Knife

配置

compile 'com.jakewharton:butterknife:8.4.0'

在build.gradle中取消lint警告：

lintOptions {
  disable 'InvalidPackage'
}


ProGuard
-keep class butterknife.** { *; }
-dontwarn butterknife.internal.**
-keep class **$$ViewBinder { *; }

-keepclasseswithmembernames class * {
    @butterknife.* <fields>;
}

-keepclasseswithmembernames class * {
    @butterknife.* <methods>;
}

使用

• @BindView findViewById()
  ButterKnife.bind(this, view);
  @BindView(R.id.user) EditText username;

  
  //activity
  class ExampleActivity extends Activity {
    @BindView(R.id.title) TextView title;
    @BindView(R.id.subtitle) TextView subtitle;
    @BindView(R.id.footer) TextView footer;
  
    @Override public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.simple_activity);
      ButterKnife.bind(this);
      // TODO Use fields...
    }
  }
                 
  //non-activity
  public class FancyFragment extends Fragment {
    @BindView(R.id.button1) Button button1;
    @BindView(R.id.button2) Button button2;
  
    @Override 
    public View onCreateView(
                  LayoutInflater inflater, 
                  ViewGroup container, 
                  Bundle savedInstanceState) 
    {
      View view = inflater.inflate(R.layout.frag, container, false);
      ButterKnife.bind(this, view);
      // TODO Use fields...
      return view;
    }
    
      @Override 
      public void onDestroyView() {
      super.onDestroyView();
      unbinder.unbind();
    }
  }
  
  static class ViewHolder {
      @BindView(R.id.title) TextView name;
      @BindView(R.id.job_title) TextView jobTitle;
  
      public ViewHolder(View view) {
        ButterKnife.bind(this, view);
      }
    }
    
    
  //Controller
  ButterKnife.bind(this, activity)
  
  //
  merge inflate之后 或 onFinishInflate()
  

• @BindString 资源
  @BindString(R.string.login_error) String loginErrorMessage;
  @BindBool、@BindColor、@BindDimen、@BindDrawable、@BindInt、@BindString
• @BindViews 将多个views绑定到数组

  
  @BindViews({ R.id.first_name, R.id.middle_name, R.id.last_name }) 
  List<EditText> nameViews;    
  
  //在这个列表中每一个元素上进行调用
  ButterKnife.apply(nameViews, DISABLE);
  ButterKnife.apply(nameViews, ENABLED, false);
  ButterKnife.apply(nameViews, View.ALPHA, 0.0f);
  
  static final ButterKnife.Action<View> DISABLE = new ButterKnife.Action<View>() {
    @Override public void apply(View view, int index) {
      view.setEnabled(false);
    }
  };
  static final ButterKnife.Setter<View, Boolean> ENABLED = new ButterKnife.Setter<View, Boolean>() {
    @Override public void set(View view, Boolean value, int index) {
      view.setEnabled(value);
    }
  };
  

• @OnClick 监听器绑定

  
  @OnClick(R.id.submit)
  public void submit(View view) {
    // TODO submit data to server...
  }
  
  
  //All arguments to the listener method are optional.
  //参数可选
  @OnClick(R.id.submit)
  public void submit() {
    // TODO submit data to server...
  }
  
  
  //Define a specific type and it will automatically be cast.
  //参数类型识别
  @OnClick(R.id.submit)
  public void sayHi(Button button) {
    button.setText("Hello!");
  }    
  
  
  //Specify multiple IDs in a single binding for common event handling.
  //绑定多个id控件到同一个监听器上
  @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();
    }
  }
  
  
  
  //Custom views can bind to their own listeners by not specifying an ID.
  //自定义View绑定事件监听时无需ID：
  public class FancyButton extends Button {
    @OnClick
    public void onClick() {
      // TODO do something!
    }
  }
  

• unbind Fragments

  
  @Override 
  public void onDestroyView() {
      super.onDestroyView();
      unbinder.unbind();
  }
  

• 多回调方法

  
  //能够对监听器任何一个函数进行绑定
  @OnItemSelected(R.id.list_view)
  void onItemSelected(int position) {
    // TODO ...
  }
  
  //每一个注解都会绑定到一个默认的回调。可以指定callback参数
  @OnItemSelected(value = R.id.maybe_missing, callback = NOTHING_SELECTED)
  void onNothingSelected() {
    // TODO ...
  }
              

• @Nullable 忽视异常

  
  @Nullable 
  @BindView(R.id.might_not_be_there) TextView mightNotBeThere;
  
  @Optional 
  @OnClick(R.id.maybe_missing) void onMaybeMissingClicked() {
    // TODO ...
  }
              

• findById 免转换

  
  View view = LayoutInflater.from(context).inflate(R.layout.thing, null);
  TextView firstName = ButterKnife.findById(view, R.id.first_name);
  TextView lastName = ButterKnife.findById(view, R.id.last_name);
  ImageView photo = ButterKnife.findById(view, R.id.photo);