butterknife

Class ButterKnife

java.lang.Object

butterknife.ButterKnife

public final class ButterKnife
extends java.lang.Object

View "injection" utilities. Use this class to simplify finding views and attaching listeners by injecting them.

Injecting views from your activity is as easy as:

 public class ExampleActivity extends Activity {
    @InjectView(R.id.title) EditText titleView;
    @InjectView(R.id.subtitle) EditText subtitleView;

    @Override protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.example_activity);
     ButterKnife.inject(this);
   }
 }
 

Injection can be performed directly on an activity, a view, or a dialog. Alternate objects to inject can be specified along with an activity, view, or dialog.

Group multiple views together into a List or array.

  @InjectViews({R.id.first_name, R.id.middle_name, R.id.last_name})
 List nameViews;
 

There are three convenience methods for working with view collections:

• apply(List, Action) – Applies an action to each view.
• apply(List, Setter, Object) – Applies a setter value to each view.
• apply(List, Property, Object) – Applies a property value to each view.

To inject listeners to your views you can annotate your methods:

  @OnClick(R.id.submit) void onSubmit() {
   // React to button click.
 }
 

Any number of parameters from the listener may be used on the method.

  @OnItemClick(R.id.tweet_list) void onTweetClicked(int position) {
   // React to tweet click.
 }
 

Be default, views are required to be present in the layout for both field and method injections. If a view is optional add the @Optional annotation.

  @Optional @InjectView(R.id.title) TextView subtitleView;
 

See Also:

InjectView, InjectViews, OnCheckedChanged, OnClick, OnEditorAction, OnFocusChange, OnItemClick, OnItemLongClick, OnItemSelected, OnLongClick, OnPageChange, OnTextChanged, OnTouch

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ButterKnife.Action<T extends android.view.View> An action that can be applied to a list of views.
static class	ButterKnife.Finder DO NOT USE: Exposed for generated code.
static interface	ButterKnife.Setter<T extends android.view.View,V> A setter that can apply a value to a list of views.

Method Summary

Modifier and Type	Method and Description
static <T extends android.view.View> void	apply(java.util.List<T> list, ButterKnife.Action<? super T> action) Apply the specified action across the list of views.
static <T extends android.view.View,V> void	apply(java.util.List<T> list, ButterKnife.Setter<? super T,V> setter, V value) Set the value using the specified setter across the list of views.
static <T extends android.view.View,V> void	apply(java.util.List<T> list, android.util.Property<? super T,V> setter, V value) Apply the specified value across the list of views using the property.
static <T extends android.view.View> T	findById(android.app.Activity activity, int id) Simpler version of Activity.findViewById(int) which infers the target type.
static <T extends android.view.View> T	findById(android.view.View view, int id) Simpler version of View.findViewById(int) which infers the target type.
static void	inject(android.app.Activity target) Inject annotated fields and methods in the specified Activity.
static void	inject(android.app.Dialog target) Inject annotated fields and methods in the specified Dialog.
static void	inject(java.lang.Object target, android.app.Activity source) Inject annotated fields and methods in the specified target using the source Activity as the view root.
static void	inject(java.lang.Object target, android.app.Dialog source) Inject annotated fields and methods in the specified target using the source Dialog as the view root.
static void	inject(java.lang.Object target, android.view.View source) Inject annotated fields and methods in the specified target using the source View as the view root.
static void	inject(android.view.View target) Inject annotated fields and methods in the specified View.
static void	reset(java.lang.Object target) Reset fields annotated with @InjectView and @InjectViews to null.
static void	setDebug(boolean debug) Control whether debug logging is enabled.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

setDebug

public static void setDebug(boolean debug)

Control whether debug logging is enabled.

inject

public static void inject(android.app.Activity target)

Inject annotated fields and methods in the specified Activity. The current content view is used as the view root.

Parameters:

target - Target activity for field injection.

inject

public static void inject(android.view.View target)

Inject annotated fields and methods in the specified View. The view and its children are used as the view root.

Parameters:

target - Target view for field injection.

inject

public static void inject(android.app.Dialog target)

Inject annotated fields and methods in the specified Dialog. The current content view is used as the view root.

Parameters:

target - Target dialog for field injection.

inject

public static void inject(java.lang.Object target,
                          android.app.Activity source)

Inject annotated fields and methods in the specified target using the source Activity as the view root.

Parameters:

target - Target class for field injection.

source - Activity on which IDs will be looked up.

inject

public static void inject(java.lang.Object target,
                          android.view.View source)

Inject annotated fields and methods in the specified target using the source View as the view root.

Parameters:

target - Target class for field injection.

source - View root on which IDs will be looked up.

inject

public static void inject(java.lang.Object target,
                          android.app.Dialog source)

Inject annotated fields and methods in the specified target using the source Dialog as the view root.

Parameters:

target - Target class for field injection.

source - Dialog on which IDs will be looked up.

reset

public static void reset(java.lang.Object target)

Reset fields annotated with @InjectView and @InjectViews to null.

This should only be used in the onDestroyView method of a fragment.

Parameters:

target - Target class for field reset.

apply

public static <T extends android.view.View> void apply(java.util.List<T> list,
                                                       ButterKnife.Action<? super T> action)

Apply the specified action across the list of views.

apply

public static <T extends android.view.View,V> void apply(java.util.List<T> list,
                                                         ButterKnife.Setter<? super T,V> setter,
                                                         V value)

Set the value using the specified setter across the list of views.

apply

public static <T extends android.view.View,V> void apply(java.util.List<T> list,
                                                         android.util.Property<? super T,V> setter,
                                                         V value)

Apply the specified value across the list of views using the property.

findById

public static <T extends android.view.View> T findById(android.view.View view,
                                                       int id)

Simpler version of View.findViewById(int) which infers the target type.

findById

public static <T extends android.view.View> T findById(android.app.Activity activity,
                                                       int id)

Simpler version of Activity.findViewById(int) which infers the target type.