ImageButton


public class ImageButton
extends ImageView

java.lang.Object
   ↳ android.view.View
     ↳ android.widget.ImageView
       ↳ android.widget.ImageButton


Displays a button with an image (instead of text) that can be pressed or clicked by the user. By default, an ImageButton looks like a regular Button, with the standard button background that changes color during different button states. The image on the surface of the button is defined either by the android:src attribute in the <ImageButton> XML element or by the ImageView.setImageResource(int) method.

To remove the standard button background image, define your own background image or set the background color to be transparent.

To indicate the different button states (focused, selected, etc.), you can define a different image for each state. E.g., a blue image by default, an orange one for when focused, and a yellow one for when pressed. An easy way to do this is with an XML drawable "selector." For example:

 <?xml version="1.0" encoding="utf-8"?>
 <selector xmlns:android="http://schemas.android.com/apk/res/android">
     <item android:state_pressed="true"
           android:drawable="@drawable/button_pressed" /> <!-- pressed -->
     <item android:state_focused="true"
           android:drawable="@drawable/button_focused" /> <!-- focused -->
     <item android:drawable="@drawable/button_normal" /> <!-- default -->
 </selector>

Save the XML file in your project res/drawable/ folder and then reference it as a drawable for the source of your ImageButton (in the android:src attribute). Android will automatically change the image based on the state of the button and the corresponding images defined in the XML.

The order of the <item> elements is important because they are evaluated in order. This is why the "normal" button image comes last, because it will only be applied after android:state_pressed and android:state_focused have both evaluated false.

See the Buttons guide.

XML attributes

See Button Attributes, View Attributes

Summary

Inherited XML attributes

Inherited constants

Inherited fields

Public constructors

ImageButton(Context context)
ImageButton(Context context, AttributeSet attrs)
ImageButton(Context context, AttributeSet attrs, int defStyleAttr)
ImageButton(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)

Public methods

CharSequence getAccessibilityClassName()

Return the class name of this object to be used for accessibility purposes.

PointerIcon onResolvePointerIcon(MotionEvent event, int pointerIndex)

Resolve the pointer icon that should be used for specified pointer in the motion event.

Protected methods

boolean onSetAlpha(int alpha)

Invoked if there is a Transform that involves alpha.

Inherited methods

Public constructors

ImageButton

Added in API level 1
public ImageButton (Context context)

Parameters
context Context

ImageButton

Added in API level 1
public ImageButton (Context context, 
                AttributeSet attrs)

Parameters
context Context

attrs AttributeSet

ImageButton

Added in API level 1
public ImageButton (Context context, 
                AttributeSet attrs, 
                int defStyleAttr)

Parameters
context Context

attrs AttributeSet

defStyleAttr int

ImageButton

Added in API level 21
public ImageButton (Context context, 
                AttributeSet attrs, 
                int defStyleAttr, 
                int defStyleRes)

Parameters
context Context

attrs AttributeSet

defStyleAttr int

defStyleRes int

Public methods

getAccessibilityClassName

Added in API level 23
public CharSequence getAccessibilityClassName ()

Return the class name of this object to be used for accessibility purposes. Subclasses should only override this if they are implementing something that should be seen as a completely new class of view when used by accessibility, unrelated to the class it is deriving from. This is used to fill in AccessibilityNodeInfo.setClassName.

Returns
CharSequence

onResolvePointerIcon

Added in API level 24
public PointerIcon onResolvePointerIcon (MotionEvent event, 
                int pointerIndex)

Resolve the pointer icon that should be used for specified pointer in the motion event. The default implementation will resolve the pointer icon to one set using setPointerIcon(android.view.PointerIcon) for mouse devices. Subclasses may override this to customize the icon for the given pointer. For example, the pointer icon for a stylus pointer can be resolved in the following way:

 @Override
 public PointerIcon onResolvePointerIcon(MotionEvent event, int pointerIndex) {
     final int toolType = event.getToolType(pointerIndex);
     if (!event.isFromSource(InputDevice.SOURCE_MOUSE)
             && event.isFromSource(InputDevice.SOURCE_STYLUS)
             && (toolType == MotionEvent.TOOL_TYPE_STYLUS
                     || toolType == MotionEvent.TOOL_TYPE_ERASER)) {
         // Show this pointer icon only if this pointer is a stylus.
         return PointerIcon.getSystemIcon(mContext, PointerIcon.TYPE_WAIT);
     }
     // Use the default logic for determining the pointer icon for other non-stylus pointers,
     // like for the mouse cursor.
     return super.onResolvePointerIcon(event, pointerIndex);
 }
 

Parameters
event MotionEvent: The MotionEvent that requires a pointer icon to be resolved for one of pointers.

pointerIndex int: The index of the pointer in event for which to retrieve the PointerIcon. This will be between 0 and MotionEvent#getPointerCount().

Returns
PointerIcon the pointer icon to use for specified pointer, or null if a pointer icon is not specified and the default icon should be used.

Protected methods

onSetAlpha

Added in API level 1
protected boolean onSetAlpha (int alpha)

Invoked if there is a Transform that involves alpha. Subclass that can draw themselves with the specified alpha should return true, and then respect that alpha when their onDraw() is called. If this returns false then the view may be redirected to draw into an offscreen buffer to fulfill the request, which will look fine, but may be slower than if the subclass handles it internally. The default implementation returns false.

Parameters
alpha int: The alpha (0..255) to apply to the view's drawing

Returns
boolean true if the view can draw with the specified alpha.