StackView


public class StackView
extends AdapterViewAnimator

java.lang.Object
   ↳ android.view.View
     ↳ android.view.ViewGroup
       ↳ android.widget.AdapterView<android.widget.Adapter>
         ↳ android.widget.AdapterViewAnimator
           ↳ android.widget.StackView


Summary

Inherited XML attributes

Inherited constants

Inherited fields

Public constructors

StackView(Context context)

StackView(Context context, AttributeSet attrs)

StackView(Context context, AttributeSet attrs, int defStyleAttr)

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

Public methods

void advance()

Called by an AppWidgetHost in order to advance the current view when it is being used within an app widget.

CharSequence getAccessibilityClassName()

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

boolean onGenericMotionEvent(MotionEvent event)

Implement this method to handle generic motion events.

boolean onInterceptTouchEvent(MotionEvent ev)

Implement this method to intercept all touch screen motion events.

boolean onTouchEvent(MotionEvent ev)

Implement this method to handle touch screen motion events.

void showNext()

Manually shows the next child.

void showPrevious()

Manually shows the previous child.

Protected methods

void dispatchDraw(Canvas canvas)

Called by draw to draw the child views.

void onLayout(boolean changed, int left, int top, int right, int bottom)

Called from layout when this view should assign a size and position to each of its children.

void onMeasure(int widthMeasureSpec, int heightMeasureSpec)

Measure the view and its content to determine the measured width and the measured height.

Inherited methods

Public constructors

StackView

Added in API level 11
public StackView (Context context)

Parameters
context Context

StackView

Added in API level 11
public StackView (Context context, 
                AttributeSet attrs)

Parameters
context Context

attrs AttributeSet

StackView

Added in API level 14
public StackView (Context context, 
                AttributeSet attrs, 
                int defStyleAttr)

Parameters
context Context

attrs AttributeSet

defStyleAttr int

StackView

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

Parameters
context Context

attrs AttributeSet

defStyleAttr int

defStyleRes int

Public methods

advance

Added in API level 11
public void advance ()

Called by an AppWidgetHost in order to advance the current view when it is being used within an app widget.

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

onGenericMotionEvent

Added in API level 12
public boolean onGenericMotionEvent (MotionEvent event)

Implement this method to handle generic motion events.

Generic motion events describe joystick movements, hover events from mouse or stylus devices, trackpad touches, scroll wheel movements and other motion events not handled by onTouchEvent(android.view.MotionEvent) or onTrackballEvent(android.view.MotionEvent). The source of the motion event specifies the class of input that was received. Implementations of this method must examine the bits in the source before processing the event. The following code example shows how this is done.

Generic motion events with source class InputDevice#SOURCE_CLASS_POINTER are delivered to the view under the pointer. All other generic motion events are delivered to the focused view.

 public boolean onGenericMotionEvent(MotionEvent event) {
     if (event.isFromSource(InputDevice.SOURCE_CLASS_JOYSTICK)) {
         if (event.getAction() == MotionEvent.ACTION_MOVE) {
             // process the joystick movement...
             return true;
         }
     }
     if (event.isFromSource(InputDevice.SOURCE_CLASS_POINTER)) {
         switch (event.getAction()) {
             case MotionEvent.ACTION_HOVER_MOVE:
                 // process the hover movement...
                 return true;
             case MotionEvent.ACTION_SCROLL:
                 // process the scroll wheel movement...
                 return true;
         }
     }
     return super.onGenericMotionEvent(event);
 }

Parameters
event MotionEvent: The generic motion event being processed.

Returns
boolean True if the event was handled, false otherwise.

onInterceptTouchEvent

Added in API level 11
public boolean onInterceptTouchEvent (MotionEvent ev)

Implement this method to intercept all touch screen motion events. This allows you to watch events as they are dispatched to your children, and take ownership of the current gesture at any point.

Using this function takes some care, as it has a fairly complicated interaction with View.onTouchEvent(MotionEvent), and using it requires implementing that method as well as this one in the correct way. Events will be received in the following order:

  1. You will receive the down event here.
  2. The down event will be handled either by a child of this view group, or given to your own onTouchEvent() method to handle; this means you should implement onTouchEvent() to return true, so you will continue to see the rest of the gesture (instead of looking for a parent view to handle it). Also, by returning true from onTouchEvent(), you will not receive any following events in onInterceptTouchEvent() and all touch processing must happen in onTouchEvent() like normal.
  3. For as long as you return false from this function, each following event (up to and including the final up) will be delivered first here and then to the target's onTouchEvent().
  4. If you return true from here, you will not receive any following events: the target view will receive the same event but with the action MotionEvent#ACTION_CANCEL, and all further events will be delivered to your onTouchEvent() method and no longer appear here.

Parameters
ev MotionEvent: The motion event being dispatched down the hierarchy.

Returns
boolean Return true to steal motion events from the children and have them dispatched to this ViewGroup through onTouchEvent(). The current target will receive an ACTION_CANCEL event, and no further messages will be delivered here.

onTouchEvent

Added in API level 11
public boolean onTouchEvent (MotionEvent ev)

Implement this method to handle touch screen motion events.

If this method is used to detect click actions, it is recommended that the actions be performed by implementing and calling performClick(). This will ensure consistent system behavior, including:

  • obeying click sound preferences
  • dispatching OnClickListener calls
  • handling ACTION_CLICK when accessibility features are enabled

Parameters
ev MotionEvent: The motion event.

Returns
boolean True if the event was handled, false otherwise.

showNext

Added in API level 11
public void showNext ()

Manually shows the next child.

showPrevious

Added in API level 11
public void showPrevious ()

Manually shows the previous child.

Protected methods

dispatchDraw

Added in API level 11
protected void dispatchDraw (Canvas canvas)

Called by draw to draw the child views. This may be overridden by derived classes to gain control just before its children are drawn (but after its own view has been drawn).

Parameters
canvas Canvas: This value cannot be null.

onLayout

Added in API level 11
protected void onLayout (boolean changed, 
                int left, 
                int top, 
                int right, 
                int bottom)

Called from layout when this view should assign a size and position to each of its children. Derived classes with children should override this method and call layout on each of their children.

Parameters
changed boolean: This is a new size or position for this view

left int: Left position, relative to parent

top int: Top position, relative to parent

right int: Right position, relative to parent

bottom int: Bottom position, relative to parent

onMeasure

Added in API level 11
protected void onMeasure (int widthMeasureSpec, 
                int heightMeasureSpec)

Measure the view and its content to determine the measured width and the measured height. This method is invoked by measure(int, int) and should be overridden by subclasses to provide accurate and efficient measurement of their contents.

CONTRACT: When overriding this method, you must call setMeasuredDimension(int, int) to store the measured width and height of this view. Failure to do so will trigger an IllegalStateException, thrown by measure(int, int). Calling the superclass' onMeasure(int, int) is a valid use.

The base class implementation of measure defaults to the background size, unless a larger size is allowed by the MeasureSpec. Subclasses should override onMeasure(int, int) to provide better measurements of their content.

If this method is overridden, it is the subclass's responsibility to make sure the measured height and width are at least the view's minimum height and width (getSuggestedMinimumHeight() and getSuggestedMinimumWidth()).

Parameters
widthMeasureSpec int: horizontal space requirements as imposed by the parent. The requirements are encoded with View.MeasureSpec.

heightMeasureSpec int: vertical space requirements as imposed by the parent. The requirements are encoded with View.MeasureSpec.