Android消息处理学习笔记（一）

public boolean dispatchTouchEvent(MotionEvent ev)
public boolean onInterceptTouchEvent(MotionEvent ev)
public boolean onTouchEvent(MotionEvent event)

    /**
     * Constant for {@link #getActionMasked}: A pressed gesture has started, the
     * motion contains the initial starting location.
     * <p>
     * This is also a good time to check the button state to distinguish
     * secondary and tertiary button clicks and handle them appropriately.
     * Use {@link #getButtonState} to retrieve the button state.
     * </p>
     */
    public static final int ACTION_DOWN             = 0;

    /**
     * Constant for {@link #getActionMasked}: A pressed gesture has finished, the
     * motion contains the final release location as well as any intermediate
     * points since the last down or move event.
     */
    public static final int ACTION_UP               = 1;

    /**
     * Constant for {@link #getActionMasked}: A change has happened during a
     * press gesture (between {@link #ACTION_DOWN} and {@link #ACTION_UP}).
     * The motion contains the most recent point, as well as any intermediate
     * points since the last down or move event.
     */
    public static final int ACTION_MOVE             = 2;

    /**
     * Constant for {@link #getActionMasked}: The current gesture has been aborted.
     * You will not receive any more points in it.  You should treat this as
     * an up event, but not perform any action that you normally would.
     */
    public static final int ACTION_CANCEL           = 3;

return super.onTouchEvent(event);
return true;
return false;