按钮在Activity屏幕中拖动，定位

private ImageView img1;
	private int screenWidth;
	private int screenHeight;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		img1 = (ImageView) findViewById(R.id.imageView1);

		DisplayMetrics dm = getResources().getDisplayMetrics();
		screenWidth = dm.widthPixels;
		screenHeight = dm.heightPixels - 50;

		img1.setOnTouchListener(movingEventListener);
		img1.setOnClickListener(new OnClickListener() {
			
			public void onClick(View v) {
				System.out.println(333333);
				Toast.makeText(RemoveImageActivity.this, "点击咯", Toast.LENGTH_SHORT).show();
			}
		});
	}

	private OnTouchListener movingEventListener = new OnTouchListener() {
		int lastX, lastY;

		public boolean onTouch(View v, MotionEvent event) {
			if (event.getAction() == event.ACTION_DOWN) {
				lastX = (int) event.getRawX();
				lastY = (int) event.getRawY();
				System.out.println(11111);
			}
			if (event.getAction() == event.ACTION_MOVE) {
				System.out.println(222222);
				int dx = (int) event.getRawX() - lastX;
				int dy = (int) event.getRawY() - lastY;

				int left = v.getLeft() + dx;
				int top = v.getTop() + dy;
				int right = v.getRight() + dx;
				int bottom = v.getBottom() + dy;
				// 设置不能出界
				if (left < 0) {
					left = 0;
					right = left + v.getWidth();
				}

				if (right > screenWidth) {
					right = screenWidth;
					left = right - v.getWidth();
				}

				if (top < 0) {
					top = 0;
					bottom = top + v.getHeight();
				}

				if (bottom > screenHeight) {
					bottom = screenHeight;
					top = bottom - v.getHeight();
				}

				v.layout(left, top, right, bottom);

				lastX = (int) event.getRawX();
				lastY = (int) event.getRawY();

			}
			return true;
		}
	};

 

如何返回值為TRUE，那麼，如果按鈕还有点击事件的话，点击事件失效了（监听不到）；

如果返回值为FALSE。那么，拖动事件完毕之后，立即就执行了点击事件