Android攻城狮 multi-touch多点触摸

//多点触摸的简单应用----拖动图片
public class MainActivity extends Activity {
    private FrameLayout root;
    private ImageView imageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        imageView = (ImageView) findViewById(R.id.image);
        root = (FrameLayout) findViewById(R.id.container);
        // 监听触摸事件
        root.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                // TODO Auto-generated method stub
                switch (event.getAction()) {
                // 触摸按下
                case MotionEvent.ACTION_DOWN:
                    System.out.println("----->>ACTION_DOWN");
                    break;
                // 触摸移动
                case MotionEvent.ACTION_MOVE:
                    System.out.println("----->>ACTION_MOVE");
                    // 获取一个触摸点
                    System.out.println(String.format("x:%f,y:%f", event.getX(),
                            event.getY()));
                    // ---------获取一个安卓Android触摸点坐标-----拖动图片----------------
                    FrameLayout.LayoutParams lp = (LayoutParams) imageView
                            .getLayoutParams();
                    lp.leftMargin = (int) event.getX();
                    lp.topMargin = (int) event.getY();
                    imageView.setLayoutParams(lp);

                    System.out.println("===>>触摸点个数" + event.getPointerCount());
                    // 获取多个触摸点----只能在真机上测试
                    // System.out.println(String.format("x1:%f y1:%f,x2:%f, y2:%f",
                    // event.getX(0),event.getY(0),event.getX(1),event.getY(2)));
                    break;
                // 触摸抬起
                case MotionEvent.ACTION_UP:
                    System.out.println("----->>ACTION_UP");
                    break;

                default:
                    break;
                }
                return true;// 后续事件是否需要被触发
            }
        });
    }

}

//多点触摸的简单应用----实现图片的放大缩小
public class MainActivity extends Activity {
    private FrameLayout root;
    private ImageView imageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        imageView = (ImageView) findViewById(R.id.image);
        root = (FrameLayout) findViewById(R.id.container);
        // 监听触摸事件
        root.setOnTouchListener(new OnTouchListener() {
            float currentDistance;
            float lastDistance = -1;

            @Override
            public boolean onTouch(View v, MotionEvent event) {

                // TODO Auto-generated method stub
                switch (event.getAction()) {
                // 触摸按下
                case MotionEvent.ACTION_DOWN:
                    System.out.println("----->>ACTION_DOWN");
                    break;
                // 触摸移动
                case MotionEvent.ACTION_MOVE:
                    if (event.getPointerCount() >= 2) {
                        // 计算两点之间的距离
                        float offsetX = event.getX(0) - event.getX(1);
                        float offsetY = event.getY(0) - event.getY(1);
                        currentDistance = (float) Math.sqrt(offsetX * offsetX
                                + offsetY * offsetY);
                    }
                    if (lastDistance < 0) {// 初始化
                        lastDistance = currentDistance;
                    } else {
                        if (currentDistance - lastDistance > 5) {
                            System.out.println("放大");
                            FrameLayout.LayoutParams lp = (LayoutParams) imageView
                                    .getLayoutParams();
                            lp.width = (int) (imageView.getWidth() * 1.1);
                            lp.height = (int) (imageView.getHeight() * 1.1);
                            imageView.setLayoutParams(lp);
                            lastDistance = currentDistance;

                        } else if (currentDistance - lastDistance < 5) {
                            System.out.println("缩小");
                            FrameLayout.LayoutParams lp = (LayoutParams) imageView
                                    .getLayoutParams();
                            lp.width = (int) (imageView.getWidth() * 0.9);
                            lp.height = (int) (imageView.getHeight() * 0.9);
                            imageView.setLayoutParams(lp);
                            lastDistance = currentDistance;
                        }
                    }
                    System.out.println("----->>ACTION_MOVE");
                    // 获取一个触摸点
                    System.out.println(String.format("x:%f,y:%f", event.getX(),
                            event.getY()));

                    System.out.println("===>>触摸点个数" + event.getPointerCount());
                    // 获取多个触摸点----只能在真机上测试
                    // System.out.println(String.format("x1:%f y1:%f,x2:%f, y2:%f",
                    // event.getX(0),event.getY(0),event.getX(1),event.getY(2)));
                    break;
                // 触摸抬起
                case MotionEvent.ACTION_UP:
                    System.out.println("----->>ACTION_UP");
                    break;

                default:
                    break;
                }
                return true;// 后续事件是否需要被触发
            }
        });
    }

}