android - 拖动图像？

Question

我正在尝试做一些当用户将图像移动到某个地方时必须解锁的应用程序......但问题是当用户触摸除图像以外的其他地方时，它仍然试图移动并且它给出了这个错误: java.lang.ClassCastException: 安卓.widget.AbsoluteLayout$LayoutParams

这是我的代码:

公共(public)类主要扩展 Activity {

private View selected_item;
private int offset_x = 0;
private int offset_y = 0;

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

    final ViewGroup vg = (ViewGroup) findViewById(R.id.lout);

    vg.setOnTouchListener(new View.OnTouchListener() {

        @SuppressWarnings("deprecation")
        public boolean onTouch(View v, MotionEvent event) {
                      switch (event.getAction()) {                          
                      case MotionEvent.ACTION_MOVE:
                          int x = (int) event.getX() - offset_x;
                          int y = (int) event.getY() - offset_y;
                          Log.e("SONUC", "SONUC1: " + x + ", " + y);
                          int w = getWindowManager().getDefaultDisplay().getWidth() - 25;
                          int h = getWindowManager().getDefaultDisplay().getHeight() - 25;
                          if (x > w)
                              x = w;
                          if (y > h)
                              y = h;
                          Log.e("SONUC", "SONUC2: " + x + ", " + y);
                          AbsoluteLayout.LayoutParams lp = new AbsoluteLayout.LayoutParams(
                                  new ViewGroup.MarginLayoutParams(
                                          AbsoluteLayout.LayoutParams.WRAP_CONTENT,
                                          AbsoluteLayout.LayoutParams.WRAP_CONTENT));                              
                          lp.x = x;
                          lp.y = y;
                          Log.e("SONUC", "SONUC3: " + lp);
                          selected_item.setLayoutParams(lp);       

                          break;

                      case MotionEvent.ACTION_UP:
                          offset_x = (int) event.getX() - offset_x;
                          offset_y = (int) event.getY() - offset_y;
                          Log.e("SONUC", "SONUC5: " + offset_x + ", " + offset_y);
                          selected_item = v;
                          if (offset_x < 220 && offset_x > 150 && offset_y < 330 && offset_y > 300)
                              startActivity(new Intent("com.yahya.GeneralTraining.UNLOCKED"));
                          break;

            default:
                break;
            }
            return true;
        }
    });

    ImageView img = (ImageView) findViewById(R.id.imageView1);
    img.setOnTouchListener(new View.OnTouchListener() {

        public boolean onTouch(View v, MotionEvent event) {
            switch (event.getAction()) {

            case MotionEvent.ACTION_DOWN:
                offset_x = (int) event.getX();
                offset_y = (int) event.getY();
                Log.e("SONUC", "SONUC4: " + offset_x + ", " + offset_y);                    
                selected_item = v;
                break;


            default:
                break;
            }
            return false;

        }
    });

}

Answer 1

您可以在 onTouchListener 中为 View 组提供一个检查，以确认图像最初被点击。

vg.setOnTouchListener(new View.OnTouchListener() {

    @SuppressWarnings("deprecation")
    public boolean onTouch(View v, MotionEvent event) {
                if(selected_item.getId() == R.id.image){
                    switch (event.getActionMasked()) {
                      //your code
                    }
                }
        }
        return true;
    }
});