Android基于widget组件实现物体移动/控件拖动功能示例

package com.sky;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AbsoluteLayout;
import android.widget.Button;
@SuppressWarnings("deprecation")
public class AbosoluteMove extends Activity implements OnClickListener
{
 /** Called when the activity is first created. */
 public Button button1;
 public Button button2;
 public Button button3;
 public Button button4;
 Button tmp;//临时保存，选择的BUTTON
 int x;
 int y;
 int flag;//用于标志选择哪个BUTTON
  @Override
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    button1=(Button) findViewById(R.id.widget27);
    button2=(Button) findViewById(R.id.widget28);
    button3=(Button) findViewById(R.id.widget29);
    button4=(Button) findViewById(R.id.widget30);
    button1.setOnClickListener(this);
    button2.setOnClickListener(this);
    button3.setOnClickListener(this);
    button4.setOnClickListener(this);
  }
 @Override
 public void onClick(View v)
 {
 // TODO Auto-generated method stub
 switch(v.getId())
 {
  case R.id.widget27:
  flag=R.id.widget27;
  setTitle("button1");
  break;
  case R.id.widget28:
  flag=R.id.widget28;
  setTitle("button2");
  break;
  case R.id.widget29:
  flag=R.id.widget29;
  setTitle("button3");
  break;
  case R.id.widget30:
  flag=R.id.widget30;
  setTitle("button4");
  break;
 }
 }
 @Override
 public boolean onKeyDown(int keyCode, KeyEvent event)
 {
 // TODO Auto-generated method stub
 return super.onKeyDown(keyCode, event);
 }
 @Override
 public boolean onTouchEvent(MotionEvent event)
 {
 // TODO Auto-generated method stub
 x = (int) event.getX();
    y = (int) event.getY();
    tmp=(Button) findViewById(flag);//获取所选中的BUTTON
    AbsoluteLayout.LayoutParams params1=new AbsoluteLayout.LayoutParams(50,50,x-25,y-50);
    tmp.setLayoutParams(params1);//设置BUTTON的新位置
    switch(event.getAction())
    {
      case MotionEvent.ACTION_DOWN:
       tmp.invalidate();
       tmp.setText("选中down");
        break;
      case MotionEvent.ACTION_UP:
       tmp.invalidate();
       tmp.setText("选中UP");
        break;
      case MotionEvent.ACTION_MOVE:
       tmp.invalidate();
       tmp.setText("选中move");
        break;
    }
    return super.onTouchEvent(event);
 }
}