Android得到控件在屏幕中的坐标

getLocationOnScreen ，计算该视图在全局坐标系中的x，y值，（注意这个值是要从屏幕顶端算起，也就是索包括了通知栏的高度）//获取在当前屏幕内的绝对坐标 
getLocationInWindow ，计算该视图在它所在的widnow的坐标x，y值，//获取在整个窗口内的绝对坐标 (不是很理解= =、)
getLeft , getTop, getBottom, getRight, 这一组是获取相对在它父亲里的坐标
如果在Activity的OnCreate()事件输出那些参数，是全为0，要等UI控件都加载完了才能获取到这些。

package xiaosi.location;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class LocationActivity extends Activity {
    /** Called when the activity is first created. */
    private ImageView t = null;
    private Button button = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        t = (ImageView)findViewById(R.id.l);
        button = (Button)findViewById(R.id.button);
        button.setOnClickListener(new buttonListener());
    }   
    public class buttonListener implements OnClickListener{

        public void onClick(View v)
        {
            int[] location = new int[2];
            t.getLocationOnScreen(location);
            int x = location[0];
            int y = location[1];
            System.out.println("x:"+x+"y:"+y);
            System.out.println("图片各个角Left："+t.getLeft()+"Right："+t.getRight()+"Top："+t.getTop()+"Bottom："+t.getBottom());
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/button"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="button"/>
    <ImageView
        android:id="@+id/l"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:src="@drawable/a" />
</LinearLayout>