深刻理解getLocationInWindow 和 getLocationOnScreen区别

       

概念

 getLocationInWindow是以B为原点的C的坐标

 getLocationOnScreen是以A为原点的C的坐标

没有弹出窗口位置效果截图：

  

弹出窗口后位置效果截图：

总结：所以以上2种方法得到绝对位置的方法只在有弹出窗时会有区别。

可参考源码：

package com.example.zdemo_getlocation;

import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.os.Handler;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.RelativeLayout;
import android.widget.TextView;

public class MainActivity extends Activity
{
	TextView _tv;
	@Override
	protected void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		_tv= (TextView) findViewById(R.id.tv);
		_tv.postDelayed(new Runnable()
		{

			@Override
			public void run()
			{
				// TODO Auto-generated method stub
				StringBuilder  sb=new StringBuilder();
				
				sb.append("父控件相对于它的父控件左上角位置:");
				sb.append(((ViewGroup)_tv.getParent()).getLeft()+","+((ViewGroup)_tv.getParent()).getTop()+"\n");
				sb.append("\n当前控件在相对父控件左上角位置:" + _tv.getLeft() + "," + _tv.getTop()+"\n");
				int[] loc1=new int[2];
				int[] loc2=new int[2];
				_tv.getLocationInWindow(loc1);
				_tv.getLocationOnScreen(loc2);
				sb.append("\n当前控件相对于窗口左上角位置");
				sb.append("\ngetLocationInWindow"+"("+loc1[0]+","+loc1[1]+")\n");
				sb.append("\n当前控件相对于屏幕左上角位置");
				sb.append("\ngetLocationOnScreen"+"("+loc2[0]+","+loc2[1]+")\n");
				
				
				
				
			
				
				_tv.setText(sb.toString());
			}
		}, 2000);
		
		findViewById(R.id.btn).setOnClickListener(new OnClickListener()
		{
			
			@Override
			public void onClick(View v)
			{
				// TODO Auto-generated method stub
				AlertDialog.Builder  builder=new AlertDialog.Builder(MainActivity.this);
				final TextView tv=new TextView(MainActivity.this);
			    builder.setView(tv);
			    builder.create().show();
				tv.postDelayed(new Runnable()
				{
					
					@Override
					public void run()
					{
						// TODO Auto-generated method stub
						StringBuilder  SB=new StringBuilder();
						int[] loc1=new int[2];
						int[] loc2=new int[2];
						tv.getLocationInWindow(loc1);
						tv.getLocationOnScreen(loc2);
						SB.append("当前控件相对于窗口左上角位置");
						SB.append("\ngetLocationInWindow"+"("+loc1[0]+","+loc1[1]+")\n");
						SB.append("\n当前控件相对于屏幕左上角位置");
						SB.append("\ngetLocationOnScreen"+"("+loc2[0]+","+loc2[1]+")\n");
						tv.setText(SB.toString());
					}
				}, 1000);
			}
		});
	
	}

}

资源文件activity_main.xml