Android开发更新UI的几种方式

1、runOnUiThread

2、handler post

3、handler sendmessage

4、view post

　xml布局文件：　　　　　　　　

　　<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
　　xmlns:tools="http://schemas.android.com/tools"
　　android:layout_width="match_parent"
　　android:layout_height="match_parent"
　　android:paddingBottom="@dimen/activity_vertical_margin"
　　android:paddingLeft="@dimen/activity_horizontal_margin"
　　android:paddingRight="@dimen/activity_horizontal_margin"
　　android:paddingTop="@dimen/activity_vertical_margin"
　　tools:context="com.example.handlerui.MainActivity" >

　　<TextView
　　android:id="@+id/textView"
　　android:layout_width="wrap_content"
　　android:layout_height="wrap_content"
　　android:textSize="50sp"
　　android:text="@string/hello_world" />

　　</RelativeLayout>

　　MainActivity.java

　　

package com.example.handlerui;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

public class MainActivity extends Activity {

	private TextView textView;

	private Handler handler = new Handler(){
		public void handleMessage(android.os.Message msg) {
			//textView.setText("OK");	//使用handler2更新UI的时候去掉注释

　　　　　　};

	};

	private void handler1(){
		handler.post(new Runnable() {

			@Override
			public void run() {
				// TODO Auto-generated method stub
				textView.setText("OK");
			}
		});
	}

	private void handler2(){
		handler.sendEmptyMessage(1);
	}

	private void updateUi(){
		runOnUiThread(new Runnable() {

			@Override
			public void run() {
				// TODO Auto-generated method stub
				textView.setText("OK");
			}
		});
	}

	private void viewUI(){
		textView.post(new Runnable() {

			@Override
			public void run() {
				// TODO Auto-generated method stub
				textView.setText("OK");
			}
		});
	}
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textView = (TextView) findViewById(R.id.textView);
        new Thread(){
        	public void run() {
        		try {
					Thread.sleep(2000);
					//handler1();
					handler2();
					//updateUi();
					//viewUI();
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}

        	};
        }.start();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}