大家都知道由于性能要求，android要求只能在UI线程中更新UI，要想在其他线程中更新UI，我大致总结了4种方式，欢迎补充纠正：

使用Handler消息传递机制;

使用AsyncTask异步任务;

使用runOnUiThread(action)方法;

使用Handler的post(Runnabel r)方法;

下面分别使用四种方式来更新一个TextView。

1.使用Handler消息传递机制

public class MainActivity extends Activity {    private TextView tv;    Handler handler = new Handler()    {        public void handleMessage(android.os.Message msg) {                          tv.setText("更新后的TextView");                    };    };    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv = (TextView) findViewById(R.id.tv);        new MyThread().start();    }    class MyThread extends Thread    {        @Override        public void run() {            //延迟两秒更新            try {                Thread.sleep(2000);            } catch (InterruptedException e) {                // TODO Auto-generated catch block                e.printStackTrace();            }            handler.sendEmptyMessage();        }    }}

2.使用AsyncTask异步任务

注：更新UI的操作只能在onPostExecute(String result)方法中。

public class MainActivity extends Activity {    private TextView tv;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv = (TextView) findViewById(R.id.tv);        new Yibu().execute();    }    class Yibu extends AsyncTask
     
          {        @Override        protected String doInBackground(String... params) {            try {                Thread.sleep(2000);            } catch (InterruptedException e) {                // TODO Auto-generated catch block                e.printStackTrace();            }            return null;        }        @Override        protected void onPostExecute(String result) {            // TODO Auto-generated method stub            tv.setText("更新后的TextView");        }    }}
     

3.使用runOnUiThread(action)方法

public class MainActivity extends Activity {    private TextView tv;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv = (TextView) findViewById(R.id.tv);        new MyThread().start();    }    class MyThread extends Thread    {        @Override        public void run() {            runOnUiThread(new Runnable() {                @Override                public void run() {                    // TODO Auto-generated method stub                        try {                            //延迟两秒更新                            Thread.sleep(2000);                        } catch (InterruptedException e) {                            e.printStackTrace();                        }                        tv.setText("更新后的TextView");                }            });        }    }}

4.使用Handler的post(Runnabel r)方法

public class MainActivity extends Activity {    private TextView tv;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv = (TextView) findViewById(R.id.tv);        Handler handler = new Handler();        handler.post(new Runnable(){            @Override            public void run() {                try {                    //延迟两秒更新                    Thread.sleep(2000);                } catch (InterruptedException e) {                    e.printStackTrace();                }                tv.setText("更新后的TextView");            }        });    }}