Android 更新UI的方法匯總_Android

1、Activity的 runOnUiThread

textView = (TextView) findViewById( R.id.tv );new Thread(new Runnable() {@Overridepublic void run() {runOnUiThread(new Runnable() {@Overridepublic void run() {textView.setText( "更新UI了");}});}}).start();

android Activity runOnUiThread() 方法使用

2、Handler sendEmptyMessage()

package lib.com.myapplication;import android.os.Handler;import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.widget.TextView;public class MainActivity extends AppCompatActivity {private TextView textView ;Handler handler = new Handler( ) {@Overridepublic void handleMessage(Message msg) {super.handleMessage(msg);textView.setText( "Ui更新了");}};@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);textView = (TextView) findViewById( R.id.tv );new Thread(new Runnable() {@Overridepublic void run() {try {Thread.sleep( 2000 );} catch (InterruptedException e) {e.printStackTrace();}handler.sendEmptyMessage( 2 ) ;}}).start();}}

3、Handler post()

package lib.com.myapplication;import android.os.Bundle;import android.os.Handler;import android.support.v7.app.AppCompatActivity;import android.widget.TextView;public class MainActivity extends AppCompatActivity {private TextView textView ;Handler handler = new Handler();@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);textView = (TextView) findViewById( R.id.tv );new Thread(new Runnable() {@Overridepublic void run() {try {Thread.sleep( 2000 );} catch (InterruptedException e) {e.printStackTrace();}handler.post(new Runnable() {@Overridepublic void run() {textView.setText( "Ui更新了");}}) ;}}).start();}}

4、view Post()　

textView = (TextView) findViewById( R.id.tv );new Thread(new Runnable() {@Overridepublic void run() {try {Thread.sleep( 2000 );} catch (InterruptedException e) {e.printStackTrace();}textView.post(new Runnable() {@Overridepublic void run() {textView.setText( "Ui更新了");}}) ;}}).start();

總結：

1、其實上面的四種方式都可歸結於一種方式：handler 用於Android線程之間的通訊。

2、為什麼android要求只能在UI線程進行UI操作？ 主要還是為了避免多線程造成的並發的問題。在單線程操作UI是安全的。

以上所述是 給大家介紹的Android 更新UI的方法匯總的相關知識，希望對大家有所協助，如果大家有疑問歡迎給我留言，小編會及時回複大家的！