android四种更新UI的方法

时间:2023-03-09 03:04:21
android四种更新UI的方法

笔记:

// 使用handler.post(Runnable)更新UI
public void updateUI_Fun1() {
new Thread() {
public void run() {
Handler handler = new Handler();
handler.post(new Runnable() { @Override
public void run() {
textView.setText("this is update content");
}
});
};
}.start();
} // 使用handler发送消息更新UI
public void updateUI_Fun2() {
Handler handler = new Handler(new Callback() { @Override
public boolean handleMessage(Message msg) {
// 对handler发送消息的预处理,返回falst则执行下面的handlerMessage() true则不执行 return false;
}
}) {
public void handleMessage(Message msg) {
textView.setText("this is update content");
};
};
} // 使用UI线程更新UI
public void updataUI_Fun3() {
runOnUiThread(new Runnable() { @Override
public void run() {
textView.setText("updata ui content");
}
});
} // 使用View.post( Runnable)更新UI
public void updateUI_Fun4() {
textView.post(new Runnable() { @Override
public void run() {
textView.setText("this is update context"); }
});
}

使用子线程自带的Looper更新UI:

代码笔记:

private Handler handler2;
private HandlerThread thread; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second); myHandlerThread = (Button) findViewById(R.id.MyThreadHandler);
handlerThread = (Button) findViewById(R.id.HandlerThread); //利用HandlerThread线程执行耗时操作,可以简单代替AsyncTask等。主线程给子线程发送消息
handlerThread.setOnClickListener(new OnClickListener() { @Override
public void onClick(View v) {
thread=new HandlerThread("aaaa");
thread.start();
handler2=new Handler(thread.getLooper()){
@Override
public void handleMessage(Message msg) {
Toast.makeText(SecondActivity.this, "this is HandlerThread", Toast.LENGTH_SHORT).show();
}
};
handler2.sendEmptyMessage(1);
}
});