安卓Handler的使用簡單例子
阿新 • • 發佈:2018-11-08
public class MainActivity extends AppCompatActivity { private TextView textView; private String TAG = "MainActivity"; private int i = 0; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView = (TextView) findViewById(R.id.textView); } public void onClick(View v){ ++i; //建立新的執行緒 new Thread(){ @Override public void run() { super.run(); doSendMsg(); } }.start(); } /* * 在子執行緒中做耗時操作,完成之後,通知Handler更新UI */ private void doSendMsg(){ try { Thread.sleep(1000);//模擬耗時操作 } catch (InterruptedException e) { e.printStackTrace(); } Message message = Message.obtain(); message.arg1 = i; message.what = 1; mHandler.sendMessage(message); } Handler mHandler = new Handler(){ /* * handleMessage接收訊息後進行相應的處理 */ @Override public void handleMessage(Message msg) { super.handleMessage(msg); if(msg.what==1){ textView.setText(msg.arg1+""); } } }; }