我更新进度条与MainActivity 的处理器的帮助,但它给人的错误:()内螺纹已不叫Looper.prepare无法创建处理程序它说,looper.prepare必须调用
public class MainActivity extends AppCompatActivity {
ProgressBar progressBar;
Handler handler;
Thread thread;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
progressBar = (ProgressBar) findViewById(R.id.progressBar);
thread = new Thread(new MyThread());
thread.start();
handler = new Handler() {
@Override
public void handleMessage(Message msg) {
progressBar.setProgress(msg.arg1);
}
};
}
class MyThread implements Runnable {
@Override
public void run() {
Message message = Message.obtain();
for (int i = 0; i < 100; i++) {
message.arg1 = i;
handler.sendMessage(message);
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
你的后台线程没有尺蠖,所以它不能调用Message.obtain() – EpicPandaForce