Andriod【进度条加进度百分比的实现】（线程）

 

效果如图：

 

 

①：main页面布局

②

线程的注意事项：

      不能在主线程中执行耗时的操作，只能在子线程中操作
      另外，在子线程中不能操作主线程中的控件(ProgressBar除外)

 

public class MainActivity extends AppCompatActivity {
    private ProgressBar main_pro_pro1;//进度条
    private  int progress;
    private TextView main_tv_tv1;//进度条百分比
    private MyHandler myHandler = new MyHandler();
    private  int code = 1;//线程编号
    private class MyHandler extends Handler{
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            if(code == msg.what){
                progress++;
                main_pro_pro1.setProgress(progress);
                main_tv_tv1.setText(progress+"%");
            }
        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        main_pro_pro1 = this.findViewById(R.id.main_pro_pro1);
        main_tv_tv1=this.findViewById(R.id.main_tv_tv1);
    }

    public void setProgress(View view) {
        if(0 == progress){
            new MyThread().start();//触发子线程
        }

    }

    //耗时操作放在MyThread(子线程)
    private class MyThread extends Thread{
        @Override
        public void run() {
            super.run();
            while (true){
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                if(progress==100){
                    progress=0;
                    break;
                }
                Message msg = new Message();
                msg.what=1;
                myHandler.sendMessage(msg);//Handler

            }

        }
    }

}