Async异步处理

MyAsync

package com.zhangmeng.xml;

import android.os.AsyncTask;
import android.widget.ProgressBar;
import android.widget.TextView;

/**
 * Created by zhangmeng on 2016/10/6.
 */

public class MyAsync extends AsyncTask<Integer,Integer,String> {
     private ProgressBar bar;
     private TextView tv;

    public MyAsync(ProgressBar bar,TextView tv) {
        super();
        this.bar = bar;
        this.tv=tv;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        tv.setText("The file is downloading! Please wait....");
    }





    @Override
    protected String doInBackground(Integer... params) {
        DelayOperator delayOperator=new DelayOperator();
        int i;
        for (i = 1; i <1000000; i++) {
            delayOperator.delay(params[0]);
            publishProgress(i);
        }

        return i + params[0].intValue() + "";
    }


    @Override
    protected void onProgressUpdate(Integer... values) {
        bar.setProgress(values[0]);

    }
}

package com.zhangmeng.xml;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    private Button bt;
    private TextView textView;
    private ProgressBar bar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        bt= (Button) findViewById(R.id.btn);
        textView=(TextView) findViewById(R.id.tv);
        bar=(ProgressBar) findViewById(R.id.pb);
        bt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                MyAsync async=new MyAsync(bar,textView);
                async.execute(100);
            }
        });



    }



}

delay

package com.zhangmeng.xml;

/**
 * Created by zhangmeng on 2016/10/5.
 */

public class DelayOperator {
    public void delay(int time){
        try {
            Thread.sleep(time);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}