package com.lucky.test36asynctask;

import android.annotation.SuppressLint;

import android.app.ProgressDialog;

import android.content.Context;

import android.os.AsyncTask;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    Button button1;

    TextView textView;

    ProgressDialog progressDialog; //定义一个进度对话框

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        button1=findViewById(R.id.button);

        textView=findViewById(R.id.textview);

        button1.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                MyAsyncTask myAsyncTask=new MyAsyncTask(MainActivity.this);

                myAsyncTask.execute(new Integer(0));

            }

        });

    }

    @SuppressLint("StaticFieldLeak")

    private class MyAsyncTask extends AsyncTask<Integer,Integer,String>{

        public Context context1;

        //构造方法

        public MyAsyncTask(Context context){

            this.context1=context;

        }

        //在异步任务执行之前执行的操作

        @Override

        protected void onPreExecute() {

            progressDialog=new ProgressDialog(context1); //实例化进度对话框

            progressDialog.setIcon(R.mipmap.ic_launcher); //设置图标

            progressDialog.setTitle("提示");  //设置标题

            progressDialog.setMessage("任务正在进行"); //设置内容

            progressDialog.setMax(100); //设置进度条的最大值

            progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); //设置进度对话框的样式

            progressDialog.show(); //显示进度对话框

        }

        //执行耗时任务

        @Override

        protected String doInBackground(Integer... integers) {

            int i=integers[0];

            for (int j = i; j <100 ; j++) {

                publishProgress(j);  //发布进度值到更新任务

                try {

                    Thread.sleep(100); //延时0.1s

                } catch (InterruptedException e) {

                    e.printStackTrace();

                }

            }

            return "任务已经完成";

        }

        //任务结束后执行的任务

        @Override

        protected void onPostExecute(String s) {

            super.onPostExecute(s);

            progressDialog.dismiss();//关闭进度对话框

            textView.setText(s);    //注意：s来自于doInBackground执行完成后的return返回值

        }

        //更新任务

        @Override

        protected void onProgressUpdate(Integer... values) {

            super.onProgressUpdate(values);

            progressDialog.setProgress(values[0]); //接收doInBackground发布的进度值，更新进度值

        }

    }

}