1、设置权限

2、业务代码

package com.example.esri.app04.network;

import android.app.ProgressDialog;

import android.content.Intent;

import android.net.Uri;

import android.os.SystemClock;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.view.View;

import java.io.File;

import java.io.FileOutputStream;

import java.io.InputStream;

import java.net.HttpURLConnection;

import java.net.URI;

import java.net.URL;

public class MainActivity extends AppCompatActivity {

private File apkFile;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

}

public void downloadAPK(View v){

final ProgressDialog dialog = new ProgressDialog(this);

dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);

dialog.show();

//准备用于保存apk文件的file对象 放在sd卡里面

apkFile = new File(getExternalFilesDir(null), "update.apk");

//启动分线程下载数据，显示下载进度

new Thread(new Runnable() {

@Override

public void run() {

try{

//1 得到链接对象

String path = "http://192.168.0.184:8080/storage.apk";

URL url = new URL(path);

HttpURLConnection connection = (HttpURLConnection) url.openConnection();

connection.setConnectTimeout(5000);

connection.setReadTimeout(10000);

connection.connect();

int responseCode = connection.getResponseCode();

if(responseCode == 200){

//设置dialog最大进度

dialog.setMax(connection.getContentLength());

InputStream is = connection.getInputStream();

FileOutputStream fos = new FileOutputStream(apkFile);

byte[] buffer = new byte[1024];

int len = -1;

while ((len = is.read(buffer)) != -1){

fos.write(buffer, 0, len);

dialog.incrementProgressBy(len);

}

fos.close();

is.close();

}

connection.disconnect();

//主线程，移除dialog，启动安装

runOnUiThread(new Runnable() {

@Override

public void run() {

dialog.dismiss();

installAPK();

}

});

}catch (Exception e){

e.printStackTrace();

}

}

}).start();

}

/**

* 启动安装apk

*/

private void installAPK() {

Intent intent = new Intent("android.intent.action.INSTALL_PACKAGE");

intent.setDataAndType(Uri.fromFile(apkFile), "application/vnd.android.package-archive");

startActivity(intent);

}

}