Android 更新下载apk 安装apk 打开apk

1、需要添加的权限

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

2、activity

package com.junbo.downloadapkaudoinstall;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

/**
 * 下载Apk 自动安装Apk
 * 
 * @author Administrator
 * 
 */
public class MainActivity extends Activity {
	private static final String URL_STRING = "http://gdown.baidu.com/data/wisegame/b7d7e4efd8199dea/tianyiyuedu_310.apk";
	private File file;
	private ProgressDialog dialog;
	private HttpURLConnection connection;
	private Button button;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		button = (Button) this.findViewById(R.id.button);
		button.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				showWaitDialog(); // 弹出下载dialog
				downFile(URL_STRING);// 开始下载APK
			}
		});

	}

	/**
	 * 
	 * 显示更新状态，进度条
	 */
	public void showWaitDialog() {
		dialog = new ProgressDialog(this);
		dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
		dialog.setMessage("正在下载更新，请稍候...");
		dialog.show();
	}

	private Handler handler = new Handler() {

		@Override
		public void handleMessage(Message msg) {
			super.handleMessage(msg);
			switch (msg.what) {
			case 1:
				installApk();// 安装apk
				break;
			case 2:
				openApk(MainActivity.this, URL_STRING); // 打开apk
				break;
			}
		}

	};

	// 接收到安装完成apk的广播
	BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {

		@Override
		public void onReceive(Context context, Intent intent) {
			System.out.println("接收到安装完成apk的广播");
			Message message = handler.obtainMessage();
			message.what = 2;
			handler.sendMessage(message);
		}
	};

	/**
	 * 后台在下面一个Apk 下载完成后返回下载好的文件
	 * 
	 * @param httpUrl
	 * @return
	 */
	private File downFile(final String httpUrl) {
		new Thread(new Runnable() {

			@Override
			public void run() {
				try {
					URL url = new URL(httpUrl);
					connection = (HttpURLConnection) url.openConnection();
					connection.setRequestMethod("GET");
					connection.setConnectTimeout(5000);
					FileOutputStream fileOutputStream = null;
					InputStream inputStream;
					if (connection.getResponseCode() == 200) {
						inputStream = connection.getInputStream();

						if (inputStream != null) {
							file = getFile(httpUrl);
							delFile(file.getAbsolutePath());
							fileOutputStream = new FileOutputStream(file);
							byte[] buffer = new byte[1024];
							int length = 0;
							int total = 0;
							dialog.setMax(connection.getContentLength());
							while ((length = inputStream.read(buffer)) != -1) {
								fileOutputStream.write(buffer, 0, length);
								total += length;
								dialog.setProgress(total);
							}
							fileOutputStream.close();
							fileOutputStream.flush();
							dialog.cancel();
							dialog.dismiss();
						}
						inputStream.close();
					}

					System.out.println("已经下载完成");
					// 往handler发送一条消息 更改button的text属性
					Message message = handler.obtainMessage();
					message.what = 1;
					handler.sendMessage(message);
				} catch (MalformedURLException e) {
					e.printStackTrace();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}).start();
		return file;
	}

	/***
	 * 删除临时存放的文件
	 * 
	 * @param url
	 *            文件路径
	 */
	public void delFile(String url) {
		File myFile = new File(url);
		if (myFile.exists()) {
			myFile.delete();
		}
	}

	/**
	 * 安装APK
	 */
	private void installApk() {
		Intent intent = new Intent(Intent.ACTION_VIEW);
		intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");
		startActivity(intent);
	}

	@Override
	protected void onStart() {
		super.onStart();
		IntentFilter intentFilter = new IntentFilter();
		intentFilter.addAction(Intent.ACTION_PACKAGE_ADDED);
		intentFilter.addDataScheme("package");
		// 注册一个广播
		registerReceiver(broadcastReceiver, intentFilter);
	}

	@Override
	protected void onDestroy() {
		super.onDestroy();
		// 解除广播
		unregisterReceiver(broadcastReceiver);
	}

	/**
	 * 打开已经安装好的apk
	 */
	private void openApk(Context context, String url) {
		PackageManager manager = context.getPackageManager();
		// 这里的是你下载好的文件路径
		PackageInfo info = manager.getPackageArchiveInfo(Environment.getExternalStorageDirectory().getAbsolutePath() + getFilePath(url),
				PackageManager.GET_ACTIVITIES);
		if (info != null) {
			Intent intent = manager.getLaunchIntentForPackage(info.applicationInfo.packageName);
			startActivity(intent);
		}
	}

	/**
	 * 根据传过来url创建文件
	 * 
	 */
	private File getFile(String url) {
		File files = new File(Environment.getExternalStorageDirectory().getAbsoluteFile(), getFilePath(url));
		return files;
	}

	/**
	 * 截取出url后面的apk的文件名
	 * 
	 * @param url
	 * @return
	 */
	private String getFilePath(String url) {
		return url.substring(url.lastIndexOf("/"), url.length());
	}
}

3、 下载地址