Android 软件自动更新功能的实现

不念不忘少年蓝@ 2022-06-13 01:51 243阅读 0赞

原文地址：[http://blog.csdn.net/android\_tutor/article/details/7015986][http_blog.csdn.net_android_tutor_article_details_7015986]

一个好的应用软件都是需要好的维护，从初出版本到最后精品，这个过程需要版本不停的更新，那么如何让用户第一时间获取最新的应用安装包呢？那么就要求我们从第一个版本就要实现升级模块这一功能。

自 动更新功能的实现原理，就是我们事先和后台协商好一个接口，我们在应用的主Activity里，去访问这个接口，如果需要更新，后台会返回一些数据(比 如，提示语；最新版本的url等)。然后我们给出提示框，用户点击开始下载，下载完成开始覆盖安装程序，这样用户的应用就保持最新的拉。

为了让大家容易理解，我像往常一样准备一个小例子，这里为了方便我就省去了和后台交互部分了。步骤分别如下：

第一步：新建一个Android工程命名为:UpdateDemo.代码结构如下图所示：

![0_13319037812g3k.gif][]

第二步：新建一个UpdateManager.java类，负责软件更新功能模块，代码如下：

package com.tutor.update;
    
    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.AlertDialog;
    import android.app.Dialog;
    import android.app.AlertDialog.Builder;
    import android.content.Context;
    import android.content.DialogInterface;
    import android.content.Intent;
    import android.content.DialogInterface.OnClickListener;
    import android.net.Uri;
    import android.os.Handler;
    import android.os.Message;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.widget.ProgressBar;
    
    public class UpdateManager {
    
    	private Context mContext;
    	
    	//提示语
    	private String updateMsg = "有最新的软件包哦，亲快下载吧~";
    	
    	//返回的安装包url
    	private String apkUrl = "http://softfile.3g.qq.com:8080/msoft/179/24659/43549/qq_hd_mini_1.4.apk";
    	
    	
    	private Dialog noticeDialog;
    	
    	private Dialog downloadDialog;
    	 /* 下载包安装路径 */
        private static final String savePath = "/sdcard/updatedemo/";
        
        private static final String saveFileName = savePath + "UpdateDemoRelease.apk";
    
        /* 进度条与通知ui刷新的handler和msg常量 */
        private ProgressBar mProgress;
    
        
        private static final int DOWN_UPDATE = 1;
        
        private static final int DOWN_OVER = 2;
        
        private int progress;
        
        private Thread downLoadThread;
        
        private boolean interceptFlag = false;
        
        private Handler mHandler = new Handler(){
        	public void handleMessage(Message msg) {
        		switch (msg.what) {
    			case DOWN_UPDATE:
    				mProgress.setProgress(progress);
    				break;
    			case DOWN_OVER:
    				
    				installApk();
    				break;
    			default:
    				break;
    			}
        	};
        };
        
    	public UpdateManager(Context context) {
    		this.mContext = context;
    	}
    	
    	//外部接口让主Activity调用
    	public void checkUpdateInfo(){
    		showNoticeDialog();
    	}
    	
    	
    	private void showNoticeDialog(){
    		AlertDialog.Builder builder = new Builder(mContext);
    		builder.setTitle("软件版本更新");
    		builder.setMessage(updateMsg);
    		builder.setPositiveButton("下载", new OnClickListener() {			
    			@Override
    			public void onClick(DialogInterface dialog, int which) {
    				dialog.dismiss();
    				showDownloadDialog();			
    			}
    		});
    		builder.setNegativeButton("以后再说", new OnClickListener() {			
    			@Override
    			public void onClick(DialogInterface dialog, int which) {
    				dialog.dismiss();				
    			}
    		});
    		noticeDialog = builder.create();
    		noticeDialog.show();
    	}
    	
    	private void showDownloadDialog(){
    		AlertDialog.Builder builder = new Builder(mContext);
    		builder.setTitle("软件版本更新");
    		
    		final LayoutInflater inflater = LayoutInflater.from(mContext);
    		View v = inflater.inflate(R.layout.progress, null);
    		mProgress = (ProgressBar)v.findViewById(R.id.progress);
    		
    		builder.setView(v);
    		builder.setNegativeButton("取消", new OnClickListener() {	
    			@Override
    			public void onClick(DialogInterface dialog, int which) {
    				dialog.dismiss();
    				interceptFlag = true;
    			}
    		});
    		downloadDialog = builder.create();
    		downloadDialog.show();
    		
    		downloadApk();
    	}
    	
    	private Runnable mdownApkRunnable = new Runnable() {	
    		@Override
    		public void run() {
    			try {
    				URL url = new URL(apkUrl);
    			
    				HttpURLConnection conn = (HttpURLConnection)url.openConnection();
    				conn.connect();
    				int length = conn.getContentLength();
    				InputStream is = conn.getInputStream();
    				
    				File file = new File(savePath);
    				if(!file.exists()){
    					file.mkdir();
    				}
    				String apkFile = saveFileName;
    				File ApkFile = new File(apkFile);
    				FileOutputStream fos = new FileOutputStream(ApkFile);
    				
    				int count = 0;
    				byte buf[] = new byte[1024];
    				
    				do{   		   		
    		    		int numread = is.read(buf);
    		    		count += numread;
    		    	    progress =(int)(((float)count / length) * 100);
    		    	    //更新进度
    		    	    mHandler.sendEmptyMessage(DOWN_UPDATE);
    		    		if(numread <= 0){	
    		    			//下载完成通知安装
    		    			mHandler.sendEmptyMessage(DOWN_OVER);
    		    			break;
    		    		}
    		    		fos.write(buf,0,numread);
    		    	}while(!interceptFlag);//点击取消就停止下载.
    				
    				fos.close();
    				is.close();
    			} catch (MalformedURLException e) {
    				e.printStackTrace();
    			} catch(IOException e){
    				e.printStackTrace();
    			}
    			
    		}
    	};
    	
    	 /**
         * 下载apk
         * @param url
         */
    	
    	private void downloadApk(){
    		downLoadThread = new Thread(mdownApkRunnable);
    		downLoadThread.start();
    	}
    	 /**
         * 安装apk
         * @param url
         */
    	private void installApk(){
    		File apkfile = new File(saveFileName);
            if (!apkfile.exists()) {
                return;
            }    
            Intent i = new Intent(Intent.ACTION_VIEW);
            i.setDataAndType(Uri.parse("file://" + apkfile.toString()), "application/vnd.android.package-archive"); 
            mContext.startActivity(i);
    	
    	}
    }

第三步：在MainActivity.java也就是主Activity调用,代码如下:

package com.tutor.update;
    
    import android.app.Activity;
    import android.os.Bundle;
    
    public class MainAcitivity extends Activity {
        
    
    	private UpdateManager mUpdateManager;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            
            //这里来检测版本是否需要更新
            mUpdateManager = new UpdateManager(this);
            mUpdateManager.checkUpdateInfo();
        }     
    }

第四步：添加程序所用的资源与权限：

下载的时候用到了ProgressBar,所以事先写了一个progress.xml布局文件，代码如下:

<LINEARLAYOUT android:layout_height="wrap_content" android:layout_width="fill_parent" 						xmlns:android="http://schemas.android.com/apk/res/android">   
      		<PROGRESSBAR style="android: attr/progressBarStyleHorizontal" android:layout_height="wrap_content" android:layout_width="fill_parent" android:id="@+id/progress"> 										</PROGRESSBAR>										</LINEARLAYOUT>

下载的时候用到了网络部分，所以要在AndroidManifest.xml中添加网络权限，代码如下:

<USES-PERMISSION android:name="android.permission.INTERNET"></USES-PERMISSION>

第五步:运行查看效果如下:

图一:提示有最新包                                                                                   图二：点击开始下载

图三：下载完开始安装，我这里模拟器空间不足了。

![0_13319040024WuU.gif][]![0_1331904011i50n.gif][]![0_1331904024eK94.gif][]

[http_blog.csdn.net_android_tutor_article_details_7015986]: http://blog.csdn.net/android_tutor/article/details/7015986
[0_13319037812g3k.gif]: /images/20220613/aa282817ff8c49e1990f0d2455245430.png
[0_13319040024WuU.gif]: http://hi.csdn.net/attachment/201203/16/0_13319040024WuU.gif
[0_1331904011i50n.gif]: http://hi.csdn.net/attachment/201203/16/0_1331904011i50n.gif
[0_1331904024eK94.gif]: /images/20220613/09757e3585ad425c87193047cab6fce8.png