Android 最简单的更新机制 UpdateManager

public class UpdateManager {

	private Context mContext;
	
    //提示语
    private String updateMsg = "有最新的软件包，请更新系统";

    //返回的安装包url
    private String apkUrl = "";
    
    private Dialog noticeDialog;

    private Dialog downloadDialog;
     /* 下载包安装路径 */
    private static final String savePath = 
    		Environment.getExternalStorageDirectory().getPath() + "/ziruk/";

    private static final String saveFileName = savePath + "UpdateZirukRelease.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(String url){
    	String URLRoot = HttpBaseCls.GetURLRoot(mContext);
    	this.apkUrl = URLRoot + url;
        showNoticeDialog();
    }

    private void showNoticeDialog(){
        Builder builder = new Builder(mContext);
        builder.setTitle("软件版本更新");
        builder.setMessage(updateMsg);
        builder.setCancelable(false);
        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(){
        Builder builder = new Builder(mContext);
        builder.setTitle("软件版本更新");
        builder.setCancelable(false);
        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);
                if(!file.exists()){
                	file.createNewFile();
                }
                
                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) {
            	Log.e("UpdateManager", e.getMessage());
            } catch(IOException e){
            	Log.e("UpdateManager", e.getMessage());
            }

        }
    };

     /**
     * 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);

    }
}