版本更新demo

public class AutoUpdate {
	public Activity activity = null;
	private static final String TAG = "AutoUpdate";
	private String currentFilePath = "";
	private String currentTempFilePath = "";
	private String fileEx = "";
	private String fileNa = "";
	private String strURL = "";
	private ProgressDialog dialog;

	// 构造方法
	public AutoUpdate(Activity activity, String url) {
		this.activity = activity;
		this.strURL = url;
	}

	// 判断网络是不是连接
	public void check(String clientversion) {
		if (isNetworkAvailable(this.activity) == false) {
			return;
		}
		if (true) {
			// Check version.
			if (!getCurrentVersion().versionName.equals(clientversion))
				showUpdateDialog();
		}
	}

	// 判断网络连接方法
	public static boolean isNetworkAvailable(Context ctx) {
		try {
			ConnectivityManager cm = (ConnectivityManager) ctx
					.getSystemService(Context.CONNECTIVITY_SERVICE);
			NetworkInfo info = cm.getActiveNetworkInfo();
			return (info != null && info.isConnected());
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		}
	}

	// 询问是否更新
	public void showUpdateDialog() {
		@SuppressWarnings("unused")
		AlertDialog alert = new AlertDialog.Builder(this.activity)
				.setTitle("Title")
				.setIcon(R.drawable.ic_launcher)
				.setMessage("Update or not?")
				.setPositiveButton("Update",
						new DialogInterface.OnClickListener() {
							public void onClick(DialogInterface dialog,
									int which) {
								downloadTheFile(strURL);
								showWaitDialog();
							}
						})
				.setNegativeButton("Cancel",
						new DialogInterface.OnClickListener() {
							public void onClick(DialogInterface dialog,
									int which) {
								dialog.cancel();
								Intent mIntent = new Intent();
								mIntent.setClass(activity,
										NavigaterActivity.class);
								activity.startActivity(mIntent);
								activity.finish();
							}
						}).show();
	}

	// 弹出等待更新框
	public void showWaitDialog() {
		dialog = new ProgressDialog(activity);
		dialog.setMessage("Waitting for update...");
		dialog.setIndeterminate(true);
		dialog.setCancelable(true);
		dialog.show();
	}

	// 获取当前版本号码和名称
	public PackageInfo getCurrentVersion() {

		PackageInfo info = null;
		try {
			info = activity.getPackageManager().getPackageInfo(
					activity.getPackageName(), 0);

		} catch (NameNotFoundException e) {
			e.printStackTrace();
		}
		return info;
	}

	// 下载apk包
	private void downloadTheFile(final String strPath) {
		fileEx = strURL.substring(strURL.lastIndexOf(".") + 1, strURL.length())
				.toLowerCase();
		fileNa = strURL.substring(strURL.lastIndexOf("/") + 1,
				strURL.lastIndexOf("."));
		try {
			if (strPath.equals(currentFilePath)) {
				doDownloadTheFile(strPath);
			}
			currentFilePath = strPath;
			Runnable r = new Runnable() {
				public void run() {
					try {
						doDownloadTheFile(strPath);
					} catch (Exception e) {
						Log.e(TAG, e.getMessage(), e);
					}
				}
			};
			new Thread(r).start();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	// 下载
	private void doDownloadTheFile(String strPath) throws Exception {
		Log.i(TAG, "getDataSource()");
		if (!URLUtil.isNetworkUrl(strPath)) {
			Log.i(TAG, "getDataSource() It's a wrong URL!");
		} else {
			URL myURL = new URL(strPath);
			URLConnection conn = myURL.openConnection();
			conn.connect();
			InputStream is = conn.getInputStream();
			if (is == null) {
				throw new RuntimeException("stream is null");
			}
			File myTempFile = File.createTempFile(fileNa, "." + fileEx);
			currentTempFilePath = myTempFile.getAbsolutePath();
			FileOutputStream fos = new FileOutputStream(myTempFile);
			byte buf[] = new byte[128];
			do {
				int numread = is.read(buf);
				if (numread <= 0) {
					break;
				}
				fos.write(buf, 0, numread);
			} while (true);
			Log.i(TAG, "getDataSource() Download  ok...");
			dialog.cancel();
			dialog.dismiss();
			openFile(myTempFile);
			try {
				is.close();
			} catch (Exception ex) {
				Log.e(TAG, "getDataSource() error: " + ex.getMessage(), ex);
			}
		}
	}

	// 打开文件
	private void openFile(File f) {
		Intent intent = new Intent();
		intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
		intent.setAction(android.content.Intent.ACTION_VIEW);
		String type = getMIMEType(f);
		intent.setDataAndType(Uri.fromFile(f), type);
		activity.startActivity(intent);
	}

	// 删除文件
	public void delFile() {
		Log.i(TAG, "The TempFile(" + currentTempFilePath + ") was deleted.");
		File myFile = new File(currentTempFilePath);
		if (myFile.exists()) {
			myFile.delete();
		}
	}

	// 判断文件类型
	private String getMIMEType(File f) {
		String type = "";
		String fName = f.getName();
		String end = fName
				.substring(fName.lastIndexOf(".") + 1, fName.length())
				.toLowerCase();
		if (end.equals("m4a") || end.equals("mp3") || end.equals("mid")
				|| end.equals("xmf") || end.equals("ogg") || end.equals("wav")) {
			type = "audio";
		} else if (end.equals("3gp") || end.equals("mp4")) {
			type = "video";
		} else if (end.equals("jpg") || end.equals("gif") || end.equals("png")
				|| end.equals("jpeg") || end.equals("bmp")) {
			type = "image";
		} else if (end.equals("apk")) {
			type = "application/vnd.android.package-archive";
		} else {
			type = "*";
		}
		if (end.equals("apk")) {
		} else {
			type += "/*";
		}
		return type;
	}

}