android app版本更新简介

一、访问服务器，获取最新版的版本信息

/** 获取服务端版本号 */
public static int getVersion(String url) {
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(url);

HttpResponse response;
try {
response = client.execute(get);
//连接成功
if (200 == response.getStatusLine().getStatusCode()) {
InputStream in = response.getEntity().getContent();
//将版本文件下载到指定的位置
File file = new File(Environment.getExternalStorageDirectory()
.toString() + "/version.xml");
FileOutputStream fos = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int len;
while ((len = in.read(buffer)) != -1) {
fos.write(buffer, 0, len);
}
fos.flush();
in.close();
fos.close();
FileInputStream fis = new FileInputStream(file);
//对版本文件进行XML解析
int code = parseXml(fis);
return code;
}

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return 0;
}XML解析的方法可参考如下，根据不同的xml格式需部分修改本方法:
private static int parseXml(InputStream is) {
int code = 0;
XmlPullParser parser = Xml.newPullParser();
try {
parser.setInput(is, "utf-8");
int eventType = parser.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
switch (eventType) {
case XmlPullParser.START_DOCUMENT:
break;
case XmlPullParser.START_TAG:
String tag = parser.getName();
if ("VERSION".equals(tag)) {
String codeStr = parser.nextText().trim();
code = Integer.parseInt(codeStr.substring(0, 1));
}
if ("SIZE".equals(tag)) {
String len = parser.nextText().trim();
leng = Long.parseLong(len);
}
break;
default:
break;
}
eventType = parser.next();
}

} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return code;
}

二、根据获取到的最新版本号，与当前使用版本进行比较，如需升级则进行如下操作。
从服务器端获取最新安装包，方法如下：

/** 获取最新安装包 */
public static void getApk(String url) {
HttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet(url);
HttpResponse response;
try {
response = client.execute(get);
if (200 == response.getStatusLine().getStatusCode()) {
InputStream in = response.getEntity().getContent();
//将安装包下载到本地
File file = new File(Environment.getExternalStorageDirectory()
.toString() + "/xxx/version/xxx.apk");
FileOutputStream fos = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int len;
while ((len = in.read(buffer)) != -1) {
fos.write(buffer, 0, len);
int rate = (int) (file.length() * 100 / leng);
//此处可进行UI更新
}
fos.flush();
in.close();
fos.close();
return;
}

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return;
}三、下载完安装包可直接进行安装，安装方法如下:
// 安装apk
protected void installApk(File file) {
Intent intent = new Intent();
// 执行动作
intent.setAction(Intent.ACTION_VIEW);
// 执行的数据类型
intent.setDataAndType(Uri.fromFile(file),
"application/vnd.android.package-archive");
startActivity(intent);
}