Android下载更新代码

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

//Start===========
public void updata(){
new Thread(){
@Override
public void run() {
request(apiUrl);
}
}.start();

}
String newapkName = "updata.apk";
String apiUrl = "http://192.168.1.101:8080/udate.txt";
//请求接口
public void request(String Httpurl){
URL url = null;
try {
url = new URL(Httpurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
InputStream is = conn.getInputStream();
String s = toString(is);
JSONObject jsonObject = new JSONObject(s);
Double versionCode = jsonObject.getDouble("versionCode"); //远程版本
String versionName = getVersionName();
double v = Double.parseDouble(versionName);
if(versionCode > v){
//更新下载
downLoadFile(jsonObject.getString("updateurl"));

}
} catch (Exception e) {
e.printStackTrace();
}

}
Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
switch (msg.what){
case 1:
ShowUpdataDilg();
break;

}
}
};
//版本提示对话框
public void ShowUpdataDilg() {
new AlertDialog.Builder(MainActivity.this)
.setTitle("提示")
.setMessage("是否安装最新版本？ ")
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Uodate();
}
})
.setNegativeButton("取消", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {

}
})
.show();
}

//获取版本
private String getVersionName() throws Exception
{
PackageManager packageManager = getPackageManager();
// getPackageName()是你当前类的包名，0代表是获取版本信息
PackageInfo packInfo = packageManager.getPackageInfo(getPackageName(),0);
String version = packInfo.versionName;
return version;
}

//安装apk
public void Uodate(){
//        String str = "/" + newapkName;
//        String fileName = Environment.getExternalStorageDirectory() + str;
//        Intent intent = new Intent(Intent.ACTION_VIEW);
//        intent.setDataAndType(Uri.fromFile(new File(fileName)), "application/vnd.android.package-archive");
//        startActivity(intent);

String str = "/sdcard/update/" + newapkName;
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(str)),
"application/vnd.android.package-archive");
startActivity(intent);

}

//对话框确定
public void isUpdate(){
String str = "/" + newapkName;
String fileNames = Environment.getExternalStorageDirectory() + str;
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(fileNames)), "application/vnd.android.package-archive");
startActivity(intent);

}

protected File downLoadFile(String httpUrl) {
File tmpFile = new File("/sdcard/update");
if (!tmpFile.exists()) {
tmpFile.mkdir();
}
final File file = new File("/sdcard/update/" + newapkName);

try {
URL url = new URL(httpUrl);
try {
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
InputStream is = conn.getInputStream();
FileOutputStream fos = new FileOutputStream(file);
byte[] buf = new byte[256];
conn.connect();
double count = 0;
if (conn.getResponseCode() >= 400) {
Toast.makeText(MainActivity.this, "连接超时", Toast.LENGTH_SHORT).show();
} else {
while (count <= 100) {
if (is != null) {
int numRead = is.read(buf);
if (numRead <= 0) {
break;
} else {
fos.write(buf, 0, numRead);
}
} else {
break;
}
}
}
fos.close();
is.close();
conn.disconnect();
//下载成功
handler.sendEmptyMessage(1);
} catch (IOException e) {
e.printStackTrace();
}
} catch (MalformedURLException e) {
e.printStackTrace();
}
return file;
}
//输入流转换为String
public String toString(InputStream is) {
String result = null;
try {
//构造一个输出流(字节队列输出流)
ByteArrayOutputStream baos = new ByteArrayOutputStream();
//一个byte数组，用来存储得到的字节数据
byte[] bys = new byte[1024];
int len = 0;
//循环读出完整字节数据
while((len = is.read(bys)) != -1) {
baos.write(bys,0,len);
}
//byte数据转换为字符串
result = new String(baos.toByteArray());
is.close();
baos.close();

} catch (IOException e) {
e.printStackTrace();
}
return result;
}
//End===========