我正在尝试运行一种在后台检查应用程序更新的方法，但出现以下错误，我想我缺少一些要导入的包，但我对此不太确定。在这方面我将非常感谢你。
Errors <br>
lastUpdateTime cannot be resolved to a variable
checkUpdate cannot be resolved
Illegal modifier for the variable checkUpdate; only final is permitted
showUpdate cannot be resolved to a variable
Illegal modifier for the variable showUpdate; only final is permitted
这是我的代码
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
SharedPreferences prefs = getPreferences(0);
lastUpdateTime = prefs.getLong("lastUpdateTime", 0);
/* Should Activity Check for Updates Now? */
if ((lastUpdateTime + (24 * 60 * 60 * 1000)) < System.currentTimeMillis()) {
/* Save current timestamp for next Check*/
lastUpdateTime = System.currentTimeMillis();
SharedPreferences.Editor editor = getPreferences(0).edit();
editor.putLong("lastUpdateTime", lastUpdateTime);
editor.commit();
/* Start Update */
checkUpdate.start();
/* This Thread checks for Updates in the Background */
private Thread checkUpdate = new Thread() {
public void run() {
try {
URL updateURL = new URL("url to my company");
URLConnection conn = updateURL.openConnection();
InputStream is = conn.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int current = 0;
while((current = bis.read()) != -1){
baf.append((byte)current);
}
/* Convert the Bytes read to a String. */
final String s = new String(baf.toByteArray());
/* Get current Version Number */
int curVersion = getPackageManager().getPackageInfo("your.app.id", 0).versionCode;
int newVersion = Integer.valueOf(s);
/* Is a higher version than the current already out? */
if (newVersion > curVersion) {
/* Post a Handler for the UI to pick up and open the Dialog */
mHandler.post(showUpdate);
}
} catch (Exception e) {
}
}
};