我已经查看了其他一些具有类似标题的线程,但似乎没有一个能够解决我的问题。所以,到此为止。
我正在使用Google市场扩展文件(apkx)库和示例代码,只需进行一些修改。此代码依赖于从处理后台下载,许可证检查等的服务接收回调。
我有一个错误,服务无法正确连接,导致软锁。为了使这个更无益,这个bug在某些设备上永远不会发生,但在其他设备上大约有三分之二的时间发生。我相信它独立于Android版本,当然我有两个设备运行2.3.4,其中一个(一个Nexus S)没有问题,另一个(HTC Evo 3D)没有。
要尝试连接到服务,请调用bindService并返回true。然后按预期调用OnBind并返回一个合理的值但是(当错误发生时)onServiceConnected不会发生(我等了20分钟以防万一)。
还有其他人见过这样的事吗?如果没有,我可能做了什么导致这种行为的猜测?如果没有人有任何想法,我明天会发布一些代码。
编辑:这是相关代码。如果我错过了什么,请问。
在添加此代码的同时,我发现了一个小错误。修复它导致我正在尝试解决的问题的频率从3次中的2次变为6次在手机上的大约1次我正在测试它;不知道对其他手机的影响。这继续向我提出一个竞争条件或类似情况,但我不知道是什么。
OurDownloaderActivity.java(从Google示例代码中复制和更改)
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
//Test the licence is up to date
//if (current stored licence has expired)
{
startLicenceCheck();
initializeDownloadUI();
return;
}
...
}
@Override
protected void onResume() {
if (null != mDownloaderClientStub) {
mDownloaderClientStub.connect(this);
}
super.onResume();
}
private void startLicenceCheck()
{
Intent launchIntent = OurDownloaderActivity.this
.getIntent();
Intent intentToLaunchThisActivityFromNotification = new Intent(OurDownloaderActivity
.this, OurDownloaderActivity.this.getClass());
intentToLaunchThisActivityFromNotification.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK |
Intent.FLAG_ACTIVITY_CLEAR_TOP);
intentToLaunchThisActivityFromNotification.setAction(launchIntent.getAction());
if (launchIntent.getCategories() != null) {
for (String category : launchIntent.getCategories()) {
intentToLaunchThisActivityFromNotification.addCategory(category);
}
}
// Build PendingIntent used to open this activity from Notification
PendingIntent pendingIntent = PendingIntent.getActivity(OurDownloaderActivity.this,
0, intentToLaunchThisActivityFromNotification,
PendingIntent.FLAG_UPDATE_CURRENT);
DownloaderService.startLicenceCheck(this, pendingIntent, OurDownloaderService.class);
}
initializeDownloadUI()
{
mDownloaderClientStub = DownloaderClientMarshaller.CreateStub
(this, OurDownloaderService.class);
//do a load of UI setup
...
}
//This should be called by the Stub's onServiceConnected method
/**
* Critical implementation detail. In onServiceConnected we create the
* remote service and marshaler. This is how we pass the client information
* back to the service so the client can be properly notified of changes. We
* must do this every time we reconnect to the service.
*/
@Override
public void onServiceConnected(Messenger m) {
mRemoteService = DownloaderServiceMarshaller.CreateProxy(m);
mRemoteService.onClientUpdated(mDownloaderClientStub.getMessenger());
}
DownloaderService.java(在谷歌市场扩展库中,但有些编辑)
//this is the onBind call that happens fine; the value it returns is definitely not null
@Override
public IBinder onBind(Intent paramIntent) {
return this.mServiceMessenger.getBinder();
}
final private IStub mServiceStub = DownloaderServiceMarshaller.CreateStub(this);
final private Messenger mServiceMessenger = mServiceStub.getMessenger();
//MY CODE, derived from Google's code
//I have seen the bug occur with a service started by Google's code too,
//but this code happens more often so is more repeatably related to the problem
public static void startLicenceCheck(Context context, PendingIntent pendingIntent, Class<?> serviceClass)
{
String packageName = serviceClass.getPackage().getName();
String className = serviceClass.getName();
Intent fileIntent = new Intent();
fileIntent.setClassName(packageName, className);
fileIntent.putExtra(EXTRA_LICENCE_EXPIRED, true);
fileIntent.putExtra(EXTRA_PENDING_INTENT, pendingIntent);
context.startService(fileIntent);
}
@Override
protected void onHandleIntent(Intent intent) {
setServiceRunning(true);
try {
final PendingIntent pendingIntent = (PendingIntent) intent
.getParcelableExtra(EXTRA_PENDING_INTENT);
if (null != pendingIntent)
{
mNotification.setClientIntent(pendingIntent);
mPendingIntent = pendingIntent;
} else if (null != mPendingIntent) {
mNotification.setClientIntent(mPendingIntent);
} else {
Log.e(LOG_TAG, "Downloader started in bad state without notification intent.");
return;
}
if(intent.getBooleanExtra(EXTRA_LICENCE_EXPIRED, false))
{
//we are here due to startLicenceCheck
updateExpiredLVL(this);
return;
}
...
}
}
//MY CODE, based on Google's, again
public void updateExpiredLVL(final Context context) {
Context c = context.getApplicationContext();
Handler h = new Handler(c.getMainLooper());
h.post(new LVLExpiredUpdateRunnable(c));
}
private class LVLExpiredUpdateRunnable implements Runnable
{
LVLExpiredUpdateRunnable(Context context) {
mContext = context;
}
final Context mContext;
@Override
public void run() {
setServiceRunning(true);
mNotification.onDownloadStateChanged(IDownloaderClient.STATE_LVL_UPDATING);
String deviceId = getDeviceId(mContext);
final APKExpansionPolicy aep = new APKExpansionPolicy(mContext,
new AESObfuscator(getSALT(), mContext.getPackageName(), deviceId));
// Construct the LicenseChecker with a Policy.
final LicenseChecker checker = new LicenseChecker(mContext, aep,
getPublicKey() // Your public licensing key.
);
checker.checkAccess(new LicenseCheckerCallback() {
...
});
}
}
DownloaderClientMarshaller.java(在Google市场扩展库中)
public static IStub CreateStub(IDownloaderClient itf, Class<?> downloaderService) {
return new Stub(itf, downloaderService);
}
和来自同一文件的Stub类:
private static class Stub implements IStub {
private IDownloaderClient mItf = null;
private Class<?> mDownloaderServiceClass;
private boolean mBound;
private Messenger mServiceMessenger;
private Context mContext;
/**
* Target we publish for clients to send messages to IncomingHandler.
*/
final Messenger mMessenger = new Messenger(new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_ONDOWNLOADPROGRESS:
Bundle bun = msg.getData();
if ( null != mContext ) {
bun.setClassLoader(mContext.getClassLoader());
DownloadProgressInfo dpi = (DownloadProgressInfo) msg.getData()
.getParcelable(PARAM_PROGRESS);
mItf.onDownloadProgress(dpi);
}
break;
case MSG_ONDOWNLOADSTATE_CHANGED:
mItf.onDownloadStateChanged(msg.getData().getInt(PARAM_NEW_STATE));
break;
case MSG_ONSERVICECONNECTED:
mItf.onServiceConnected(
(Messenger) msg.getData().getParcelable(PARAM_MESSENGER));
break;
}
}
});
public Stub(IDownloaderClient itf, Class<?> downloaderService) {
mItf = itf;
mDownloaderServiceClass = downloaderService;
}
/**
* Class for interacting with the main interface of the service.
*/
private ServiceConnection mConnection = new ServiceConnection() {
//this is the critical call that never happens
public void onServiceConnected(ComponentName className, IBinder service) {
// This is called when the connection with the service has been
// established, giving us the object we can use to
// interact with the service. We are communicating with the
// service using a Messenger, so here we get a client-side
// representation of that from the raw IBinder object.
mServiceMessenger = new Messenger(service);
mItf.onServiceConnected(
mServiceMessenger);
mBound = true;
}
public void onServiceDisconnected(ComponentName className) {
// This is called when the connection with the service has been
// unexpectedly disconnected -- that is, its process crashed.
mServiceMessenger = null;
mBound = false;
}
};
@Override
public void connect(Context c) {
mContext = c;
Intent bindIntent = new Intent(c, mDownloaderServiceClass);
bindIntent.putExtra(PARAM_MESSENGER, mMessenger);
if ( !c.bindService(bindIntent, mConnection, 0) ) {
if ( Constants.LOGVV ) {
Log.d(Constants.TAG, "Service Unbound");
}
}
}
@Override
public void disconnect(Context c) {
if (mBound) {
c.unbindService(mConnection);
mBound = false;
}
mContext = null;
}
@Override
public Messenger getMessenger() {
return mMessenger;
}
}
DownloaderServiceMarshaller.java(在Google市场扩展库中,未更改)
private static class Proxy implements IDownloaderService {
private Messenger mMsg;
private void send(int method, Bundle params) {
Message m = Message.obtain(null, method);
m.setData(params);
try {
mMsg.send(m);
} catch (RemoteException e) {
e.printStackTrace();
}
}
public Proxy(Messenger msg) {
mMsg = msg;
}
@Override
public void requestAbortDownload() {
send(MSG_REQUEST_ABORT_DOWNLOAD, new Bundle());
}
@Override
public void requestPauseDownload() {
send(MSG_REQUEST_PAUSE_DOWNLOAD, new Bundle());
}
@Override
public void setDownloadFlags(int flags) {
Bundle params = new Bundle();
params.putInt(PARAMS_FLAGS, flags);
send(MSG_SET_DOWNLOAD_FLAGS, params);
}
@Override
public void requestContinueDownload() {
send(MSG_REQUEST_CONTINUE_DOWNLOAD, new Bundle());
}
@Override
public void requestDownloadStatus() {
send(MSG_REQUEST_DOWNLOAD_STATE, new Bundle());
}
@Override
public void onClientUpdated(Messenger clientMessenger) {
Bundle bundle = new Bundle(1);
bundle.putParcelable(PARAM_MESSENGER, clientMessenger);
send(MSG_REQUEST_CLIENT_UPDATE, bundle);
}
}
private static class Stub implements IStub {
private IDownloaderService mItf = null;
final Messenger mMessenger = new Messenger(new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_REQUEST_ABORT_DOWNLOAD:
mItf.requestAbortDownload();
break;
case MSG_REQUEST_CONTINUE_DOWNLOAD:
mItf.requestContinueDownload();
break;
case MSG_REQUEST_PAUSE_DOWNLOAD:
mItf.requestPauseDownload();
break;
case MSG_SET_DOWNLOAD_FLAGS:
mItf.setDownloadFlags(msg.getData().getInt(PARAMS_FLAGS));
break;
case MSG_REQUEST_DOWNLOAD_STATE:
mItf.requestDownloadStatus();
break;
case MSG_REQUEST_CLIENT_UPDATE:
mItf.onClientUpdated((Messenger) msg.getData().getParcelable(
PARAM_MESSENGER));
break;
}
}
});
public Stub(IDownloaderService itf) {
mItf = itf;
}
@Override
public Messenger getMessenger() {
return mMessenger;
}
@Override
public void connect(Context c) {
}
@Override
public void disconnect(Context c) {
}
}
/**
* Returns a proxy that will marshall calls to IDownloaderService methods
*
* @param ctx
* @return
*/
public static IDownloaderService CreateProxy(Messenger msg) {
return new Proxy(msg);
}
/**
* Returns a stub object that, when connected, will listen for marshalled
* IDownloaderService methods and translate them into calls to the supplied
* interface.
*
* @param itf An implementation of IDownloaderService that will be called
* when remote method calls are unmarshalled.
* @return
*/
public static IStub CreateStub(IDownloaderService itf) {
return new Stub(itf);
}