Qt Mobility Bluetooth fix
Kate Alhola
kate.alhola at gmail.com
Fri Dec 14 09:51:38 UTC 2012
I got first fixed version to work with my application, fix is not yet
perfect and a lot of clean up is needed. The other key issue
was that there was missing several env->NewGlobalRef() when references were
shared between different methods and also
some smaller issues.
Then couple of questions
1- To supply fixes and improvements, what is recommend method. It looks
that all commits were done by BogDan
should I just supply diffs as file. Or is there possible to clone
personal repository on quickgit.kde.org and
then let BogDan merge fixes when he approves them ?
2- For testing,is there some easy way override ministro supplied libraries
with my own until final code
is integrated to ministro ? CurrentlyI have tested just doing adb push
to /data/data/org.kde.ministro
but that needs to have rooted device.
¨
Kate
On Wed, Dec 12, 2012 at 4:21 PM, Kate Alhola <kate.alhola at gmail.com> wrote:
> Hi, I have finally had time to look this issue. The problem clearly is
> that JNI_OnLoad is running on different thread thanJavaVM instance. I Tried
> quick fix with
> int status = m_jvm->AttachCurrentThread(&env, NULL) but it does not solve
> problem because code is running on different thread agan.
>
> It looks that only fix is to add JNIEnv* env to all Bluetooth private
> classes like class QBluetoothLocalDevicePrivate and then use
> >AttachCurrentThread to get environment
> because it is still possible to run bluetooth in different thread than
> QApplication .
>
>
> Kate
>
>
> On Thu, Nov 8, 2012 at 1:52 PM, Lauri Laanmets <
> lauri.laanmets at proekspert.ee> wrote:
>
>> Hi
>>
>> I'm quite sure you are on the right track. I remember I used to do quite
>> a lot of things in "JNI_OnLoad " because only in that case it was possible
>> to access the Necessitas Java classes. I remember an e-mail about
>> redesigning that part, to be able to access Necessitas Java classes also
>> from other threads. I would suspect something has changed in this field. I
>> started working on it but since my "/local/data" is inaccessible, I kind of
>> a "lost a little motivation".
>>
>> Can anybody comment, are Necessitas Java classes now available also in
>> the other threads?
>>
>> Lauri
>>
>>
>>
>> On 8.11.2012 13:39, Kate Alhola wrote:
>>
>> Hi, I have been doing little bit research about this issue. I just under
>> investigation one simple function QBluetoothLocaldevice::name().
>> The function crashes if vm->GetEnv() is done in JINI_OnLoad() . When I
>> moved that code inside of QBluetoothLocaldevice constructor
>> code works. I have not yet made any patches, this was just result of
>> simple experiment.
>>
>> I tried in some other code do same allocations in JINI_OnLoad and got
>> errors that VM was allocated for wrong thread.
>> It looks that JINI_OnLoad is too early phase to allocate
>>
>> Before going forward with fix, I just like hear opinion am I at right
>> track. The bthost is my experimental class
>> just to test code. initJini is called from constructor. Name() duplicates
>> function from QBluetoothLocalDevice
>>
>> Then other related question, if I do patched libQtConnectivity, what is
>> best way to use it ? Necessitas always
>> installs it's own and it can't be copied over without rooting the device.
>>
>>
>> Kate
>>
>> void BtHost::initJini()
>> {
>> void* venv = NULL;
>>
>> qDebug() << "BtHost:JNI_OnLoad()";
>> if (m_jvm->GetEnv(&venv, JNI_VERSION_1_4) != JNI_OK)
>> {
>> qDebug() << "Qt:GetEnv failed";
>> return;
>> }
>> jclass qtApplicationC;
>> env = reinterpret_cast<JNIEnv*>(venv);
>> btAdapterClass = env->FindClass("android/bluetooth/BluetoothAdapter");
>> if (btAdapterClass == NULL)
>> {
>> qDebug() << "Qt:Native registration unable to find class
>> android/bluetooth/BluetoothAdapter";
>> }
>>
>> jmethodID getDefaultAdapterID =env->GetStaticMethodID(btAdapterClass,
>> "getDefaultAdapter", "()Landroid/bluetooth/BluetoothAdapter;");
>> if(getDefaultAdapterID == NULL){
>> qDebug() << "Qt:Native registration unable to get method ID:
>> getDefaultAdapter of android/bluetooth/BluetoothAdapter";
>> }
>>
>> btAdapterObject = env->CallStaticObjectMethod(btAdapterClass,
>> getDefaultAdapterID);
>> if(btAdapterObject == NULL){
>> qDebug() << "Qt:Device does not support Bluetooth";
>> }
>> btAdapterObject = env->NewGlobalRef(btAdapterObject);
>> }
>>
>> QString BtHost::name() const
>> {
>> qDebug() << " BtHost::name()";
>> static jmethodID getNameID = env->GetMethodID(btAdapterClass,
>> "getName", "()Ljava/lang/String;");
>> qDebug() << " QBluetoothLocalDevice::name() env->GetMethodID";
>> jstring peerName = (jstring)
>> env->CallObjectMethod(btAdapterObject, getNameID);
>> qDebug() << " QBluetoothLocalDevice::name()
>> env->CallObjectMethod";
>> jboolean isCopy;
>> const jchar* name = env->GetStringChars(peerName, &isCopy);
>> QString qtName = QString::fromUtf16(name,
>> env->GetStringLength(peerName));
>> qDebug() << " QBluetoothLocalDevice::name() name=" << qtName;
>> env->ReleaseStringChars(peerName, name);
>> qDebug() <<" QBluetoothLocalDevice::name() exit";
>> return qtName;
>>
>>
>> }
>>
>>
>>
>>
>> On Thu, Nov 1, 2012 at 7:29 PM, Kate Alhola <kate.alhola at gmail.com>wrote:
>>
>>> On Mon, Oct 29, 2012 at 10:59 PM, Micke Prag <micke.prag at telldus.se>wrote:
>>>
>>>> Hi,
>>>>
>>>> It only happens after I call start(). Only creating the object works
>>>> fine.
>>>> Thank you for looking into this.
>>>>
>>>
>>> I noticed that exactly same thing happens with QBluetoothSocket and
>>> QBluetoothLocalDevice, in both cases they happen If I try use some member
>>> functions. Creation of object goes OK in both of cases. I posted report to
>>> android-qt list but may be this is better forum.
>>>
>>> Here is two cases where I got same bug
>>>
>>> Code:
>>> qDebug() << "Turning bluetooth on";
>>> localDevice->powerOn();
>>>
>>> D/Qt ( 4746): Turning bluetooth on
>>>
>>> E/dalvikvm( 4746): JNI ERROR (app bug): accessed stale local reference
>>> 0x9f50001d (index 7 in a table of size 4)
>>>
>>> E/dalvikvm( 4746): VM aborting
>>>
>>> Or
>>>
>>> from:
>>> wmSocket = new QBluetoothSocket(
>>> QBluetoothSocket::RfcommSocket);
>>>
>>> qDebug() << "btHost::tryConnect()" << wmPulse.address().toString()
>>> << ":" << PORT;
>>> wmSocket->connectToService(wmPulse.address(), PORT);
>>>
>>> D/Qt ( 6195): btHost::tryConnect() "83:7C:82:00:39:31" : 5
>>>
>>> E/dalvikvm( 6195): JNI ERROR (app bug): accessed stale local reference
>>> 0xb3b0001d (index 7 in a table of size 0)
>>>
>>> E/dalvikvm( 6195): VM aborting
>>>
>>>
>>> Kate
>>>
>>>
>>>
>>>>
>>>> Regards
>>>> Micke
>>>>
>>>> On Monday 29 October 2012 at 21:54, Lauri Laanmets wrote:
>>>>
>>>> Hi
>>>>
>>>> I guess that is addressed to me :). Crash is definitely a bug,
>>>> regardless of Android permissions or missing Java files. Can you verify if
>>>> it crashes on creating the DiscoveryAgent object or when starting the
>>>> discovery?
>>>>
>>>> I have lost my old devel set-up, It takes me a few days to get on that
>>>> issue.
>>>>
>>>> Regards
>>>> Lauri
>>>>
>>>>
>>>> On 29.10.2012 22:31, Micke Prag wrote:
>>>>
>>>> Hello,
>>>>
>>>> I know that the Bluetooth support in Necessitas is not complete but I
>>>> wanted to try it out anyway. I am only trying to discover bluetooth devices
>>>> but my application crashes. I don't know if I am doing something wrong or
>>>> if it is not supported yet?
>>>>
>>>> The output from logcat can be found here: http://pastebin.com/khcj28Xy
>>>> This is what I am doing:
>>>> QtMobility::QBluetoothDeviceDiscoveryAgent agent;
>>>> agent.start();
>>>>
>>>> libs.xml:
>>>> <?xml version='1.0' encoding='utf-8'?>
>>>> <resources>
>>>> <array name="qt_libs">
>>>> <item>QtCore</item>
>>>> <item>QtGui</item>
>>>> <item>QtNetwork</item>
>>>> <item>QtDeclarative</item>
>>>> <item>QtXml</item>
>>>> <item>QtOpenGL</item>
>>>> <item>QtSystemInfo</item>
>>>> <item>QtConnectivity</item>
>>>> </array>
>>>> <array name="bundled_libs"/>
>>>> </resources>
>>>>
>>>> I also have this in AndroidManifest.xml:
>>>> <uses-permission android:name="android.permission.BLUETOOTH" />
>>>>
>>>> Bluetooth is activated on the device.
>>>>
>>>> The device is a Cube U30GT-H running Android 4.1.1
>>>>
>>>> --
>>>> Micke Prag
>>>>
>>>>
>>>> _______________________________________________
>>>> Necessitas-devel mailing listNecessitas-devel at kde.orghttps://mail.kde.org/mailman/listinfo/necessitas-devel
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Necessitas-devel mailing list
>>>> Necessitas-devel at kde.org
>>>> https://mail.kde.org/mailman/listinfo/necessitas-devel
>>>>
>>>>
>>>
>>
>>
>> _______________________________________________
>> Necessitas-devel mailing list
>> Necessitas-devel at kde.org
>> https://mail.kde.org/mailman/listinfo/necessitas-devel
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/necessitas-devel/attachments/20121214/b1863817/attachment-0001.html>
More information about the Necessitas-devel
mailing list