Mobile and Embedded

The java code had a memory leak in the code: public String execute(String channelName) { // String [] value = new String[50]; double [] pv_data = new double[50]; try { // initialize context //initialize(); Context context = null; JCALibrary jca = JCALibrary.getInstance(); context = jca.createContext(JCALibrary.CHANNEL_ACCESS_JAVA); // Create the Channel to connect to the PV. Channel channel = context.createChannel(channelName); .... .... .... // calling this before returning solved issue context.destroy();

Hi and welcome to devnet, You might be asking questions for situations that may have not been encountered yet. They are indeed interesting. I would suggest bringing them to the interest mailing list. You'll find there Qt's developers/maintainers. This forum is more user oriented.

You seem to use a version of the emsdk that is not mentioned in the Qt for Web Assembly wiki entry. Did you try to use one of these ?

Ok, then it would have been better to explain that from the start. What size is your database ? If not too big, you can put it in Qt's resources system and then copy that file from the resource to a suitable location given by QStandardPaths. You may have to create the folder given before copying the database file over there.

Hi again, I could not figure out how to retrieve this clipped area, I searched about setting margin of plotting area but no success. However at least, I managed to show points label totally with these codes; series->setPointLabelsVisible(true); series->setPointLabelsColor(Qt::black); series->setPointLabelsClipping(false); series->setPointLabelsFormat("@yPoint"); Maybe that helps to others ! Thanks

Someone might have ideas if you told in detail what your device is.

@Pablo-J-Rogina I will look into it.

Yes you are right I should have thought of that! The screen goes blank when system is idle as the app is an activity it stays on I modified my systemd/login.conf to go into suspend mode when idle for 30 sec. now the screen goes blank and the system remains suspended. It may not be the most ideal solution but it is a temporary fix till I get to the bottom of it. Thank you for the support

I manually compiled QtMultimedia and copied libQtMultimediaQuick.so (and related libs) and qml folder of the compiled module to RPi and it works. But has lags in Camera qml component. Never mind :)

That's not a problem. That's just gentle, professional informing that if you should have any problems they may be due to a version of SDK that Qt hasn't been tested with yet.

Something is not clear, are you getting that behaviour on your desktop machine or your Android target ? By the way, depending on what you are currently building, on mobile, you might want to consider using QtQuick.

@ketank16 said in No such plugin: 'socketcan' on BeagleBone Black: it was quite simple actually. glad you found the solution. Could the post be marked as solved? Thanks.

@goldlovemoon said in QT5.9.6 build in ARM EC-A3399C: why not build opengl in virtual machine, then transplant environment to arm I'm not sure I understand your question. When cross compiling for a different architecture you need a crosscompiler and sysroot for your device. A virtual machine will not help here. I guess your host machine is x86, right? That means, to build for ARM you need a compiler running on x86 but generating binaries for ARM. And you need sysroot containing the stuff from the file system of your device (libs, include files).

@swood If I change the version code of one of the versions google play says the the version with the older version code will be completely overshadowed. Not true. You must use different version codes. Use a different range for each platform. For example armv7: [1, 1000], armv8: [1001, 2000]. It can get pretty complicated if you have to support a lot of architectures and features. See: https://developer.android.com/google/play/publishing/multiple-apks.html#VersionCodes

@pablo-j-rogina too sad. but commenting is still possible. just to show the interest...

@alleycat said in Qt not connecting through SSH to a BeagleBone Black: I am trying to set up a Kit in Qt. Although you didn't state your Qt Creator version, you may be facing the condition shown in this post for Qt Creator >= 4.9.x It looks like the solution/workaround is using the key pair approach in SSH.

@mark81 said in Hints for web-application with Qt5 server-side code: @j-hilk Thanks for the link. I think these classes are very useful for communications between the client and the server. The only point that is still missing is the server-side code to generate dynamic content. You have, say 1200 parameters (well, the actual application has more) to display and let the user to edit them. In PHP you can query the data from the database, page the records, write the HTML code on the fly and push to the client. How would you do the same with Qt5? Or, if it's not worth to, how to pass the data to the PHP scripts so they can create the dynamic web-page? I'm sorry, that is not really my forte. I know classes exists, So I linked them, but I haven't used them myself yet