Mobile and Embedded

@Akshaya-Shanker said in Queries regarding Qt component development across platform:

Is it possible ?

Yes, build a library and build it for every platform you want to support.
https://doc.qt.io/qt-6/sharedlibrary.html
https://wiki.qt.io/How_to_create_a_library_with_Qt_and_use_it_in_an_application

Awesome, thank you for sharing!

@jabille said in Error: Protocol "https" is unknown:

Maybe that is why it is disabled?

No, it is there because Qt was built without SSL support. You need a Qt build with SSL support.

You can try this:
setAspectRatioMode(Qt::AspectRatioMode::KeepAspectRatioByExpanding);

@VAdrianK You can use the exemples that comes with qt if you have crosscompiled qt for the board

@Gojir4
Work thks!

@jsulm Yes I did add the needed permission in the AndroidManifest.xml file but still didn't work

Just tested:

OPENSSL_ROOT_DIR=/opt/homebrew/Cellar/openssl@3/3.3.2 /path_to_src/qt/qtbase/configure --openssl

and it worked.

Note that this is with a recent checkout of qtbase.

OK, the solution seems to be:

Create a Java class to inherit QtActivity. Reimplement onNewIntent there Use QJniEnvironment.registerNativeMethods() and Java 'native' methods to allow passing in the intent or the data from that intent to the C++ code.

The documentation on the site is still far below general Qt level, but improving since 6.7 which I massively appreciate and I only managed to solve this by switching from the 6.5 docs to the 6.7 docs.

Yes, I'm trying that now, since Windows 11 seems to have better integration than Windows 10 did. Ideally I don't want to be dependent on that, though, especially since I know what I'm after is doable (and I have done it, but I forget how).

This is an ongoing "project" at this point, and I haven't touched it since last year. What I'd like is for someone to be able to articulate how exactly the build works. I understand I need a "host build" initially. From that output I then build the device binaries -- but since Qt is not an "end product" but more of a middleware/development tool, I'm guessing there must be some extra toolchain that it builds as well for when I do actually build an application. So if I were to build on x86_64 Linux -> x86_64 mingw-w64, and then use the output of the mingw-w64 build to generate the device (aarch64 gnu) output...would that work? Or is that not how this operates?

I'm aware this is ancient history but I was running into this problem as well (I've corrected it) and feel it necessary to add a bit more context and my analysis of what I think is happening. Tl;dr I was able to correct the aforementioned error by running the sysroot-relativesymlinks.py script mentioned above, re-running the configure, and rebuilding.

As noted previously, symlinks doesn't quite fix everything and I also had to use the Python symlink script. What I noticed, though, after running symlinks the first time is that a few shared libraries (such as Dbus) were not being correctly re-linked. Specifically:

aaron@AUSTIN:~$ ls -l rpi-sysroot/lib/aarch64-linux-gnu/libdbus* -rw-r--r-- 1 aaron aaron 785514 Sep 16 2023 rpi-sysroot/lib/aarch64-linux-gnu/libdbus-1.a lrwxrwxrwx 1 aaron aaron 42 Sep 16 2023 rpi-sysroot/lib/aarch64-linux-gnu/libdbus-1.so -> /lib/aarch64-linux-gnu/libdbus-1.so.3.32.4 lrwxrwxrwx 1 aaron aaron 19 Sep 16 2023 rpi-sysroot/lib/aarch64-linux-gnu/libdbus-1.so.3 -> libdbus-1.so.3.32.4 -rw-r--r-- 1 aaron aaron 395336 Sep 16 2023 rpi-sysroot/lib/aarch64-linux-gnu/libdbus-1.so.3.32.4

Notice how libdbus-1.so is still pointing to my system's (aarch64) version of libdbus, which also did not exist, since my system is x86_64 -- so the link itself was bad. So just a reminder to ensure that all of the links in your sysroot do not point to anything outside of that sysroot.

Hopefully this helps any Googler in the future.

@jsulm
The cameras are detected but the Photo Resolution QLists are empty, this is the output:

D libappQMediaDevices_Format_arm64-v8a.so: Camera: "QCameraDevice(name=Rear Camera: 0, id=0, position=BackFace)" , isDefault: false D libappQMediaDevices_Format_arm64-v8a.so: Photo Resolutions: QList() D libappQMediaDevices_Format_arm64-v8a.so: Camera: "QCameraDevice(name=Front Camera: 1, id=1, position=FrontFace)" , isDefault: false D libappQMediaDevices_Format_arm64-v8a.so: Photo Resolutions: QList()

I already have what I need:

image.png

image.png

But Qt Creator requires additional packages. Can I disable showing the following message:

image.png

OK I got it working. After that last post, I decided to enable signing the package. After doing that, I'm able to build and run my application. I wish Qt would remind me/force me to sign the package before I hit build if it's required for me to sign the package because this has tripped me up in the past (very cryptic error message).

Anyway, thanks for all the help!

Hi

I think you have to uninstall everything and reinstall the free version of maintenance tool, and thus everything else behind (creator, design studio, Qt versions etc etc ...), and unless you request Qt to transfer your account to a free account and wait for them to respond, you will have to create a new account.

@kuroro-l First, your code has nothing to do with Qt. When you build it for Android, you need to pack gstreamer build(libs and plugins) for Android with your app.

If you want to use Qt sink in your pipeline, try to make a Qt GUI and use qml or widget sink in your pipeline. There are quite some posts about how to do it in this forum and gstreamer forum.