How to run external QT program from PyQT5 on MacOS

Benjamin Halko · wrote on 17 Jan 2022, 16:43

@jsulm Yeah finder is installed. By Finder rather than MacOS do you mean telling finder to open Dolphin Emulator rather than just tell MacOS to open it?

Oh and Dolphin works just fine when running it from Finder normally, it is just when I launch it using subprocess.Popen that is the trouble.

SGaist · 17 Jan 2022, 20:02

From the looks of it, we are talking about very different software.

"Dolphin" is known to be the KDE file manager. So from the looks of it you are trying to start something very different. Can you give more details about what it is ? And what exactly you are trying to do with your application ?

Benjamin Halko · S SGaist 17 Jan 2022, 18:47

@SGaist I am wanting to open the Dolphin Emulator from my app as well as tell it to load a game using the -e argument that it accepts. However since Dolphin is also a QT program when trying to run it using subprocess, it tries loading both sets of libraries (from my app and Dolphin)

SGaist · 18 Jan 2022, 00:33

What if you use the QProcess::startDetached method ?

Benjamin Halko · S SGaist 17 Jan 2022, 20:10

@SGaist Ok so I tried and nothing happened! But then I tried using the executable located in /Contents/MacOS/Dolphin
and it gave me this:

objc[2357]: Class QMacAutoReleasePoolTracker is implemented in both /Users/benjamin/Desktop/Dolphin.app/Contents/Frameworks/QtCore.framework/Versions/5/QtCore (0x10b53a9f8) and /private/var/folders/50/g29zbzlx4fb85zh8kk4g6gm40000gn/T/_MEIYRjNbS/QtCore (0x10efe8198). One of the two will be used. Which one is undefined.
objc[2357]: Class QT_ROOT_LEVEL_POOL__THESE_OBJECTS_WILL_BE_RELEASED_WHEN_QAPP_GOES_OUT_OF_SCOPE is implemented in both /Users/benjamin/Desktop/Dolphin.app/Contents/Frameworks/QtCore.framework/Versions/5/QtCore (0x10b53aa70) and /private/var/folders/50/g29zbzlx4fb85zh8kk4g6gm40000gn/T/_MEIYRjNbS/QtCore (0x10efe8210). One of the two will be used. Which one is undefined.
objc[2357]: Class KeyValueObserver is implemented in both /Users/benjamin/Desktop/Dolphin.app/Contents/Frameworks/QtCore.framework/Versions/5/QtCore (0x10b53aa98) and /private/var/folders/50/g29zbzlx4fb85zh8kk4g6gm40000gn/T/_MEIYRjNbS/QtCore (0x10efe8238). One of the two will be used. Which one is undefined.
objc[2357]: Class RunLoopModeTracker is implemented in both /Users/benjamin/Desktop/Dolphin.app/Contents/Frameworks/QtCore.framework/Versions/5/QtCore (0x10b53aae8) and /private/var/folders/50/g29zbzlx4fb85zh8kk4g6gm40000gn/T/_MEIYRjNbS/QtCore (0x10efe8288). One of the two will be used. Which one is undefined.
QObject::moveToThread: Current thread (0x7faab1e065c0) is not the object's thread (0x7faab1c17ed0).
Cannot move to target thread (0x7faab1e065c0)

You might be loading two sets of Qt binaries into the same process. Check that all plugins are compiled against the right Qt binaries. Export DYLD_PRINT_LIBRARIES=1 and check that only one set of binaries are being loaded.
qt.qpa.plugin: Could not load the Qt platform plugin "cocoa" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: cocoa, minimal, offscreen, webgl.

This was the code I used:

launch = QProcess()
launch.startDetached(dolphinPath+"/Contents/MacOS/Dolphin")

Benjamin Halko · S SGaist 17 Jan 2022, 20:10

@SGaist Oh by the way, this issue only occurs when the program is packaged with pyinstaller, running it regularly works just fine.

SGaist · wrote on 19 Jan 2022, 19:12

What exactly are you packaging ?

Benjamin Halko · wrote on 19 Jan 2022, 23:43

Here is my project folder. Here is the actual run dolphin function. Hope that helps.

SGaist · 22 Jan 2022, 19:01

Did you try to use Popen with shell=True ?

Benjamin Halko · S SGaist 21 Jan 2022, 19:33

@SGaist It gave the same error LSOpenURLsWithRole() failed with error -10810 for the file /Users/benjamin/Desktop/Dolphin.app.

Oh and I tried starting the .app not executable in /Contents/MacOS/

SGaist · 22 Jan 2022, 23:40

Which version of Qt are your application and Dolphin using ?

Benjamin Halko · S SGaist 22 Jan 2022, 20:04

@SGaist I am using PyQt5 (I think version 5.12.2) And I have been informed that Dolphin uses 5.15.0 (C++). Although it seems that Dolphin uses this custom version ...maybe???

SGaist · 26 Jan 2022, 19:56

You should try with both using the same version of Qt.

Benjamin Halko · wrote on 25 Jan 2022, 22:20

My bad I was using PyQt5 version 5.15.5, but I will still try using Dolphins version.

Benjamin Halko · 27 Jan 2022, 07:36

@SGaist Ok so I update PyQt5 and I used ['open', '/Users/benjamin/Desktop/Dolphin.app/Contents/MacOS/Dolphin'],shell=False and it worked!
But then when I went to use ['open', '/Users/benjamin/Desktop/Dolphin.app/Contents/MacOS/Dolphin', '--args', '-e', gamePath],shell=False to try to load a game, it gave me the open command usage dialog. Is there something wrong with using --args?
Also I tried things like opening with just /Users/benjamin/Desktop/Dolphin.app or using shell=True but they also didn't work...

I wonder if the arguments for Dolphin only work when running from the Dolphin.app and not the /Contents.... one.
Took a look and yep, the /Contents one doesn't support arguments...

jsulm · 27 Jan 2022, 20:23

@Benjamin-Halko said in How to run external QT program from PyQT5 on MacOS:

Is there something wrong with using --args?

I don't know.
What exactly does "command usage dialog" tell you? You're probably using --args wrongly.

Benjamin Halko · 28 Jan 2022, 07:27

@jsulm It is just what it gives you when you just type open.

Also, when launching the .app from Python, Dolphin starts then immediately crashes with this error message using Apples Crash Message Screen Thing: https://pastebin.com/NqBK0YvQ (It also shows LSOpenURLsWithRole() failed with error -10810 for the file /Users/benjamin/Desktop/Dolphin.app. in the terminal window)

jsulm · wrote on 28 Jan 2022, 07:27

@Benjamin-Halko As I said you first need to find out how to call Dolphin properly.
Try to pass it -h parameter to get more information.