Qt resource not showing up in static build...

mzimmers

Yes my resource file looks similar to yours. The image displays when dynamically built, but not static.

kshegunov

Could you try with a static/debug just for the sake of it, to be honest I'm at a lost as you seem to have done everything right.

mzimmers

Static/debug doesn't display the image, either. So I'm doing something wrong with the inclusion of resources into a static build...?

kshegunov

Yes, this would be my best guess. Could you look inside the build folder and see if there's a file .rcc named after your qrc file? Perhaps it's not linked with the binary for some reason ...

mzimmers

No .rcc files anywhere. Well, thanks for looking; I guess I'll punt on this for awhile.

I did try another image type (.jpg) just to be sure...same results.

EDIT: I probably should point out that I have a warning associated with my static version of Qt: "No qmlscene installed." I really can't imagine that this is affecting anything, though.

kshegunov

No .rcc files anywhere. Well, thanks for looking; I guess I'll punt on this for awhile.

Sorry I couldn't be more helpful, perhaps someone else might have an idea, something I didn't think of.

mzimmers

I wonder...is it possible that this isn't Qt's fault? That the fault is somewhere within the toolchain? I guess I could try to build my app on Linux or a Mac to see...that'll take a little time, though. Just an idea...

kshegunov

Yes I guess it's a possibility, although probably a remote one. MSVC or MinGW? Because if it's mingw I'd expect it to behave pretty much the same as linux's g++. I'd compile it for you on linux, but the trouble is I don't keep static Qt builds around, I don't believe in static builds so to speak ...

EDIT:
Waaaaaiiit!
Did you load the image plugins in your binary with Q_IMPORT_PLUGIN?

mzimmers

@kshegunov it's MinGW. This isn't an area I'm especially knowledgeable in, but it seems that it's the toolchain (specifically the linker) that decides what does and doesn't go into an executable.

By the way, if you avoid static images, how do you deliver standalone apps to customers?

mrjj

@mzimmers said in Qt resource not showing up in static build...:

By the way, if you avoid static images, how do you deliver standalone apps to customers?

You can use an install maker
to deliver the .exe and its support dlls.
Qt even has its own tool
http://doc.qt.io/qtinstallerframework/

Static linking requires a Qt license so many of us , do it via an installer.

kshegunov

@mzimmers said in Qt resource not showing up in static build...:

By the way, if you avoid static images, how do you deliver standalone apps to customers?

One of the ways is to compile them in the binary, but as @mrjj noted you can also use an external (compiled) resource file and also you could possibly use an installer that delivers them raw in folders.
What about the Q_IMPORT_PLUGIN question?

mzimmers

@kshegunov I didn't see your plugin question until now...the answer is no, I didn't do that.

What exactly is the plug-in here: the .svg file, or the .qrc file that identifies it?

kshegunov

Aha, it may be the reason why it can't load the image; your issue might've been completely unrelated to the resource file.

The plugin is a library - and extension to Qt - that is loaded when your program starts. Plugins provide means to access different 3rd party file/image formats, databases and such. It's usually not needed to care about it when you use dynamic Qt build, because Qt will take care to load it at the appropriate time, however because of technical reasons this is not possible when Qt is build statically (and with static plugins) and you need to do the initialization manually.

mzimmers

So, I added this to main.cpp:

    Q_IMPORT_PLUGIN(qsvg);

And this to my .pro file:

QTPLUGIN += qsvg

I now get a build error:

C:\Users\MZimmers\Qt projects\removed\main.cpp:-1: error: undefined reference to `qt_static_plugin_qsvg()'

So, do I need to build and use a library in order to take advantage of this feature?

kshegunov

@mzimmers said in Qt resource not showing up in static build...:

So, do I need to build and use a library in order to take advantage of this feature?

Yes, the plugin itself. See what you have in <QtBase>/plugins/imageformats (I have a list of them one of which is libqsvg.so) you should have your plugins there (you'd expect to see .lib files)? If there are not then you haven't built them and that'd be the reason why the linker is complaining.

mzimmers

OK, I think we're zeroing in on this. My build of Qt with dynamic libraries is in:

C:\Qt\5.9.1\mingw53_32\plugins\imageformats

And all the .dlls are indeed there.

When I built my static version, I put it in \Qt\Static. Somehow, the 5.9.1 directory remained empty, but I do have a directory:

C:\Qt\Static\plugins\imageformats

With all the necessary .a files.

So, maybe the problem is that I screwed something up when I built my static version of Qt?

mzimmers

I think we have a solution:

I read the 5.0 version of the plugins doc: http://doc.qt.io/qt-5/plugins-howto.html. The wording is a little different, but it seems that the Q_IMPORT_PLUGIN is used when you want to create your own plugins, not use pre-existing ones. So I removed that file and it builds. The static version now displays the .svg.

Thanks to all who helped...

kshegunov

@mzimmers said in Qt resource not showing up in static build...:

With all the necessary .a files.

Nope, there's no error. MinGW uses linux-style static binaries (i.e. .a not .lib as with MSVC).
I'm glad you solved your problem in the meantime!

leashi

@mzimmers

qt5
in .pro QTPLUGIN += qsvg
in main.cpp Q_IMPORT_PLUGIN(QSvgPlugin)

qt4
in .pro QTPLUGIN += qsvg
in main.cpp Q_IMPORT_PLUGIN(qsvg)

name changed