Today I came across a very strange error with QWebView which I cannot resolve myself.
I included a QWebView widget in my application. When I set a URL or a piece of HTML code to display (with QWebView::setUrl() or QWebView::setHtml()), it works very well on my machine. It also works on all machines that have Qt installed, but not on those without it. I compiled a release build and included all necessary libraries as shared (QtWebKit4.dll, QtNetwork4.dll etc.), so I guess my error lies in that I forgot to include some libraries.
If anybody has already had such an error, I would be very grateful for help!
You might need to include the relevant Qt image processing plugin libraries, which are located in qt/plugins/imageformats (and maybe also qt/plugins/iconengines ). I haven't deployed any webkit apps, so I'm not certain about this.
See my answer to this question: Qt dll deployment on windows
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For some reason, I want to publish my application as a portable one. That is, avoiding the pre-installed shared libraries and use my own ones, shipped together with the app.
Long story short. Following the advises on this helpful page, I found that the window icon, which is an svg, not showing up in the foreign computer. What did I miss?
Turns out a shared library it needs cannot be found.
In Windows, you have to put Qt5Svg.dll in the same folder of the exe. And in Linux, besides the libQt5Svg.so.5, iconengines/libqsvgicon.so is also needed.
I set a background image(JPEG) on a Qt widget using setStyleSheet(). This is perfectly shown on my computer, but not on another computer.
I am not getting a link error on the other computer -- the feature just doesn't work. Is there something I am missing in the distribution or build of my app, something that the Qt dev tools installs or is otherwise available, that isn't present on other machines? How can I distribute a Qt app that uses JPEG functionality?
JPEG support in Qt comes as a plugin. Make sure you have also deployed the plugin to your non-development machine. If you haven't, it will simply silently fail and you'll end up not seeing any of the JPEG images. Have a look at the official documentation for more detailed information: http://qt-project.org/doc/qt-4.8/deployment-windows.html
In short (and as a quick solution, but have a look at the documentation as well) you could create a directory named "imageformats" as a subdirectory of the folder containing your exe, into which you copy QJPEG4.dll.
I’ve tried to build the directshow multimedia plugin in Qt5 under Windows7, however, there is a problem that qedit.h is not found, as this file was removed from WindowsSDK 7.1 (which is the one I am required to use to build Qt5).
So I tried to follow this post here.
Just adding this qedit.h (from what I see it just needs the IID_ISampleGrabber and CLSID_SampleGrabber and that’s it) and recompiling. It linked alright, but when I run my application, if I try to play video it just doesn’t do a damn thing, and if I try to access the camera it just quits the application right away. Since I have no idea about the inner workings of DS, I don’t know how legitimate this fix is.
How do I fix this?
Thanks.
I am trying to build QtCore.lib and I get this weird error.
PRJ0019: A tool returned an error code from "MOC kernel\qtimer.cpp"
I am able to build qtmain.lib but not able tp go any further.
moc.exe is available in bin folder and the path is added to my PATH.
kernel\qtimer.cpp file is also present in corelib folder.
Any help in this regard will be appreciated. I am building with Qt-4.5.2 source.
In Qt 4.5.2 moc.exe has some issues. An email I sent to Qt Support mentions it moc'ing files that were not modified. It could have further issues, which could be related to what you are experiencing.
Sorry I can't recall the exact details. To make things worse the link Qt Support had sent me at the time is broken.
They had suggested using 4.5.3. I think we ended up staying on 4.5.1, which we are still using today, although the move to 4.7.x. is occurring as I write this. :)
Basically I am trying to load the image as a texture using QPixmap:
texture[T_WALL] = bindTexture(QPixmap(":/images/wall.png"), GL_TEXTURE_2D);
The code works on my development machine, but not in the vm / other pcs without QT. Initially I was using jpegs and just assumed that I messed up the plugins, but as I understand, no plugins are needed for png files so I have no idea where the problem is.
Results are the same when loading local files and using Qt resources.
I am deploying libgcc_s_dw2-1.ddl, mingwm10.dll, QtCore4.dll, QtGui4.dll, QtOpenGL4.dll. Do I need anything else?
Try adding an imageformats directory to your application directory and put qmng4.dll there. See my answer to the question Qt dll deployment on windows
If it still does not work, get the Sysinternals suite which contains dgbview.exe that allows you to watch qDebug messages (even for release builds).