windows deployment of Qt<while Font class usage>

[smagesh89]

Hi All,

currently we are developing a Qt dll with Qfontmetrics and Qrawfont.
this has been created as shared library.

We will call this Qt dll from windows application to calculate the values.
This environment is working fine in the development PC where the Qt package is installed.

Rather, the below error is getting displayed in the PC which does not have Qt installed while executing this application.
Error Content:
This application failed to start because it could not find or load the qt platform plugin "windows".

We have checked blog and added the qwindows.dll as below, BUT still the problem not solved.

- Application.dll
- Required Qt dlls
- /plugins
-/platforms
- qwindows.dll
List of required dll set also placed below.
<Required Qt dlls>:
icudt51.dll
icudt52.dll
icuin51.dll
icuin52.dll
icuuc51.dll
icuuc52.dll
libEGL.dll
libEGLd.dll
libgcc_s_dw2-1.dll
libGLESv2.dll
libGLESv2d.dll
libKM_Harfbuzz.a
libstdc++-6.dll
libwinpthread-1.dll
Qt5Core.dll
Qt5Cored.dll
Qt5Gui.dll
Qt5Guid.dll
Qt5Sql.dll
Qt5Widgets.dll
Qt5Widgetsd.dll
QtCore4.dll

Could any one please tell me how to fix this issue.

-Magesh

[smagesh89]

Guys

Cud anyone pls recommend some methodology to overcome this issue.. plz..

[ars]

Hello,

some things that look strange to me:
1. Mixing debug and release dlls in the installation
2. Mixing Qt4 and Qt5 dlls (qtcore4 and qtcore5)

In the deployed folder of an application I have the following layout (entries with a + are folders):
+ bearer
+ imageformats
+ platforms
qwindows.dll
+ printsupport
+ styles
<application specific dlls and Qt library dlls>

Note that there is no plugins folder. However, when you look into the directory layout of the Qt development environment, the folders listed above are all under the plugins folder.

So if you have
+ plugins
+ platforms
qwindows.dll
in your installation change it to
+ platforms
qwindows.dll

You may also try windeployqt.exe (in your Qt5 development environment) to get an image for a deployed folder.
Hope that helps.

Best regards
ars

[smagesh89]

Hi ars,

I have tried that method as well.
still the error not resolved.

Can you pls provide any othr solution.
Thanks in advance!!!

[ars]

Hello,

if it is still not working, I would check/try the following:

1. Manually replace qwindows.dll on the non-development machine with a copy of the dll from the development machine. If it works now, the installed dll was damaged or was not compiled for the currently used Qt version.
2. Build a very simple Qt GUI program (without using any of your application dlls) and try to deploy it. In a first step, copy the binary into an empty folder and run windeployqt.exe on the binary. This will copy all required dlls into the folder. Then copy this folder to your non-development machine and try to run the binary there.
3. If step 2 succeeds, try to modify your installer to reproduce the deployed folder of the dummy binary. Try to get it to work on the non-development machine.

Sorry, I currently can't give you more hints.

Best regards
ars