QFileDialog::getOpenFilename shows a Qt dialog instead of native dialog on Linux

[n-elie]

Issue: QFileDialog::getOpenFilename shows a Qt dialog instead of native dialog when using Qt from conda-forge. The native dialog shows up if using system Qt or Qt from anaconda channel. On Windows, with the conda-forge Qt, the native dialog is also used.

This simple example can be used to reproduce the problem:

#include <QApplication>
#include <QFileDialog>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QFileDialog::getOpenFileName();
    return a.exec();
}

Any idea what's wrong?

Environment (conda list):

``` $ conda list # packages in environment at /home/nicolas/miniconda3/envs/qt-conda-forge: # # Name Version Build Channel _libgcc_mutex 0.1 conda_forge conda-forge _openmp_mutex 4.5 0_gnu conda-forge ca-certificates 2020.4.5.1 hecc5488_0 conda-forge certifi 2020.4.5.1 py38h32f6830_0 conda-forge dbus 1.13.6 he372182_0 conda-forge expat 2.2.9 he1b5a44_2 conda-forge fontconfig 2.13.1 h86ecdb6_1001 conda-forge freetype 2.10.1 he06d7ca_0 conda-forge gettext 0.19.8.1 hc5be6a0_1002 conda-forge glib 2.58.3 py38h73cb85d_1004 conda-forge gst-plugins-base 1.14.5 h0935bb2_2 conda-forge gstreamer 1.14.5 h36ae1b5_2 conda-forge icu 64.2 he1b5a44_1 conda-forge jpeg 9c h14c3975_1001 conda-forge ld_impl_linux-64 2.34 h53a641e_0 conda-forge libclang 9.0.1 default_hde54327_0 conda-forge libffi 3.2.1 he1b5a44_1007 conda-forge libgcc-ng 9.2.0 h24d8f2e_2 conda-forge libgomp 9.2.0 h24d8f2e_2 conda-forge libiconv 1.15 h516909a_1006 conda-forge libllvm9 9.0.1 hc9558a2_0 conda-forge libpng 1.6.37 hed695b0_1 conda-forge libstdcxx-ng 9.2.0 hdf63c60_2 conda-forge libuuid 2.32.1 h14c3975_1000 conda-forge libxcb 1.13 h14c3975_1002 conda-forge libxkbcommon 0.10.0 he1b5a44_0 conda-forge libxml2 2.9.10 hee79883_0 conda-forge ncurses 6.1 hf484d3e_1002 conda-forge nspr 4.25 he1b5a44_0 conda-forge nss 3.47 he751ad9_0 conda-forge openssl 1.1.1f h516909a_0 conda-forge pcre 8.44 he1b5a44_0 conda-forge pip 20.0.2 py_2 conda-forge pthread-stubs 0.4 h14c3975_1001 conda-forge python 3.8.2 h8356626_5_cpython conda-forge python_abi 3.8 1_cp38 conda-forge qt 5.12.5 hd8c4c69_1 conda-forge readline 8.0 hf8c457e_0 conda-forge setuptools 46.1.3 py38h32f6830_0 conda-forge sqlite 3.30.1 hcee41ef_0 conda-forge tk 8.6.10 hed695b0_0 conda-forge wheel 0.34.2 py_1 conda-forge xorg-libxau 1.0.9 h14c3975_0 conda-forge xorg-libxdmcp 1.1.3 h516909a_0 conda-forge xz 5.2.5 h516909a_0 conda-forge zlib 1.2.11 h516909a_1006 conda-forge ```

Details about conda and system ( conda info ):

``` $ conda info active environment : qt-conda-forge active env location : /home/nicolas/miniconda3/envs/qt-conda-forge shell level : 2 user config file : /home/nicolas/.condarc populated config files : /home/nicolas/.condarc conda version : 4.8.3 conda-build version : 3.18.11 python version : 3.7.4.final.0 virtual packages : __glibc=2.31 base environment : /home/nicolas/miniconda3 (writable) channel URLs : https://conda.anaconda.org/rdkit/linux-64 https://conda.anaconda.org/rdkit/noarch https://conda.anaconda.org/bioconda/linux-64 https://conda.anaconda.org/bioconda/noarch https://conda.anaconda.org/conda-forge/linux-64 https://conda.anaconda.org/conda-forge/noarch https://repo.anaconda.com/pkgs/main/linux-64 https://repo.anaconda.com/pkgs/main/noarch https://repo.anaconda.com/pkgs/r/linux-64 https://repo.anaconda.com/pkgs/r/noarch package cache : /home/nicolas/miniconda3/pkgs /home/nicolas/.conda/pkgs envs directories : /home/nicolas/miniconda3/envs /home/nicolas/.conda/envs platform : linux-64 user-agent : conda/4.8.3 requests/2.23.0 CPython/3.7.4 Linux/5.4.27-1-MANJARO manjaro/19.0.2 glibc/2.31 UID:GID : 1000:1001 netrc file : None offline mode : False ```

[hmaarrfk]

i'm not too sure. Maybe we can check for differences in the recipes?

[hmaarrfk]

i was just wondering if other people were hitting the same thing.