I experienced slowness on Android with offline usage of QNetworkAccessManager on a specific android device (not on all android devices). I tried with several NDK versions with the same results.
My comment for your issue may not be the best but as far as I can recall the general suggestion is to use QtQuick objects for mobile programming because the widgets may not support the usage of the mobile's GPU.
in linux I have never worrie about the drivers, but yes for the tools, especially for his architecture and permission, but all of it depend on the distribution
I always use this to setup my environment in linux
Tipos Debian, Ubuntu, LinuxMint
$ sudo dpkg --add-architecture i386
$ sudo apt-get update
$ sudo apt-get install libstdc++6:i386 libgcc1:i386 zlib1g:i386 libncurses5:i386 libc6:i386 lib32z1 libbz2-1.0:i386
Hi @Chobin , as @vladstelmahovsky said, you must to set the delegate's sizes, but your listview is horizontal, so you must set his width to 0 if cellVisible is false, on the other hand, if the listview's orientation is vertical you must set the height.
The listview dont use strict sizes for delegates, but it reserve the space that the component requires, and the listview dont use the visible property to relayout the content, therefore we must change the delegate size for relayout the listview content and really to hide the delegate
You can use animation behavior to achieve a nice effect