How to start Qt application development under Yocto

[hkh]

I have been reading blogs trying to figure out how to develop Qt applications for iMX6 under Yocto. I need to understand what the process is (I have not used Qt before).

I can build various Yocto images and run them on my Nitrogen6x board. For example, fsl-image-gui comes up with the GUI, and I can run qtdemo. When I try to run qtdemo from the console, it says it can't find (or connect) to X Server. Maybe the GUI is interfering?

I saw suggestions of using qte-in-use-image, but it appears that it has it's own problems (for example gstreamer may not be included, issues with X Server, etc). And, I am not sure if that resolves the issue I have with running the demo (and eventually running my own application).

I don't care about the GUI that comes with fsl-image-gui since I want to have my own application, but I need VPU and other hardware support for MIPI camera, H.264 compression, and other image processing tasks performed in hardware.

Can someone point me in the right direction?

Thanks,

[hkh]

I found this link:

EcoCAR2 - Run the provided Qt application example

and was able to kill the GUI, and start qtdemo only when HDMI was connected:

$ killall -9 matchbox-window-manager

$ export DISPLAY=:0.0

$ /usr/bin/Xorg ...

$ qtdemo

Now my questions are:

1. How do I make this the default power-up behavior (run a certain Qt application)

2. How do I select which display is used (HDMI, LCD, or both?)

3. How do I get started developing my Qt application

Thanks,