Did you make it finally work? I got stocked with the exact same problem.
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I didnt read your code with much attention, but for starters if all you want is draw a triangle, check this tutorials I did https://bitbucket.org/joaodeusmorgado/opengltutorials
I'm using vbos, to draw triangles. I'm using all OpenGL native calls, but should be pretty easy to convert to Qt OpenGL functions. I also recommend you this book wich is great, it has a lot of details that usually are ommited in other books http://alfonse.bitbucket.org/oldtut/index.html
Then you should use the Qt resource system to embed the shader in your application. You current shader files are accessible on your host. When you start your application on your device, they won't be there.
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