Is there any possibility to hide the annoying popup in the xml editors preview which says there are rendering problems?
It overlaps half of the preview
Rule of thumb: don't fix the symptom, fix the problem!
You only get this when you are using custom views. In this case, in your custom view Java file, you should have a section like the below to give the renderer data to work with.
if(!this.isInEditMode()) {
this.setTypeface(Typeface.createFromAsset(context.getAssets(),"appFont.otf"););
}
This will set the typeface to "appFont.otf" when the renderer is trying to render your custom view in the preview window.
Hope this helps!