@mrjj If it works with setters, it should be fine. I'm relatively new to Qt and since you have signals and slots, I thought using setters is maybe not the best way, so there MUST be another solution :) haha Ok I will try it out tomorrow and let you know if it worked for me :) EDIT: @mrjj @SGaist Thank you guys, passing the pointer to my data with constructor and setting the data to a local member to use it inside my WindowChildClass worked for me.