Thanks all your kind help in this summer, finally my GUI is working well.
The following may be the last problem， it’s not important, but hopefully can be solved in some way.
when the panda window generated, I can use my cursor to adjust its size, like most other applications (e.g., the chrome browser). However, if I change the size, the models rendered in the window seems not change together, therefore, if I downscale the window size, the models on the edge can not be seen any more.
It is not important, but it will be better if solved.
Finally, thanks the kind forums. I’m sorry for many stupid problems, but you are always kind to help me. Also sorry for my English, I’m grateful that you can understand my meaning.
Sincerely, I really like this 3D engine and this summer.