Qt Quick UI design

You can use Qt Quick Designer to design Qt Quick based UIs in the Design mode.

Creating UI logic	Turn your wireframe into an interactive prototype by adding UI logic that lets your components apply actions or react to mock data from backend systems to simulate complex experiences.
Optimizing designs	Solve performance problems by optimizing graphical assets.
Production quality	Fine-tune your UI for production.
UI files	Limitations of UI files (.ui.qml).
Using QML modules with plugins	Use C++ plugins to expose custom components to Qt Quick applications.