What do you want to achieve?
Modify flags or states of widgets based on previous state.
Take my recent project (a complex menu) for instance. Multiple buttons and corresponding operational panels are designed within a screen. In this situation, I must handle flags and states of buttons and panels very carefully.
- When button A is clicked, corresponding panel A will appear (remove hidden flag);
- Remove “
Clickable” flag of Button A, add “Clickable” flag and remove “Checked” state to all other buttons since I don’t know whether it is the first time that a user click Button A or it is clicked after other button. - Add “
Hidden” flag to all other panels (again, you don’t know user operation sequence).
All steps have to be done in the CLICK event of each button.
I exported the code to testing platform and do a trial run, it turns out that the screen response is very slow. I have to optimize the “State” and “Flag” handling in the event function.
If the flag, state modification is conditional, event handling function will be more efficient without code modification.
Do you see alternative options and workaround to achieve it?
Currently, you can only do conditional flag/state modification in the exported LVGL code.
Mention some use cases
Complex menu GUI design.