Get and set the selected state of a gadget.
This attribute can be triggered by the user
clicking on the gadget (or using the keyboard),
depending on the input mode:
- MUIV_InputMode_RelVerify:
- set when lmb is pressed.
- cleared when lmb is released.
- cleared when the gadget is selected and the
mouse leaves the gadget box.
- set when the mouse reenters the gadget box.
- MUIV_InputMode_Immediate:
- MUIV_InputMode_Toggle:
- toggled when lmb is pressed.
Of course you may set this attribute yourself, e.g.
to adjust the state of a checkmark gadget.
A selected gadget will display its border reverse
and get the configured MUII_SelectedBack background.
This can be avoided using the MUIA_ShowSelState tag.