Adapt core UI components to declarative contracts

[Alex2772]

#465

• ADropdownList
• ASlider
• AGroupBox
• AScrollArea
• AScrollAreaViewport
• AScrollBar
• AListView
• Flyout button
  • https://learn.microsoft.com/en-us/windows/win32/uxguide/ctrl-list-boxes
  • https://learn.microsoft.com/en-us/windows/apps/develop/ui/controls/
  • https://learn.microsoft.com/en-us/windows/apps/develop/ui/controls/buttons#create-a-drop-down-button
  • https://learn.microsoft.com/en-us/windows/apps/develop/ui/controls/listview-and-gridview
  • https://learn.microsoft.com/en-us/windows/apps/design/controls/list-details
• ASpacerFixed
• ASpacerExpanding
• AProgressBar/ACircleProgressBar/ASpinnerV2 (should appear on the same page in docs)
• ATextField
• ATextArea
• ANumberPicker/ADoubleNumberPicker (should appear on the same page in docs)
• ADirChooserView/AFileChooserView (should appear on the same page in docs)

Also, not sure were should I put these thoughts, maybe put it here:

• TriStateCheckBox is required (by https://github.com/Alex2772/hackers-mc-launcher)
• Maybe reference implementation of ATreeView based of AUI_DECLARATIVE_FOR is needed (can be stolen from https://github.com/Alex2772/hackers-mc-launcher)
• In general, my experience was good, especially making reactive expressions with AUI_REACT. This really allows make view models with complex relationships between values, without bothering about triggering relevant UI updates. Although I still need to Button { ...} AUI_LET { connect(AUI_REACT(enable condition, AUI_SLOT(it)::setEnabled)); } and similar things, that was not described by declarative contract. Most common cases are:
  • setEnabled
  • setVisibility
  • setCustomStyle (Rethink global stylesheet approach #572 (comment))
  • setPosition/setSize