monomer/tasks.md

• Done
  • Check events only for interested widgets (use focus for keyboard and region for mouse)
  • Add handling of disabled widget nodes
  • Add handling of custom external actions for widgets
  • Do something with return of custom handlers (the exact same thing we do with event handlers)
  • Add scroll support
  • Add hstack/vstack containers
  • Improve input (keyboard) handling
  • Implement copy/paste
  • Add HiDPI handling
  • Handle window resize
  • Improve handling of Color (turn to 0.0 to 1.0 instead of 0 to 255? only do it for alpha?)
  • Add handling of non visible widget nodes
  • Handle widget fixed size
  • Add good looking caret to textField
  • Add support for onFocus/onBlur
  • Maybe we don't need this and we can get by with position in render function?
    • Add support for onEnter/onLeave (keep track of previous active widgets)
    • We probably need it for drag&drop
  • How is the user going to provide state updates?
    • We already provide this with the State monad and corresponding lenses
  • Improve mouse support/current state of mouse and keyboard for event handling
  • Make handleEvent run inside MonadState (required to update user provided lenses) CANCELLED
  • Add logic that allows widgets to update user state
  • Does it make sense to avoid lenses internally, given that we already include the dependency?
  • How will long running (i.e., not immediate) user tasks will be handled?
  • Using local coordinates for widgets CANCELLED
    • How do we adjust current displacement?
  • Track drawing operations made by a Widget
    • Reorganize drawing operations
• Pending
  • Stop, think and design
    • How should all of this be organized?
    • How should modules be layed out?
    • What are good interfaces for the different parts of the system?
    • Does it make sense that handleEvent is the only pure function in a widget?
    • Based on the previous design, refactor modules
  • Current massive refactor
    • • Replace Tree with Containers' Tree
    • • Fix issue with event handling (click makes everything disappear)
    • • Fix focus situation (remove _focusRing and replace with single focus, then use _widgetNextFocusable)
    • • Provide focus to render (needed by textField)
    • • Check if resize children still makes sense (maybe the widget itself can resize on the corresponding event?)
    • • Handle SetFocus request
    • • Check if WidgetState is really needed
        • Maybe Data.Dynamic can be used, but currently abadoned
    • • Rethink Tree.Path import
    • • Clean up Seq imports
    • Can we generalize _widgetFind?
      • What for?
    • Where can we use Seq? Does it make sense to use it everywhere? What about Traversable?
    • Reorganize Common Types. What do other projects do? They should be simple to import and use
  • Create composite widget, on which application itself is based
  • Improve merge process. Implement Global keys
  • Improve hstack/vstack
    • If available space is greater than requested, do not apply resizing logic
  • Does a styling engine make sense or doing something similar to Flutter is simpler?
    • Does keeping style for some things (fixed width/height) make sense?
    • Could container handle padding and centering?
    • Implement styling engine. Think why Maybe Double instead of Maybe Dimension (to handle pixels, percent, etc)
  • Improve ergonomics
    • https://hackage.haskell.org/package/string-interpolate
    • Check if advanced type level features would improve the design
    • Check what syntax extensions can be abused to make life easier
      • https://limperg.de/ghc-extensions/#basic-patterns
      • https://limperg.de/ghc-extensions/#datakinds
      • Maybe -> https://typeclasses.com/extensions-intro
    • Look for ways that allow both lenses and user events to be used in the same widget
    • Related to previous, look for ways to simplify widget setup. Default instance with common values?
    • Find way of providing instance config (style, visibility, etc) before providing children (some sort of flip operator)
  • Keep sending mouse move event if mouse is away but button is still pressed
  • Fix scroll click navigation
  • Create layer widget to handle overlays/dialog boxes/tooltips (takes care of overlays)
  • Add text selection/editing to textField
  • Create Checkbox
  • Create Radio
  • Create Dropdown
  • Create Color Selector
  • Create Dialog
  • Create File Selector
  • Drag & drop for user (add attribute indicating if component supports being source/target)
    • Add new request types (drag started, drag stopped, drag cancelled)
    • Add new events (drag hover)
  • Implement SDL_Surface + Cairo backend
    • Can we cache some drawing operations?
  • Check if using lifted-async is worth it

What we have

Main Collects System Events Propagates System Events to Widgets Updates Widget hierarchy Collects App Events Calls App Events Handler Runs Widget Tasks Runs User Tasks Widget Consumes System Events Updates Internal State Creates new copy on handleEvent Generates App Events Generates Widget Tasks App Consumes App Events Generates User Tasks Updates Model

What we need/want

Create Data records for different types of Widget: StatelessWidget StatefulWidget StatelessContainer StatefulContainer

Composite

Main Collects System Events Propagates System Events to Widgets Updates Widget hierarchy Collects App Events Calls App Events Handler Runs Widget Tasks Runs User Tasks Widget Consumes System Events Updates Internal State Creates new copy on handleEvent Generates App Events Generates Widget Tasks App Consumes App Events Generates User Tasks Updates Model

Widget render draws itself calls children to draw themselves returns () handleSystemEvent handles own events decides if event is handled by its children returns maybe widget tree (if changes where made) app events system requests async tasks handleTaskResult returns maybe widget tree (if changes where made) app events system requests async tasks mergeWith (receives current state)

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