mirror of
https://github.com/gui-cs/Terminal.Gui.git
synced 2025-12-26 15:57:56 +01:00
a84b2c4896
* WIP: Broken
* Got working. Mostly.
* Parllel tests pass
* More progres
* Fixed app tests.
* Mouse
* more progress.
* working on shortcut
* Shortcut accept on ENTER is broken.
* One left...
* More test progress.
* All unit tests pass. Still some issues though.
* tweak
* Fixed Integration Tests
* Fixed UI Catalog
* Tweaking CP to try to find race condition
* Refactor StandardColors and improve ColorPicker logic
Refactored `StandardColors` to use lazy initialization for static fields, improving performance and avoiding static constructor convoy effects. Introduced `NamesValueFactory` and `MapValueFactory` methods for encapsulated initialization logic.
Simplified `GetColorNames` to directly return `_names.Value`. Improved `TryParseColor` by clarifying default value usage and adopting object initializer syntax. Updated `TryNameColor` to use `_argbNameMap.Value`.
Refactored `GetArgb` for better readability. Replaced `MultiStandardColorNameResolver` with `StandardColorsNameResolver` in `ColorPicker`. Commented out `app.Init("Fake")` in `ColorPickerTests` for testing purposes.
Made minor formatting improvements, including updated comments and XML documentation for consistency.
* revert
* Throttle input loop to prevent CPU spinning
Introduce a 20ms delay in the input loop of `InputImpl<TInputRecord>`
to prevent excessive CPU usage when no input is available. Removed
the `DateTime dt = Now();` line and the `while (Peek())` block, which
previously enqueued input records.
This change improves resource management, especially in scenarios
where multiple `ApplicationImpl` instances are created in parallel
tests without calling `Shutdown()`. It prevents thread pool
exhaustion and ensures better performance in such cases.
* Refactor ApplicationImpl to use IDisposable pattern
Implemented the IDisposable pattern in ApplicationImpl to improve resource management. Added `Dispose` and `DisposeCore` methods, and marked the `Shutdown` method as obsolete, encouraging the use of `Dispose` or `using` statements instead. Updated the `IApplication` interface to inherit from IDisposable and added `GetResult` methods for retrieving run session results.
Refactored unit tests to adopt the new lifecycle management approach, replacing legacy `Shutdown` calls with `Dispose` or `using`. Removed fragile and obsolete tests, and re-enabled previously skipped tests after addressing underlying issues.
Updated `FakeApplicationLifecycle` and `SetupFakeApplicationAttribute` to align with the new disposal pattern. Improved documentation and examples to guide users toward modern usage patterns. Maintained backward compatibility for legacy singleton usage.
* Add IDisposable pattern with input loop throttling
- Add IDisposable to IApplication for proper resource cleanup
- Add 20ms throttle to input loop (prevents CPU spinning)
- Add Lazy<T> to StandardColors (eliminates convoy effect)
- Add MainLoopCoordinatorTests suite (5 new tests)
- Add Dispose() calls to all 16 ColorPickerTests
- Mark Application.Shutdown() as [Obsolete]
IApplication now requires Dispose() for cleanup
Performance: 100x CPU reduction, 15x faster disposal, tests complete in <5s
Fixes: Thread leaks, CPU saturation, test hangs in parallel execution
Docs: Updated application.md and newinv2.md with disposal patterns
* Refactor test for input loop throttling clarity
Updated `InputLoop_Throttle_Limits_Poll_Rate` test to improve clarity, reliability, and efficiency:
- Rewrote summary comment to clarify purpose and emphasize the 20ms throttle's role in preventing CPU spinning.
- Replaced `var` with explicit types for better readability.
- Reduced test duration from 1s to 500ms to improve test speed.
- Revised assertions:
- Replaced range-based assertion with upper-bound check to ensure poll count is below 500, avoiding timing sensitivity issues.
- Added assertion to verify the thread ran and was not immediately canceled.
- Added a 2-second timeout to `inputTask.Wait` and verified task completion.
- Improved comments to explain test behavior and reasoning behind changes.
* tweaks
* Fix nullabiltiy stuff.
* runnable fixes
* more nullabe
* More nullability
* warnings gone
* Fixed fluent test failure.
* Refactor ApplicationImpl and update Runnable layout logic
Refactored `ApplicationImpl.Run.cs` for improved readability and
atomicity:
- Combined `if (wasModal)` with `SessionStack?.TryPop` to streamline
logic.
- Simplified restoration of `previousRunnable` by reducing nesting.
- Updated comments for clarity and retained `SetIsModal` call.
Simplified focus-setting logic in `ApplicationImpl.Run.cs` using
pattern matching for `TopRunnableView`.
In `Runnable<TResult>`, added `SetNeedsLayout` after `IsModalChanged`
to ensure layout updates. Removed an unused empty line for cleanup.
Corrected namespace in `GetViewsUnderLocationForRootTests.cs` to
align with test structure.
* Update layout on modal state change
A call to `SetNeedsLayout()` was added to the `OnIsModalChanged`
method in the `Runnable` class. This ensures that the layout
is updated whenever the modal state changes.
* Increase test timeout for inputTask.Wait to 10 seconds
Extended the timeout duration for the `inputTask.Wait` method
from 4 seconds to 10 seconds in `MainLoopCoordinatorTests`.
This change ensures the test has a longer window to complete
under conditions of increased load or slower execution
environments, reducing the likelihood of false test failures.
* Refactor project files and simplify test logic
Removed `<LangVersion>` and `<ImplicitUsings>` properties from
`UnitTests.csproj` and `UnitTests.Parallelizable.csproj` to rely
on default SDK settings and disable implicit global usings.
Simplified the `SizeChanged_Event_Still_Fires_For_Compatibility`
test in `FakeDriverTests` by removing the `screenChangedFired`
variable, its associated event handler, and related assertions.
Also removed obsolete warning suppression directives as they
are no longer needed.
* Reduce UnitTestsParallelizable iterations from 10 to 3
Reduced the number of iterations for the UnitTestsParallelizable
test suite from 10 to 3 to save time and resources while still
exposing concurrency issues. Updated the loop and log messages
to reflect the new iteration count.
* disabled InputLoop_Throttle_Limits_Poll_Rate
* Refactor app lifecycle and improve Runnable API
Refactored `Program.cs` to simplify application lifecycle:
- Modularized app creation, initialization, and disposal.
- Improved result handling and ensured proper resource cleanup.
Re-implemented `Runnable<TResult>` with a cleaner design:
- Retained functionality while improving readability and structure.
- Added XML documentation and followed the Cancellable Work Pattern.
Re-implemented `RunnableWrapper<TView, TResult>`:
- Enabled wrapping any `View` to make it runnable with typed results.
- Added examples and remarks for better developer guidance.
Re-implemented `ViewRunnableExtensions`:
- Provided fluent API for making views runnable with or without results.
- Enhanced documentation with examples for common use cases.
General improvements:
- Enhanced code readability, maintainability, and error handling.
- Replaced redundant code with cleaner, more maintainable versions.
* Modernize codebase for Terminal.Gui and MVVM updates
Refactored `LoginView` to remove redundant `Application.LayoutAndDraw()`
call. Enhanced `LoginViewModel` with new observable properties for
automatic property change notifications. Updated `Message` class to use
nullable generics for improved type safety.
Replaced legacy `Application.Init()` and `Application.Run()` calls with
the modern `IApplication` API across `Program.cs`, `Example.cs`, and
`ReactiveExample`. Ensured proper disposal of `IApplication` instances
to prevent resource leaks.
Updated `TerminalScheduler` to integrate with `IApplication` for
invoking actions and managing timeouts. Added null checks and improved
timeout disposal logic for robustness.
Refactored `ExampleWindow` for better readability and alignment with
modern `Terminal.Gui` conventions. Cleaned up unused imports and
improved code clarity across the codebase.
Updated README.md to reflect the latest `Terminal.Gui` practices,
including examples of the `IApplication` API and automatic UI refresh
handling. Renamed `LoginAction` to `LoginActions` for consistency.
* Refactor: Transition to IRunnable-based architecture
Replaced `Toplevel` with `Window` as the primary top-level UI element. Introduced the `IRunnable` interface to modernize the architecture, enabling greater flexibility and testability. Deprecated the static `Application` class in favor of the instance-based `IApplication` model, which supports multiple application contexts.
Updated methods like `Application.Run()` and `Application.RequestStop()` to use `IRunnable`. Removed or replaced legacy `Modal` properties with `IsModal`. Enhanced the `IApplication` interface with a fluent API, including methods like `Run<TRunnable>()` and `GetResult<T>()`.
Refactored tests and examples to align with the new architecture. Updated documentation to reflect the instance-based model. Deprecated obsolete members and methods, including `Application.Current` and `Application.TopRunnable`.
Improved event handling by replacing the `Accept` event with `Accepting` and using `e.Handled` for event processing. Updated threading examples to use `App?.Invoke()` or `app.Invoke()` for UI updates. Cleaned up redundant code and redefined modal behavior for better consistency.
These changes modernize the `Terminal.Gui` library, improving clarity, usability, and maintainability while ensuring backward compatibility where possible.
* Refactor: Replace Toplevel with Runnable class
This commit introduces a major architectural update to the `Terminal.Gui` library, replacing the legacy `Toplevel` class with the new `Runnable` class. The changes span the entire codebase, including core functionality, tests, documentation, and configuration files.
- **Core Class Replacement**:
- Replaced `Toplevel` with `Runnable` as the base class for modal views and session management.
- Updated all references to `Toplevel` in the codebase, including constructors, methods, and properties.
- **Configuration Updates**:
- Updated `tui-config-schema.json` to reflect the new `Runnable` scheme.
- **New Classes**:
- Added `UICatalogRunnable` for managing the UI Catalog application.
- Introduced `Runnable<TResult>` as a generic base class for blocking sessions with result handling.
- **Documentation and Tests**:
- Updated documentation to emphasize `Runnable` and mark `Toplevel` as obsolete.
- Refactored test cases to use `Runnable` and ensure compatibility.
- **Behavioral Improvements**:
- Enhanced lifecycle management and alignment with the `IRunnable` interface.
- Improved clarity and consistency in naming conventions.
These changes modernize the library, improve flexibility, and provide a clearer architecture for developers.
* Refactor: Consolidate Runnable classes and decouple View from ApplicationImpl
- Made Runnable<TResult> inherit from Runnable (eliminating ~180 LOC duplication)
- Moved View init/layout/cursor logic from ApplicationImpl to Runnable lifecycle events
- ApplicationImpl.Begin now operates purely on IRunnable interface
Related to #4419
* Simplified the disposal logic in `ApplicationImpl.Run.cs` by replacing
the type-specific check for `View` with a more general check for
`IDisposable`. This ensures proper disposal of any `IDisposable`
object, improving robustness.
Removed the `FrameworkOwnedRunnable` property from the `ApplicationImpl`
class in `ApplicationImpl.cs` and the `IApplication` interface in
`IApplication.cs`. This eliminates the need to manage this property,
reducing complexity and improving maintainability.
Updated `application.md` to reflect the removal of the
`FrameworkOwnedRunnable` property, ensuring the documentation aligns
with the updated codebase.
* Replaces the legacy `Shutdown()` method with `Dispose()` to align
with the `IDisposable` pattern, ensuring proper resource cleanup
and simplifying the API. The `Dispose()` method is now the
recommended way to release resources, with `using` statements
encouraged for automatic disposal.
Key changes:
- Marked `Shutdown()` as obsolete; it now internally calls `Dispose()`.
- Updated the fluent API to remove `Shutdown()` from chaining.
- Enhanced session lifecycle management for thread safety.
- Updated tests to validate proper disposal and state reset.
- Improved `IRunnable` integration with automatic disposal for
framework-created runnables.
- Maintained backward compatibility for the legacy static
`Application` singleton.
- Refactored documentation and examples to reflect modern practices
and emphasize `Dispose()` usage.
These changes modernize the `Terminal.Gui` lifecycle, improve
testability, and encourage alignment with .NET conventions.
* Refactor runnable app context handling in ApplicationImpl
Refactor how the application context is set for `runnable` objects
by introducing a new `SetApp` method in the `IRunnable` interface.
This replaces the previous logic of directly setting the `App`
property for `View` objects, making the process more generic and
encapsulated within `IRunnable` implementations.
Simplify `Mouse.UngrabMouse()` by removing the conditional check
and calling it unconditionally.
Make a minor formatting adjustment in the generic constraint of
`Run<TRunnable>` in `ApplicationImpl`.
Add `SetApp(IApplication app)` to the `IRunnable` interface and
implement it in the `Runnable` class to set the `App` property
to the provided application instance.
* Improve docs, tests, and modularity across the codebase
Reorganized and updated `CONTRIBUTING.md`:
- Added **Key Architecture Concepts** section and reordered the table of contents.
- Updated testing requirements to discourage legacy patterns.
- Added instructions for replicating CI workflows locally.
- Clarified PR guidelines and coding style expectations.
Enhanced `README.md` with detailed CI/CD workflow documentation.
Refactored `ColorPicker.Prompt` to use `IApplication` for improved modularity and testability.
Introduced `IApplicationScreenChangedTests` for comprehensive testing of `ScreenChanged` events and `Screen` property.
Refactored `ApplicationScreenTests` and `TextView.PromptForColors` to align with modern patterns.
Updated `Terminal.sln` to include `.github/workflows/README.md`.
Performed general cleanup:
- Removed outdated documentation links.
- Improved XML documentation and coding consistency.
* readme tweaks
* Improve thread safety, layout, and test coverage
Refactored `OutputBufferImpl.cs` to enhance thread safety by locking shared resources and adding bounds checks for columns and rows. Improved handling of wide characters and removed outdated TODO comments.
Updated `Runnable.cs` to call `SetNeedsDraw()` on modal state changes, ensuring proper layout and drawing updates. Simplified layout handling in `ApplicationImpl.Run.cs` by replacing redundant comments with a `LayoutAndDraw()` call.
Added a check in `AllViewsTester.cs` to skip creating instances of `RunnableWrapper` types with unsatisfiable generic constraints, logging a warning when encountered.
Enhanced `ListViewTests.cs` by adding explicit `app.LayoutAndDraw()` calls to validate visual output and ensure tests reflect the updated application state.
These changes improve robustness, prevent race conditions, and ensure consistent behavior across the application.
* Refactor: Rename Toplevel to Runnable and update logic
Updated the `Border` class to use `Command.Quit` instead of
`Command.QuitToplevel` in the `CloseButton.Accept` handler.
Renamed test methods in `GetViewsAtLocationTests.cs` to replace
"Toplevel" with "Runnable" for consistency. Updated `Runnable<bool>`
instances to use "topRunnable" as the `Id` property.
These changes align the codebase with updated naming conventions
and improve clarity.
* Removed `ToplevelTests` and migrated relevant test cases to
`MouseDragTests` with improved structure and coverage. Updated
tests to use `Application.Create`, `app.Begin`, and `app.End`
for better resource management and lifecycle handling.
Replaced direct event handling with `app.Mouse.RaiseMouseEvent`
to align with the application's event-handling mechanism. Added
`Runnable` objects to ensure views are properly initialized and
disposed of within the application context.
Enhanced tests to include assertions for minimum width and
height constraints during resize operations. Removed redundant
tests and streamlined logic to reduce duplication and improve
maintainability.
* Reorged Unit Test namespaces.
* more
* Refactor tests and update namespaces for consistency
Updated namespaces in `ArrangementTests.cs` and `MouseDragTests.cs` for better organization. Enhanced `ArrangementTests.cs` with additional checks for arrangement flags. Reformatted and re-added `MouseDragTests.cs` and `SchemeTests.cs` with modern C# features like nullable annotations and object initializers. Ensured no functional changes while improving code clarity and consistency.
* Fix nullability warnings in MouseDragTests.cs
Updated `app.End` calls to use the null-forgiving operator (`!`)
on `app.SessionStack` to ensure it is treated as non-null.
This change addresses potential nullability warnings and
improves code safety and clarity. Applied consistently across
all relevant test cases in the `MouseDragTests` class.
168 lines
9.7 KiB
Markdown
168 lines
9.7 KiB
Markdown
# Proposed Design for a modern Cursor system in v2
|
|
|
|
> [!IMPORTANT]
|
|
> This document is a work in progress and does not represent the final design or even the current implementation.
|
|
|
|
See end for list of issues this design addresses.
|
|
|
|
## Tenets for Cursor Support (Unless you know better ones...)
|
|
|
|
1. **More GUI than Command Line**. The concept of a cursor on the command line of a terminal is intrinsically tied to enabling the user to know where keyboard import is going to impact text editing. TUI apps have many more modalities than text editing where the keyboard is used (e.g. scrolling through a `ColorPicker`). Terminal.Gui's cursor system is biased towards the broader TUI experiences.
|
|
|
|
2. **Be Consistent With the User's Platform** - Users get to choose the platform they run *Terminal.Gui* apps on and the cursor should behave in a way consistent with the terminal.
|
|
|
|
## Lexicon & Taxonomy
|
|
|
|
- Navigation - Refers to the user-experience for moving Focus between views in the application view-hierarchy. See [Navigation](navigation.md) for a deep-dive.
|
|
- Focus - Indicates which View in the view-hierarchy is currently the one receiving keyboard input. Only one view-hexarchy in an application can have focus (`view.HasFocus == true`), and there is only one View in a focused hierarchy that is the most-focused; the one receiving keyboard input. See [Navigation](navigation.md) for a deep-dive.
|
|
- Cursor - A visual indicator to the user where keyboard input will have an impact. There is one Cursor per terminal session.
|
|
- Cursor Location - The top-left corner of the Cursor. In text entry scenarios, new text will be inserted to the left/top of the Cursor Location.
|
|
- Cursor Size - The width and height of the cursor. Currently the size is limited to 1x1.
|
|
- Cursor Style - How the cursor renders. Some terminals support various cursor styles such as Block and Underline.
|
|
- Cursor Visibility - Whether the cursor is visible to the user or not. NOTE: Some ConsoleDrivers overload Cursor Style and Cursor Visibility, making "invisible" a style. Terminal.Gui HIDES this from developers and changing the visibility of the cursor does NOT change the style.
|
|
- Caret - Visual indicator that where text entry will occur.
|
|
- Selection - A visual indicator to the user that something is selected. It is common for the Selection and Cursor to be the same. It is also common for the Selection and Cursor to be distinct. In a `ListView` the Cursor and Selection (`SelectedItem`) are the same, but the `Cursor` is not visible. In a `TextView` with text selected, the `Cursor` is at either the start or end of the `Selection`. A `TableView' supports mutliple things being selected at once.
|
|
|
|
## Requirements
|
|
|
|
- No flickering. The Cursor should blink/pulse at the rate dictated by the terminal. Typing, moving the mouse, view layout, etc... should not caue the cursor to flicker.
|
|
- By default, the Cursor should not be visible. A View or View subclass should have to do anything (this is already the case) to keep the Cursor invisible.
|
|
- Views that just want to show the cursor at a particular location in the Viewport should only have to:
|
|
- Optionally, declare a desired Cursor Style. Set `Application.CursorStyle`.
|
|
- Indicate the Cursor Locaiton when internal state dictates the location has changed (debatable if this should be in content or viewport-relative coords). Just set `this.CursorPosition`.
|
|
- To hide the cursor, simply set `this.CursorPostion` to `null`.
|
|
- The Cursor should only be visible in Views where
|
|
- `Enabled == true`
|
|
- `Visible == true`
|
|
- `CanFocus == true`
|
|
- `this == SuperView.MostFocused`
|
|
- If a `ConsoleDriver` supports Cursor Styles other than Default, they should be supported per-application (NOT View).
|
|
- Ensuring the cursor is visible or not should be handled by `Application`, not `View`.
|
|
- General V2 Requirement: View sub-class code should NEVER call a `Driver.` API. Only `Application` and the `View` base class should call `ConsoleDriver` APIs; before we ship v2, all `ConsoleDriver` APIs will be made `internal`.
|
|
|
|
## Design
|
|
|
|
### `View` Focus Changes
|
|
|
|
It doesn't make sense the every View instance has it's own notion of `MostFocused`. The current implemention is overly complicated and fragile because the concept of "MostFocused" is handled by `View`. There can be only ONE "most focused" view in an application. `MostFocused` should be a property on `Application`.
|
|
|
|
* Remove `View.MostFocused`
|
|
* Change all references to access `Application.MostFocusedView` (see `Application` below)
|
|
* Find all instances of `view._hasFocus = ` and change them to use `SetHasFocus` (today, anyplace that sets `_hasFocus` is a BUG!!).
|
|
* Change `SetFocus`/`SetHasFocus` etc... such that if the focus is changed to a different view heirarchy, `Application.MostFocusedView` gets set appropriately.
|
|
|
|
**MORE THOUGHT REQUIRED HERE** - There be dragons given how `Runnable` has `OnEnter/OnLeave` overrrides. The above needs more study, but is directioally correct.
|
|
|
|
### `View` Cursor Changes
|
|
* Add `public Point? CursorPosition`
|
|
- Backed with `private Point? _cursorPosition`
|
|
- If `!HasValue` the cursor is not visible
|
|
- If `HasValue` the cursor is visible at the Point.
|
|
- On set, if `value != _cursorPosition`, call `OnCursorPositionChanged()`
|
|
* Add `public event EventHandler<LocaitonChangedEventArgs>? CursorPositionChanged`
|
|
* Add `internal void OnCursorPositionChanged(LocationChangedEventArgs a)`
|
|
* Not virtual
|
|
* Fires `CursorPositionChanged`
|
|
|
|
### `ConsoleDriver`s
|
|
|
|
* Remove `Refresh` and have `UpdateScreen` and `UpdateCursor` be called separately. The fact that `Refresh` in all drivers currently calls both is a source of flicker.
|
|
|
|
* Remove the `xxxCursorVisibility` APIs and replace with:
|
|
* `internal int CursorStyle {get; internal set; }`
|
|
- Backed with `private int _cursorStyle`
|
|
- On set, calls `OnCursorStyleChanged()`
|
|
* Add `internal abstract void OnCursorStyleChanged()`
|
|
- Called by `base` whenever the cursor style changes, but ONLY if `value != _cursorStyle`.
|
|
|
|
* Add `internal virtual (int Id, string StyleName) [] GetCursorStyles()`
|
|
- Returns an array of styles supported by the driver, NOT including Invisible.
|
|
- The first item in array is always "Default".
|
|
- Base implementation returns `{ 0, "Default" }`
|
|
- `CursesDriver` and `WindowsDriver` will need to implement overrides.
|
|
|
|
* Add `internal Point? CursorPosition {get; internal set; }`
|
|
- Backed with `private Point? _cursorPosition`
|
|
- If `!HasValue` the cursor is not visible
|
|
- If `HasValue` the cursor is visible at the Point.
|
|
- On set, calls `OnCursorPositionChanged` ONLY if `value != _cursorPosition`.
|
|
* Add `internal abstract void OnCursorPositionChanged()`
|
|
- Called by `base` whenever the cursor position changes.
|
|
- Depending on the value of `CursorPosition`:
|
|
- If `!HasValue` the cursor is not visible - does whatever is needed to make the cursor invisible.
|
|
- If `HasValue` the cursor is visible at the `CursorPosition` - does whatever is needed to make the cursor visible (using `CursorStyle`).
|
|
|
|
* Make sure the drivers only make the cursor visible (or leave it visible) when `CursorPosition` changes!
|
|
|
|
### `Application`
|
|
|
|
*
|
|
|
|
* Add `internal static View FocusedView {get; private set;}`
|
|
- Backed by `private static _focusedView`
|
|
- On set,
|
|
- if `value != _focusedView`
|
|
- Unsubscribe from `_focusedView.CursorPositionChanged`
|
|
- Subscribe to `value.CursorPositionChanged += CursorPositionChanged`
|
|
- `_focusedView = value`
|
|
- Call `UpdateCursor`
|
|
|
|
* Add `internal bool CursorPositionChanged (object sender, LocationChangedEventArgs a)`
|
|
|
|
Called when:
|
|
|
|
- `FocusedView`
|
|
- Has changed to another View (should cover `FocusedView.Visible/Enable` changes)
|
|
- Has changed layout -
|
|
- Has changeed it's `CursorPosition`
|
|
- `CursorStyle` has changed
|
|
|
|
Does:
|
|
|
|
- If `FocusedView is {}` and `FocusedView.CursorPosition` is visible (e.g. w/in `FocusedView.SuperView.Viewport`)
|
|
- Does `Driver.CursorPosition = ToScreen(FocusedView.CursorPosition)`
|
|
- Else
|
|
- Makes driver cursor invisible with `Driver.CursorPosition = null`
|
|
|
|
* Add `public static int CursorStyle {get; internal set; }`
|
|
- Backed with `private static int _cursorStyle
|
|
- If `value != _cursorStyle`
|
|
- Calls `ConsoleDriver.CursorStyle = _cursorStyle`
|
|
- Calls `UpdateCursor`
|
|
|
|
* Add `public (int Id, string StyleName) [] GetCursorStyles()`
|
|
- Calls through to `ConsoleDriver.GetCursorStyles()`
|
|
|
|
|
|
|
|
# Issues with Current Design
|
|
|
|
## `Driver.Row/Pos`, which are changed via `Move` serves two purposes that confuse each other:
|
|
|
|
a) Where the next `AddRune` will put the next rune
|
|
b) The current "Cursor Location"
|
|
|
|
If most TUI apps acted like a command line where the visible cursor was always visible, this might make sense. But the fact that only a very few View subclasses we've seen actually care to show the cursor illustrates a problem:
|
|
|
|
Any drawing causes the "Cursor Position" to be changed/lost. This means we have a ton of code that is constantly repositioning the cursor every MainLoop iteration.
|
|
|
|
## The actual cursor position RARELY changes (relative to `Mainloop.Iteration`).
|
|
|
|
Derived from abo`ve, the current design means we need to call `View.PositionCursor` every iteration. For some views this is a low-cost operation. For others it involves a lot of math.
|
|
|
|
This is just stupid.
|
|
|
|
## Flicker
|
|
|
|
Related to the above, we need constantly Show/Hide the cursor every iteration. This causes ridiculous cursor flicker.
|
|
|
|
## `View.PositionCursor` is poorly spec'd and confusing to implement correctly
|
|
|
|
Should a view call `base.PositionCursor`? If so, before or after doing stuff?
|
|
|
|
## Setting cursor visibility in `OnEnter` actually makes no sense
|
|
|
|
First, leaving it up to views to do this is fragile.
|
|
|
|
Second, when a View gets focus is but one of many places where cursor visibilty should be updated.
|