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Terminal.Gui/Terminal.Gui/Core/Application.cs
Charlie Kindel 8730ac6f37 first unit tests
2020-06-07 21:44:03 -06:00

708 lines
21 KiB
C#

//
// Core.cs: The core engine for gui.cs
//
// Authors:
// Miguel de Icaza (miguel@gnome.org)
//
// Pending:
// - Check for NeedDisplay on the hierarchy and repaint
// - Layout support
// - "Colors" type or "Attributes" type?
// - What to surface as "BackgroundCOlor" when clearing a window, an attribute or colors?
//
// Optimziations
// - Add rendering limitation to the exposed area
using System;
using System.Collections;
using System.Collections.Generic;
using System.Threading;
using System.Linq;
using NStack;
using System.ComponentModel;
namespace Terminal.Gui {
/// <summary>
/// A static, singelton class provding the main application driver for Terminal.Gui apps.
/// </summary>
/// <example>
/// <code>
/// // A simple Terminal.Gui app that creates a window with a frame and title with
/// // 5 rows/columns of padding.
/// Application.Init();
/// var win = new Window ("Hello World - CTRL-Q to quit") {
/// X = 5,
/// Y = 5,
/// Width = Dim.Fill (5),
/// Height = Dim.Fill (5)
/// };
/// Application.Top.Add(win);
/// Application.Run();
/// </code>
/// </example>
/// <remarks>
/// <para>
/// Creates a instance of <see cref="Terminal.Gui.MainLoop"/> to process input events, handle timers and
/// other sources of data. It is accessible via the <see cref="MainLoop"/> property.
/// </para>
/// <para>
/// You can hook up to the <see cref="Iteration"/> event to have your method
/// invoked on each iteration of the <see cref="Terminal.Gui.MainLoop"/>.
/// </para>
/// <para>
/// When invoked sets the SynchronizationContext to one that is tied
/// to the mainloop, allowing user code to use async/await.
/// </para>
/// </remarks>
public static class Application {
/// <summary>
/// The current <see cref="ConsoleDriver"/> in use.
/// </summary>
public static ConsoleDriver Driver;
/// <summary>
/// The <see cref="Toplevel"/> object used for the application on startup (<seealso cref="Application.Top"/>)
/// </summary>
/// <value>The top.</value>
public static Toplevel Top { get; private set; }
/// <summary>
/// The current <see cref="Toplevel"/> object. This is updated when <see cref="Application.Run()"/> enters and leaves to point to the current <see cref="Toplevel"/> .
/// </summary>
/// <value>The current.</value>
public static Toplevel Current { get; private set; }
/// <summary>
/// TThe current <see cref="View"/> object being redrawn.
/// </summary>
/// /// <value>The current.</value>
public static View CurrentView { get; set; }
/// <summary>
/// The <see cref="MainLoop"/> driver for the applicaiton
/// </summary>
/// <value>The main loop.</value>
public static MainLoop MainLoop { get; private set; }
static Stack<Toplevel> toplevels = new Stack<Toplevel> ();
/// <summary>
/// This event is raised on each iteration of the <see cref="MainLoop"/>
/// </summary>
/// <remarks>
/// See also <see cref="Timeout"/>
/// </remarks>
public static Action Iteration;
/// <summary>
/// Returns a rectangle that is centered in the screen for the provided size.
/// </summary>
/// <returns>The centered rect.</returns>
/// <param name="size">Size for the rectangle.</param>
public static Rect MakeCenteredRect (Size size)
{
return new Rect (new Point ((Driver.Cols - size.Width) / 2, (Driver.Rows - size.Height) / 2), size);
}
//
// provides the sync context set while executing code in Terminal.Gui, to let
// users use async/await on their code
//
class MainLoopSyncContext : SynchronizationContext {
MainLoop mainLoop;
public MainLoopSyncContext (MainLoop mainLoop)
{
this.mainLoop = mainLoop;
}
public override SynchronizationContext CreateCopy ()
{
return new MainLoopSyncContext (MainLoop);
}
public override void Post (SendOrPostCallback d, object state)
{
mainLoop.AddIdle (() => {
d (state);
return false;
});
//mainLoop.Driver.Wakeup ();
}
public override void Send (SendOrPostCallback d, object state)
{
mainLoop.Invoke (() => {
d (state);
});
}
}
/// <summary>
/// If set, it forces the use of the System.Console-based driver.
/// </summary>
public static bool UseSystemConsole;
/// <summary>
/// Initializes a new instance of <see cref="Terminal.Gui"/> Application.
/// </summary>
/// <remarks>
/// <para>
/// Call this method once per instance (or after <see cref="Shutdown"/> has been called).
/// </para>
/// <para>
/// Loads the right <see cref="ConsoleDriver"/> for the platform.
/// </para>
/// <para>
/// Creates a <see cref="Toplevel"/> and assigns it to <see cref="Top"/> and <see cref="CurrentView"/>
/// </para>
/// </remarks>
public static void Init (ConsoleDriver driver = null) => Init (() => Toplevel.Create (), driver);
internal static bool _initialized = false;
/// <summary>
/// Initializes the Terminal.Gui application
/// </summary>
static void Init (Func<Toplevel> topLevelFactory, ConsoleDriver driver = null)
{
if (_initialized) return;
// This supports Unit Tests and the passing of a mock driver/loopdriver
if (driver != null) {
Driver = driver;
Driver.Init (TerminalResized);
MainLoop = new MainLoop ((IMainLoopDriver)driver);
SynchronizationContext.SetSynchronizationContext (new MainLoopSyncContext (MainLoop));
}
if (Driver == null) {
var p = Environment.OSVersion.Platform;
IMainLoopDriver mainLoopDriver;
if (UseSystemConsole) {
mainLoopDriver = new NetMainLoop ();
Driver = new NetDriver ();
} else if (p == PlatformID.Win32NT || p == PlatformID.Win32S || p == PlatformID.Win32Windows) {
var windowsDriver = new WindowsDriver ();
mainLoopDriver = windowsDriver;
Driver = windowsDriver;
} else {
mainLoopDriver = new UnixMainLoop ();
Driver = new CursesDriver ();
}
Driver.Init (TerminalResized);
MainLoop = new MainLoop (mainLoopDriver);
SynchronizationContext.SetSynchronizationContext (new MainLoopSyncContext (MainLoop));
}
Top = topLevelFactory ();
Current = Top;
CurrentView = Top;
_initialized = true;
}
/// <summary>
/// Captures the execution state for the provided <see cref="Toplevel"/> view.
/// </summary>
public class RunState : IDisposable {
internal bool closeDriver = true;
/// <summary>
/// Initializes a new <see cref="RunState"/> class.
/// </summary>
/// <param name="view"></param>
public RunState (Toplevel view)
{
Toplevel = view;
}
internal Toplevel Toplevel;
/// <summary>
/// Releases alTop = l resource used by the <see cref="Application.RunState"/> object.
/// </summary>
/// <remarks>Call <see cref="Dispose()"/> when you are finished using the <see cref="Application.RunState"/>. The
/// <see cref="Dispose()"/> method leaves the <see cref="Application.RunState"/> in an unusable state. After
/// calling <see cref="Dispose()"/>, you must release all references to the
/// <see cref="Application.RunState"/> so the garbage collector can reclaim the memory that the
/// <see cref="Application.RunState"/> was occupying.</remarks>
public void Dispose ()
{
Dispose (closeDriver);
GC.SuppressFinalize (this);
}
/// <summary>
/// Dispose the specified disposing.
/// </summary>
/// <returns>The dispose.</returns>
/// <param name="disposing">If set to <c>true</c> disposing.</param>
protected virtual void Dispose (bool disposing)
{
if (Toplevel != null) {
End (Toplevel, disposing);
Toplevel = null;
}
}
}
static void ProcessKeyEvent (KeyEvent ke)
{
var chain = toplevels.ToList ();
foreach (var topLevel in chain) {
if (topLevel.ProcessHotKey (ke))
return;
if (topLevel.Modal)
break;
}
foreach (var topLevel in chain) {
if (topLevel.ProcessKey (ke))
return;
if (topLevel.Modal)
break;
}
foreach (var topLevel in chain) {
// Process the key normally
if (topLevel.ProcessColdKey (ke))
return;
if (topLevel.Modal)
break;
}
}
static void ProcessKeyDownEvent (KeyEvent ke)
{
var chain = toplevels.ToList ();
foreach (var topLevel in chain) {
if (topLevel.OnKeyDown (ke))
return;
if (topLevel.Modal)
break;
}
}
static void ProcessKeyUpEvent (KeyEvent ke)
{
var chain = toplevels.ToList ();
foreach (var topLevel in chain) {
if (topLevel.OnKeyUp (ke))
return;
if (topLevel.Modal)
break;
}
}
static View FindDeepestView (View start, int x, int y, out int resx, out int resy)
{
var startFrame = start.Frame;
if (!startFrame.Contains (x, y)) {
resx = 0;
resy = 0;
return null;
}
if (start.InternalSubviews != null) {
int count = start.InternalSubviews.Count;
if (count > 0) {
var rx = x - startFrame.X;
var ry = y - startFrame.Y;
for (int i = count - 1; i >= 0; i--) {
View v = start.InternalSubviews [i];
if (v.Frame.Contains (rx, ry)) {
var deep = FindDeepestView (v, rx, ry, out resx, out resy);
if (deep == null)
return v;
return deep;
}
}
}
}
resx = x - startFrame.X;
resy = y - startFrame.Y;
return start;
}
internal static View mouseGrabView;
/// <summary>
/// Grabs the mouse, forcing all mouse events to be routed to the specified view until UngrabMouse is called.
/// </summary>
/// <returns>The grab.</returns>
/// <param name="view">View that will receive all mouse events until UngrabMouse is invoked.</param>
public static void GrabMouse (View view)
{
if (view == null)
return;
mouseGrabView = view;
Driver.UncookMouse ();
}
/// <summary>
/// Releases the mouse grab, so mouse events will be routed to the view on which the mouse is.
/// </summary>
public static void UngrabMouse ()
{
mouseGrabView = null;
Driver.CookMouse ();
}
/// <summary>
/// Merely a debugging aid to see the raw mouse events
/// </summary>
public static Action<MouseEvent> RootMouseEvent;
internal static View wantContinuousButtonPressedView;
static View lastMouseOwnerView;
static void ProcessMouseEvent (MouseEvent me)
{
var view = FindDeepestView (Current, me.X, me.Y, out int rx, out int ry);
if (view != null && view.WantContinuousButtonPressed)
wantContinuousButtonPressedView = view;
else
wantContinuousButtonPressedView = null;
RootMouseEvent?.Invoke (me);
if (mouseGrabView != null) {
var newxy = mouseGrabView.ScreenToView (me.X, me.Y);
var nme = new MouseEvent () {
X = newxy.X,
Y = newxy.Y,
Flags = me.Flags,
OfX = me.X - newxy.X,
OfY = me.Y - newxy.Y,
View = view
};
if (OutsideFrame (new Point (nme.X, nme.Y), mouseGrabView.Frame)) {
lastMouseOwnerView?.OnMouseLeave (me);
}
if (mouseGrabView != null) {
mouseGrabView.OnMouseEvent (nme);
return;
}
}
if (view != null) {
var nme = new MouseEvent () {
X = rx,
Y = ry,
Flags = me.Flags,
OfX = rx,
OfY = ry,
View = view
};
if (lastMouseOwnerView == null) {
lastMouseOwnerView = view;
view.OnMouseEnter (nme);
} else if (lastMouseOwnerView != view) {
lastMouseOwnerView.OnMouseLeave (nme);
view.OnMouseEnter (nme);
lastMouseOwnerView = view;
}
if (!view.WantMousePositionReports && me.Flags == MouseFlags.ReportMousePosition)
return;
if (view.WantContinuousButtonPressed)
wantContinuousButtonPressedView = view;
else
wantContinuousButtonPressedView = null;
// Should we bubbled up the event, if it is not handled?
view.OnMouseEvent (nme);
}
}
static bool OutsideFrame (Point p, Rect r)
{
return p.X < 0 || p.X > r.Width - 1 || p.Y < 0 || p.Y > r.Height - 1;
}
/// <summary>
/// This event is fired once when the application is first loaded. The dimensions of the
/// terminal are provided.
/// </summary>
public static Action<ResizedEventArgs> Loaded;
/// <summary>
/// Building block API: Prepares the provided <see cref="Toplevel"/> for execution.
/// </summary>
/// <returns>The runstate handle that needs to be passed to the <see cref="End(RunState, bool)"/> method upon completion.</returns>
/// <param name="toplevel">Toplevel to prepare execution for.</param>
/// <remarks>
/// This method prepares the provided toplevel for running with the focus,
/// it adds this to the list of toplevels, sets up the mainloop to process the
/// event, lays out the subviews, focuses the first element, and draws the
/// toplevel in the screen. This is usually followed by executing
/// the <see cref="RunLoop"/> method, and then the <see cref="End(RunState, bool)"/> method upon termination which will
/// undo these changes.
/// </remarks>
public static RunState Begin (Toplevel toplevel)
{
if (toplevel == null)
throw new ArgumentNullException (nameof (toplevel));
var rs = new RunState (toplevel);
Init ();
if (toplevel is ISupportInitializeNotification initializableNotification &&
!initializableNotification.IsInitialized) {
initializableNotification.BeginInit ();
initializableNotification.EndInit ();
} else if (toplevel is ISupportInitialize initializable) {
initializable.BeginInit ();
initializable.EndInit ();
}
toplevels.Push (toplevel);
Current = toplevel;
Driver.PrepareToRun (MainLoop, ProcessKeyEvent, ProcessKeyDownEvent, ProcessKeyUpEvent, ProcessMouseEvent);
if (toplevel.LayoutStyle == LayoutStyle.Computed)
toplevel.SetRelativeLayout (new Rect (0, 0, Driver.Cols, Driver.Rows));
toplevel.LayoutSubviews ();
Loaded?.Invoke (new ResizedEventArgs () { Rows = Driver.Rows, Cols = Driver.Cols });
toplevel.WillPresent ();
Redraw (toplevel);
toplevel.PositionCursor ();
Driver.Refresh ();
return rs;
}
/// <summary>
/// Building block API: completes the execution of a <see cref="Toplevel"/> that was started with <see cref="Begin(Toplevel)"/> .
/// </summary>
/// <param name="runState">The runstate returned by the <see cref="Begin(Toplevel)"/> method.</param>
/// <param name="closeDriver"><c>true</c>Closes the application.<c>false</c>Closes the toplevels only.</param>
public static void End (RunState runState, bool closeDriver = true)
{
if (runState == null)
throw new ArgumentNullException (nameof (runState));
runState.closeDriver = closeDriver;
runState.Dispose ();
}
/// <summary>
/// Shutdown an application initialized with <see cref="Init(ConsoleDriver)"/>
/// </summary>
/// /// <param name="closeDriver"><c>true</c>Closes the application.<c>false</c>Closes toplevels only.</param>
public static void Shutdown (bool closeDriver = true)
{
// Shutdown is the bookend for Init. As such it needs to clean up all resources
// Init created. Apps that do any threading will need to code defensively for this.
// e.g. see Issue #537
// TODO: Some of this state is actually related to Begin/End (not Init/Shutdown) and should be moved to `RunState` (#520)
foreach (var t in toplevels) {
t.Running = false;
}
toplevels.Clear ();
Current = null;
CurrentView = null;
Top = null;
// Closes the application if it's true.
if (closeDriver) {
MainLoop = null;
Driver?.End ();
Driver = null;
}
_initialized = false;
}
static void Redraw (View view)
{
Application.CurrentView = view;
view.Redraw (view.Bounds);
Driver.Refresh ();
}
static void Refresh (View view)
{
view.Redraw (view.Bounds);
Driver.Refresh ();
}
/// <summary>
/// Triggers a refresh of the entire display.
/// </summary>
public static void Refresh ()
{
Driver.UpdateScreen ();
View last = null;
foreach (var v in toplevels.Reverse ()) {
v.SetNeedsDisplay ();
v.Redraw (v.Bounds);
last = v;
}
last?.PositionCursor ();
Driver.Refresh ();
}
internal static void End (View view, bool closeDriver = true)
{
if (toplevels.Peek () != view)
throw new ArgumentException ("The view that you end with must be balanced");
toplevels.Pop ();
if (toplevels.Count == 0)
Shutdown (closeDriver);
else {
Current = toplevels.Peek ();
Refresh ();
}
}
/// <summary>
/// Building block API: Runs the main loop for the created dialog
/// </summary>
/// <remarks>
/// Use the wait parameter to control whether this is a
/// blocking or non-blocking call.
/// </remarks>
/// <param name="state">The state returned by the Begin method.</param>
/// <param name="wait">By default this is true which will execute the runloop waiting for events, if you pass false, you can use this method to run a single iteration of the events.</param>
public static void RunLoop (RunState state, bool wait = true)
{
if (state == null)
throw new ArgumentNullException (nameof (state));
if (state.Toplevel == null)
throw new ObjectDisposedException ("state");
bool firstIteration = true;
for (state.Toplevel.Running = true; state.Toplevel.Running;) {
if (MainLoop.EventsPending (wait)) {
// Notify Toplevel it's ready
if (firstIteration) {
state.Toplevel.OnReady ();
}
firstIteration = false;
MainLoop.MainIteration ();
Iteration?.Invoke ();
} else if (wait == false)
return;
if (state.Toplevel.NeedDisplay != null && (!state.Toplevel.NeedDisplay.IsEmpty || state.Toplevel.childNeedsDisplay)) {
state.Toplevel.Redraw (state.Toplevel.Bounds);
if (DebugDrawBounds)
DrawBounds (state.Toplevel);
state.Toplevel.PositionCursor ();
Driver.Refresh ();
} else
Driver.UpdateCursor ();
}
}
internal static bool DebugDrawBounds = false;
// Need to look into why this does not work properly.
static void DrawBounds (View v)
{
v.DrawFrame (v.Frame, padding: 0, fill: false);
if (v.InternalSubviews != null && v.InternalSubviews.Count > 0)
foreach (var sub in v.InternalSubviews)
DrawBounds (sub);
}
/// <summary>
/// Runs the application by calling <see cref="Run(Toplevel, bool)"/> with the value of <see cref="Top"/>
/// </summary>
public static void Run ()
{
Run (Top);
}
/// <summary>
/// Runs the application by calling <see cref="Run(Toplevel, bool)"/> with a new instance of the specified <see cref="Toplevel"/>-derived class
/// </summary>
public static void Run<T> () where T : Toplevel, new()
{
Init (() => new T ());
Run (Top);
}
/// <summary>
/// Runs the main loop on the given <see cref="Toplevel"/> container.
/// </summary>
/// <remarks>
/// <para>
/// This method is used to start processing events
/// for the main application, but it is also used to
/// run other modal <see cref="View"/>s such as <see cref="Dialog"/> boxes.
/// </para>
/// <para>
/// To make a <see cref="Run(Toplevel, bool)"/> stop execution, call <see cref="Application.RequestStop"/>.
/// </para>
/// <para>
/// Calling <see cref="Run(Toplevel, bool)"/> is equivalent to calling <see cref="Begin(Toplevel)"/>, followed by <see cref="RunLoop(RunState, bool)"/>,
/// and then calling <see cref="End(RunState, bool)"/>.
/// </para>
/// <para>
/// Alternatively, to have a program control the main loop and
/// process events manually, call <see cref="Begin(Toplevel)"/> to set things up manually and then
/// repeatedly call <see cref="RunLoop(RunState, bool)"/> with the wait parameter set to false. By doing this
/// the <see cref="RunLoop(RunState, bool)"/> method will only process any pending events, timers, idle handlers and
/// then return control immediately.
/// </para>
/// </remarks>
public static void Run (Toplevel view, bool closeDriver = true)
{
var runToken = Begin (view);
RunLoop (runToken);
End (runToken, closeDriver);
}
/// <summary>
/// Stops running the most recent <see cref="Toplevel"/>.
/// </summary>
/// <remarks>
/// <para>
/// This will cause <see cref="Application.Run()"/> to return.
/// </para>
/// <para>
/// Calling <see cref="Application.RequestStop"/> is equivalent to setting the <see cref="Toplevel.Running"/> property on the curently running <see cref="Toplevel"/> to false.
/// </para>
/// </remarks>
public static void RequestStop ()
{
Current.Running = false;
}
/// <summary>
/// Event arguments for the <see cref="Application.Resized"/> event.
/// </summary>
public class ResizedEventArgs : EventArgs {
/// <summary>
/// The number of rows in the resized terminal.
/// </summary>
public int Rows { get; set; }
/// <summary>
/// The number of columns in the resized terminal.
/// </summary>
public int Cols { get; set; }
}
/// <summary>
/// Invoked when the terminal was resized. The new size of the terminal is provided.
/// </summary>
public static Action<ResizedEventArgs> Resized;
static void TerminalResized ()
{
var full = new Rect (0, 0, Driver.Cols, Driver.Rows);
Resized?.Invoke (new ResizedEventArgs () { Cols = full.Width, Rows = full.Height });
Driver.Clip = full;
foreach (var t in toplevels) {
t.PositionToplevels ();
t.SetRelativeLayout (full);
t.LayoutSubviews ();
}
Refresh ();
}
}
}