Para una vista construida con WPF, quiero cambiar el cursor del mouse a un reloj de arena cuando la aplicación está ocupada y no responde.
Una solución es agregar
this.Cursor = Cursors.Wait;a todos los lugares que pueden hacer que la interfaz de usuario deje de responder. Pero, obviamente, esta no es la mejor solución. Me pregunto cuál es la mejor manera de lograrlo.
¿Es posible lograr esto usando estilos o recursos?
Gracias,
Respuestas:
Hicimos una clase desechable que cambia el cursor por nosotros cuando la aplicación va a tardar mucho, se ve así:
public class WaitCursor : IDisposable
{
private Cursor _previousCursor;
public WaitCursor()
{
_previousCursor = Mouse.OverrideCursor;
Mouse.OverrideCursor = Cursors.Wait;
}
#region IDisposable Members
public void Dispose()
{
Mouse.OverrideCursor = _previousCursor;
}
#endregion
}
Y lo usamos así:
using(new WaitCursor())
{
// very long task
}
Puede que no sea el mejor diseño, pero funciona =)
using(uiServices.ShowWaitCursor()). Parece engorroso pero facilita las pruebas unitarias.
Usé las respuestas aquí para construir algo que funcionó mejor para mí. El problema es que cuando finaliza el bloque de uso en la respuesta de Carlo, es posible que la interfaz de usuario todavía esté ocupada vinculando datos. Es posible que se activen eventos o datos de carga diferida como resultado de lo que se hizo en el bloque. En mi caso, a veces pasaron varios segundos desde que el cursor de espera desapareció hasta que la interfaz de usuario estuvo realmente lista. Lo resolví creando un método de ayuda que configura el cursor de espera y también se encarga de configurar un temporizador que automáticamente restablecerá el cursor cuando la interfaz de usuario esté lista. No puedo estar seguro de que este diseño funcione en todos los casos, pero funcionó para mí:
/// <summary>
/// Contains helper methods for UI, so far just one for showing a waitcursor
/// </summary>
public static class UiServices
{
/// <summary>
/// A value indicating whether the UI is currently busy
/// </summary>
private static bool IsBusy;
/// <summary>
/// Sets the busystate as busy.
/// </summary>
public static void SetBusyState()
{
SetBusyState(true);
}
/// <summary>
/// Sets the busystate to busy or not busy.
/// </summary>
/// <param name="busy">if set to <c>true</c> the application is now busy.</param>
private static void SetBusyState(bool busy)
{
if (busy != IsBusy)
{
IsBusy = busy;
Mouse.OverrideCursor = busy ? Cursors.Wait : null;
if (IsBusy)
{
new DispatcherTimer(TimeSpan.FromSeconds(0), DispatcherPriority.ApplicationIdle, dispatcherTimer_Tick, Application.Current.Dispatcher);
}
}
}
/// <summary>
/// Handles the Tick event of the dispatcherTimer control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
private static void dispatcherTimer_Tick(object sender, EventArgs e)
{
var dispatcherTimer = sender as DispatcherTimer;
if (dispatcherTimer != null)
{
SetBusyState(false);
dispatcherTimer.Stop();
}
}
}
Simplemente estoy haciendo
Mouse.OverrideCursor = Cursors.Wait;
try {
// Long lasting stuff ...
} finally {
Mouse.OverrideCursor = null;
}
De acuerdo con la documentación de Mouse.OverrideCursor Property
Para borrar el cursor de anulación, establezca OverrideCursor en nulo.
La instrucción try-finalmente asegura que el cursor predeterminado se restaure en cualquier caso, incluso cuando ocurre una excepción o la parte try se deja con returno break(si está dentro de un bucle).
La mejor manera sería no hacer que la interfaz de usuario no responda nunca, descargando todo el trabajo a otros subprocesos / tareas según corresponda.
Aparte de eso, estás en un catch-22: si agregaste una forma de detectar que la interfaz de usuario no responde, no hay una buena manera de cambiar el cursor, ya que el lugar donde necesitarías hacer eso ( el hilo par) no responde ... ¿Sin embargo, es posible que pueda invocar el código win32 estándar para cambiar el cursor para toda la ventana?
De lo contrario, tendría que hacerlo de forma preventiva, como sugiere su pregunta.
Personalmente prefiero no ver que el puntero del mouse cambia muchas veces de reloj de arena a flecha. Para ayudar a prevenir ese comportamiento al llamar a funciones incrustadas que toman un tiempo y cada una intenta controlar el puntero del mouse, utilizo una pila (contador) que llamo LifeTrackerStack. Y solo cuando la pila está vacía (contador a 0) que coloco el reloj de arena en una flecha.
También uso MVVM. También prefiero el código seguro para subprocesos.
En mi clase raíz de modelo, declaro mi LifeTrackerStack que pueblo en clases de modelo para niños o lo uso directamente desde clases de modelos para niños cuando tengo acceso a él desde ellas.
Mi rastreador de vida tiene 2 estados / acciones:
Luego, en mi opinión, me vinculo manualmente a mi Model.IsBusy y hago:
void ModelPropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
{
if (e.PropertyName == "IsBusy")
{
if (this._modelViewAnalysis.IsBusy)
{
if (Application.Current.Dispatcher.CheckAccess())
{
this.Cursor = Cursors.Wait;
}
else
{
Application.Current.Dispatcher.Invoke(new Action(() => this.Cursor = Cursors.Wait));
}
}
else
{
Application.Current.Dispatcher.Invoke(new Action(() => this.Cursor = null));
}
}
Esta es mi clase LifeTrackerStack:
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading;
namespace HQ.Util.General
{
/// <summary>
/// Usage is to have only one event for a recursive call on many objects
/// </summary>
public class LifeTrackerStack
{
// ******************************************************************
protected readonly Action _stackCreationAction;
protected readonly Action _stackDisposeAction;
private int _refCount = 0;
private object _objLock = new object();
// ******************************************************************
public LifeTrackerStack(Action stackCreationAction = null, Action stackDisposeAction = null)
{
_stackCreationAction = stackCreationAction;
_stackDisposeAction = stackDisposeAction;
}
// ******************************************************************
/// <summary>
/// Return a new LifeTracker to be used in a 'using' block in order to ensure reliability
/// </summary>
/// <returns></returns>
public LifeTracker GetNewLifeTracker()
{
LifeTracker lifeTracker = new LifeTracker(AddRef, RemoveRef);
return lifeTracker;
}
// ******************************************************************
public int Count
{
get { return _refCount; }
}
// ******************************************************************
public void Reset()
{
lock (_objLock)
{
_refCount = 0;
if (_stackDisposeAction != null)
{
_stackDisposeAction();
}
}
}
// ******************************************************************
private void AddRef()
{
lock (_objLock)
{
if (_refCount == 0)
{
if (_stackCreationAction != null)
{
_stackCreationAction();
}
}
_refCount++;
}
}
// ******************************************************************
private void RemoveRef()
{
bool shouldDispose = false;
lock (_objLock)
{
if (_refCount > 0)
{
_refCount--;
}
if (_refCount == 0)
{
if (_stackDisposeAction != null)
{
_stackDisposeAction();
}
}
}
}
// ******************************************************************
}
}
using System;
namespace HQ.Util.General
{
public delegate void ActionDelegate();
public class LifeTracker : IDisposable
{
private readonly ActionDelegate _actionDispose;
public LifeTracker(ActionDelegate actionCreation, ActionDelegate actionDispose)
{
_actionDispose = actionDispose;
if (actionCreation != null)
actionCreation();
}
private bool _disposed = false;
public void Dispose()
{
Dispose(true);
// This object will be cleaned up by the Dispose method.
// Therefore, you should call GC.SupressFinalize to
// take this object off the finalization queue
// and prevent finalization code for this object
// from executing a second time.
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
// Check to see if Dispose has already been called.
if (!this._disposed)
{
// If disposing equals true, dispose all managed
// and unmanaged resources.
if (disposing)
{
_actionDispose();
}
// Note disposing has been done.
_disposed = true;
}
}
}
}
Y el uso de la misma:
_busyStackLifeTracker = new LifeTrackerStack
(
() =>
{
this.IsBusy = true;
},
() =>
{
this.IsBusy = false;
}
);
En todos los lugares donde corro mucho, hago:
using (this.BusyStackLifeTracker.GetNewLifeTracker())
{
// long job
}
Esto funciona para mi. ¡Espero que pueda ayudar a alguno! Eric
Tenga cuidado aquí porque jugar con el cursor de espera puede causar algunos problemas con los subprocesos de STA. Asegúrese de que si usa esto, lo está haciendo dentro de su propio hilo. Publiqué un ejemplo aquí Ejecutar dentro de una STA que usa esto para mostrar un WaitCursor mientras se inicia el archivo generado, y no explota (la aplicación principal) AFAICT.
Cambiar el cursor no significa que la aplicación no responderá a los eventos del mouse y del teclado después de que la tarea de ejecución prolongada haya finalizado. Para evitar que el usuario se engañe, utilizo la siguiente clase que elimina todos los mensajes del teclado y del mouse de la cola de mensajes de la aplicación.
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Input;
public class WpfHourGlass : IDisposable
{
[StructLayout(LayoutKind.Sequential)]
private struct POINTAPI
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
private struct MSG
{
public int hwnd;
public int message;
public int wParam;
public int lParam;
public int time;
public POINTAPI pt;
}
private const short PM_REMOVE = 0x1;
private const short WM_MOUSELAST = 0x209;
private const short WM_MOUSEFIRST = 0x200;
private const short WM_KEYFIRST = 0x100;
private const short WM_KEYLAST = 0x108;
[DllImport("user32", EntryPoint = "PeekMessageA", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int PeekMessage([MarshalAs(UnmanagedType.Struct)]
ref MSG lpMsg, int hwnd, int wMsgFilterMin, int wMsgFilterMax, int wRemoveMsg);
public WpfHourGlass()
{
Mouse.OverrideCursor = Cursors.Wait;
bActivated = true;
}
public void Show(bool Action = true)
{
if (Action)
{
Mouse.OverrideCursor = Cursors.Wait;
}
else
{
Mouse.OverrideCursor = Cursors.Arrow;
}
bActivated = Action;
}
#region "IDisposable Support"
// To detect redundant calls
private bool disposedValue;
private bool bActivated;
// IDisposable
protected virtual void Dispose(bool disposing)
{
if (!this.disposedValue)
{
if (disposing)
{
//remove todas as mensagens de mouse
//e teclado que tenham sido produzidas
//durante o processamento e estejam
//enfileiradas
if (bActivated)
{
MSG pMSG = new MSG();
while (Convert.ToBoolean(PeekMessage(ref pMSG, 0, WM_KEYFIRST, WM_KEYLAST, PM_REMOVE)))
{
}
while (Convert.ToBoolean(PeekMessage(ref pMSG, 0, WM_MOUSEFIRST, WM_MOUSELAST, PM_REMOVE)))
{
}
Mouse.OverrideCursor = Cursors.Arrow;
}
}
// TODO: free unmanaged resources (unmanaged objects) and override Finalize() below.
// TODO: set large fields to null.
}
this.disposedValue = true;
}
public void Dispose()
{
// Do not change this code. Put cleanup code in Dispose(ByVal disposing As Boolean) above.
Dispose(true);
GC.SuppressFinalize(this);
}
#endregion
}
Usé la solución de Olivier Jacot-Descombes, es muy simple y funciona bien. Gracias. actualización: incluso funciona bien sin usar un subproceso / trabajador en segundo plano diferente.
Lo uso con backgroudworker, el cursor del mouse se ve muy bien cuando está ocupado trabajando y vuelve a la normalidad cuando el trabajo está terminado.
public void pressButtonToDoSomeLongTimeWork()
{
Mouse.OverrideCursor = Cursors.Wait;
// before the long time work, change mouse cursor to wait cursor
worker.DoWork += doWorkLongTimeAsync;
worker.RunWorkerCompleted += worker_RunWorkerCompleted;
worker.RunWorkerAsync(); //start doing some long long time work but GUI can update
}
private void worker_RunWorkerCompleted(object sender,
RunWorkerCompletedEventArgs e)
{
//long time work is done();
updateGuiToShowTheLongTimeWorkResult();
Mouse.OverrideCursor = null; //return mouse cursor to normal
}
Sé que llego tarde, acabo de cambiar la forma en que administro el cursor Hourglass (estado ocupado) de mi aplicación.
Esta solución propuesta es más compleja que mi primera respuesta, pero creo que es más completa y mejor.
No dije que tenga una solución fácil o completa. Pero para mí es el mejor porque principalmente soluciona todos los problemas que tuve al administrar el estado ocupado de mi aplicación.
Ventajas:
El código se divide en algunas clases:
Este es el uso:
En eso:
public partial class App : Application
{
// ******************************************************************
protected override void OnStartup(StartupEventArgs e)
{
Global.Init(Application.Current.Dispatcher);
AppGlobal.Init(Application.Current.Dispatcher);
Uso preferido:
using (Global.Instance.GetDisposableBusyState())
{
...
}
Otro uso:
// ******************************************************************
public DlgAddAggregateCalc()
{
InitializeComponent();
Model = DataContext as DlgAddAggregateCalcViewModel;
this.Activated += OnActivated;
this.Deactivated += OnDeactivated;
}
// ************************************************************************
private void OnDeactivated(object sender, EventArgs eventArgs)
{
Global.Instance.PullState();
}
// ************************************************************************
private void OnActivated(object sender, EventArgs eventArgs)
{
Global.Instance.PushState(false);
}
Cursor de ventana automática:
public partial class DlgAddSignalResult : Window
{
readonly WindowWithAutoBusyState _autoBusyState = new WindowWithAutoBusyState();
// ******************************************************************
public DlgAddSignalResult()
{
InitializeComponent();
Model = DataContext as DlgAddSignalResultModel;
_autoBusyState.Init(this);
}
Código:
// Copyright (c) 2008 Daniel Grunwald
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without
// restriction, including without limitation the rights to use,
// copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following
// conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
// OTHER DEALINGS IN THE SOFTWARE.
/* Usage:
*
*
*
public delegate void FileChangedHandler(object sender, FileSystemEventArgs e);
[field: NonSerialized]
private readonly SmartWeakEvent<FileChangedHandler> _weakFileChanged = new SmartWeakEvent<FileChangedHandler>();
public event FileChangedHandler FileChanged
{
add
{
_weakFileChanged.Add(value);
}
remove
{
_weakFileChanged.Remove(value);
}
}
*
*
*/
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Reflection;
using System.Runtime.CompilerServices;
namespace HQ.Util.General.WeakEvent
{
/// <summary>
/// A class for managing a weak event.
/// </summary>
public sealed class SmartWeakEvent<T> where T : class
{
struct EventEntry
{
public readonly MethodInfo TargetMethod;
public readonly WeakReference TargetReference;
public EventEntry(MethodInfo targetMethod, WeakReference targetReference)
{
this.TargetMethod = targetMethod;
this.TargetReference = targetReference;
}
}
readonly List<EventEntry> eventEntries = new List<EventEntry>();
// EO: Added for ObservableCollectionWeak
public int CountOfDelegateEntry
{
get
{
RemoveDeadEntries();
return eventEntries.Count;
}
}
static SmartWeakEvent()
{
if (!typeof(T).IsSubclassOf(typeof(Delegate)))
throw new ArgumentException("T must be a delegate type");
MethodInfo invoke = typeof(T).GetMethod("Invoke");
if (invoke == null || invoke.GetParameters().Length != 2)
throw new ArgumentException("T must be a delegate type taking 2 parameters");
ParameterInfo senderParameter = invoke.GetParameters()[0];
if (senderParameter.ParameterType != typeof(object))
throw new ArgumentException("The first delegate parameter must be of type 'object'");
ParameterInfo argsParameter = invoke.GetParameters()[1];
if (!(typeof(EventArgs).IsAssignableFrom(argsParameter.ParameterType)))
throw new ArgumentException("The second delegate parameter must be derived from type 'EventArgs'");
if (invoke.ReturnType != typeof(void))
throw new ArgumentException("The delegate return type must be void.");
}
public void Add(T eh)
{
if (eh != null)
{
Delegate d = (Delegate)(object)eh;
if (d.Method.DeclaringType.GetCustomAttributes(typeof(CompilerGeneratedAttribute), false).Length != 0)
throw new ArgumentException("Cannot create weak event to anonymous method with closure.");
if (eventEntries.Count == eventEntries.Capacity)
RemoveDeadEntries();
WeakReference target = d.Target != null ? new WeakReference(d.Target) : null;
eventEntries.Add(new EventEntry(d.Method, target));
}
}
void RemoveDeadEntries()
{
eventEntries.RemoveAll(ee => ee.TargetReference != null && !ee.TargetReference.IsAlive);
}
public void Remove(T eh)
{
if (eh != null)
{
Delegate d = (Delegate)(object)eh;
for (int i = eventEntries.Count - 1; i >= 0; i--)
{
EventEntry entry = eventEntries[i];
if (entry.TargetReference != null)
{
object target = entry.TargetReference.Target;
if (target == null)
{
eventEntries.RemoveAt(i);
}
else if (target == d.Target && entry.TargetMethod == d.Method)
{
eventEntries.RemoveAt(i);
break;
}
}
else
{
if (d.Target == null && entry.TargetMethod == d.Method)
{
eventEntries.RemoveAt(i);
break;
}
}
}
}
}
public void Raise(object sender, EventArgs e)
{
int stepExceptionHelp = 0;
try
{
bool needsCleanup = false;
object[] parameters = {sender, e};
foreach (EventEntry ee in eventEntries.ToArray())
{
stepExceptionHelp = 1;
if (ee.TargetReference != null)
{
stepExceptionHelp = 2;
object target = ee.TargetReference.Target;
if (target != null)
{
stepExceptionHelp = 3;
ee.TargetMethod.Invoke(target, parameters);
}
else
{
needsCleanup = true;
}
}
else
{
stepExceptionHelp = 4;
ee.TargetMethod.Invoke(null, parameters);
}
}
if (needsCleanup)
{
stepExceptionHelp = 5;
RemoveDeadEntries();
}
stepExceptionHelp = 6;
}
catch (Exception ex)
{
string appName = Assembly.GetEntryAssembly().GetName().Name;
if (!EventLog.SourceExists(appName))
{
EventLog.CreateEventSource(appName, "Application");
EventLog.WriteEntry(appName,
String.Format("Exception happen in 'SmartWeakEvent.Raise()': {0}. Stack: {1}. Additional int: {2}.", ex.Message, ex.StackTrace, stepExceptionHelp), EventLogEntryType.Error);
}
throw;
}
}
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq.Expressions;
using System.Runtime.CompilerServices;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Threading;
using System.Xml.Serialization;
using HQ.Util.General.Log;
using HQ.Util.General.WeakEvent;
using JetBrains.Annotations;
// using System.Windows.Forms;
// using Microsoft.CSharp.RuntimeBinder;
// ATTENTION: Can only be used with Framework 4.0 and up
namespace HQ.Util.General.Notification
{
[Serializable]
public class NotifyPropertyChangedThreadSafeAsyncWeakBase : INotifyPropertyChanged
{
// ******************************************************************
[XmlIgnore]
[field: NonSerialized]
public SmartWeakEvent<PropertyChangedEventHandler> SmartPropertyChanged = new SmartWeakEvent<PropertyChangedEventHandler>();
[XmlIgnore]
[field: NonSerialized]
private Dispatcher _dispatcher = null;
// ******************************************************************
public event PropertyChangedEventHandler PropertyChanged
{
add
{
SmartPropertyChanged.Add(value);
}
remove
{
SmartPropertyChanged.Remove(value);
}
}
// ******************************************************************
[Browsable(false)]
[XmlIgnore]
public Dispatcher Dispatcher
{
get
{
if (_dispatcher == null)
{
_dispatcher = Application.Current?.Dispatcher;
if (_dispatcher == null)
{
if (Application.Current?.MainWindow != null)
{
_dispatcher = Application.Current.MainWindow.Dispatcher;
}
}
}
return _dispatcher;
}
set
{
if (_dispatcher == null && _dispatcher != value)
{
Debug.Print("Dispatcher has changed??? ");
}
_dispatcher = value;
}
}
// ******************************************************************
[NotifyPropertyChangedInvocator]
protected void NotifyPropertyChanged([CallerMemberName] String propertyName = null)
{
try
{
if (Dispatcher == null || Dispatcher.CheckAccess()) // Can be null in case of Console app
{
SmartPropertyChanged.Raise(this, new PropertyChangedEventArgs(propertyName));
}
else
{
Dispatcher.BeginInvoke(
new Action(() => SmartPropertyChanged.Raise(this, new PropertyChangedEventArgs(propertyName))));
}
}
catch (TaskCanceledException ex) // Prevent MT error when closing app...
{
Log.Log.Instance.AddEntry(LogType.LogException, "An exception occured when trying to notify.", ex);
}
}
// ******************************************************************
[NotifyPropertyChangedInvocator]
protected void NotifyPropertyChanged<T2>(Expression<Func<T2>> propAccess)
{
try
{
var asMember = propAccess.Body as MemberExpression;
if (asMember == null)
return;
string propertyName = asMember.Member.Name;
if (Dispatcher == null || Dispatcher.CheckAccess()) // Can be null in case of Console app
{
SmartPropertyChanged.Raise(this, new PropertyChangedEventArgs(propertyName));
}
else
{
Dispatcher.BeginInvoke(new Action(() => SmartPropertyChanged.Raise(this, new PropertyChangedEventArgs(propertyName))));
}
}
catch (TaskCanceledException ex) // Prevent MT error when closing app...
{
Log.Log.Instance.AddEntry(LogType.LogException, "An exception occured when trying to notify.", ex);
}
}
// ******************************************************************
protected bool UpdateField<T>(ref T field, T value, [CallerMemberName] string propertyName = null)
{
if (!EqualityComparer<T>.Default.Equals(field, value))
{
field = value;
NotifyPropertyChanged(propertyName);
return true;
}
return false;
}
// ******************************************************************
}
}
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Threading;
using HQ.Util.General.Notification;
namespace HQ.Util.General
{
/// <summary>
/// This is the centralized calss to obtain the Dispatcher in order to make sure to get the appropriate one (the MainWindow dispatcher).
/// If you need a specidifc thread dispatcher, please refer to System.Windows.Threading.Dispatcher or Dispatcher.CurrentDispatcher.
/// This dispatcher should be set at the initialization (start) of any GUI executable: ex: Global.Instance.Dispatcher = Application.Current.Dispatcher;
/// </summary>
public class Global : NotifyPropertyChangedThreadSafeAsyncWeakBase
{
public delegate void IsBusyChangeHandler(bool isBusy);
/// <summary>
/// This event happen only the UI thread in low priority
/// </summary>
public event IsBusyChangeHandler IsBusyChange;
private readonly ConcurrentStack<bool> _stackBusy = new ConcurrentStack<bool>();
// ******************************************************************
public static void Init(Dispatcher dispatcher)
{
Instance.Dispatcher = dispatcher;
}
// ******************************************************************
public static Global Instance = new Global();
// ******************************************************************
private Global()
{
_busyLifeTrackerStack = new LifeTrackerStack(() => PushState(), PullState);
}
// ******************************************************************
/// <summary>
/// Will set busy state temporary until object is disposed where
/// the state will be back to its previous state.
/// </summary>
/// <param name="isBusy"></param>
/// <returns></returns>
public LifeTracker GetDisposableBusyState(bool isBusy = true)
{
return new LifeTracker(() => PushState(isBusy), PullState);
}
// ******************************************************************
private bool _isBusy;
/// <summary>
/// This property should be use by the GUI part in order to control the mouse cursor
/// </summary>
public bool IsBusy
{
get => _isBusy;
private set
{
if (value == _isBusy) return;
_isBusy = value;
Dispatcher.BeginInvoke(new Action(() => IsBusyChange?.Invoke(_isBusy)), DispatcherPriority.ContextIdle);
NotifyPropertyChanged();
}
}
private readonly object _objLockBusyStateChange = new object();
// ******************************************************************
/// <summary>
/// Always prefer usage of "Using(Global.Instance.GetDisposableBusyState())" whenever possible.
/// Otherwise ensure to call Pull State to get back previous state of the cursor when action is
/// completed
/// </summary>
/// <param name="isBusy"></param>
public void PushState(bool isBusy = true)
{
lock (_objLockBusyStateChange)
{
_stackBusy.Push(isBusy);
IsBusy = isBusy;
}
}
// ******************************************************************
public void PullState()
{
lock (_objLockBusyStateChange)
{
_stackBusy.TryPop(out bool isBusy);
if (_stackBusy.TryPeek(out isBusy))
{
IsBusy = isBusy;
}
else
{
IsBusy = false;
}
}
}
// ******************************************************************
private readonly LifeTrackerStack _busyLifeTrackerStack = null;
/// <summary>
/// Only kept for historical reason / compatibility with previous code
/// </summary>
[Obsolete("Use direct 'using(Gloabl.Instance.GetDisposableBusyState(isBusy))' which is simpler")]
public LifeTrackerStack BusyLifeTrackerStack
{
get { return _busyLifeTrackerStack; }
}
// ******************************************************************
// private int _latestVersionExecuted = 0;
private int _currentVersionRequired = 0;
private readonly object _objLockRunOnce = new object();
private readonly Dictionary<int, GlobalRunOncePerQueueData> _actionsToRunOncePerQueue =
new Dictionary<int, GlobalRunOncePerQueueData>();
private readonly int _countOfRequestInQueue = 0;
/// <summary>
/// It will record all action once per key and it
/// once per Dispatcher queue roll over (on ContextIdle).
/// When the dispatcher reach the DispatcherPriority.ContextIdle, it will
/// run all action once.
/// Thread safe... no action will be lost but can be run twice or more if
/// some are added by other thread(s) at the same time one is executed.
/// </summary>
/// EO: sorry for the name but it is the best found
/// <param name="key"></param>
/// <param name="action"></param>
public void RunOncePerQueueRollOnDispatcherThread(int key, Action action)
{
lock (_objLockRunOnce)
{
if (!_actionsToRunOncePerQueue.TryGetValue(key, out GlobalRunOncePerQueueData data))
{
data = new GlobalRunOncePerQueueData(action);
_actionsToRunOncePerQueue.Add(key, data);
}
_currentVersionRequired++;
data.VersionRequired = _currentVersionRequired;
}
if (_countOfRequestInQueue <= 1)
{
Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.ContextIdle, new Action(ExecuteActions));
}
}
// ******************************************************************
private void ExecuteActions()
{
int versionExecute;
List<GlobalRunOncePerQueueData> datas = null;
lock (_objLockRunOnce)
{
versionExecute = _currentVersionRequired;
datas = _actionsToRunOncePerQueue.Values.ToList();
}
foreach (var data in datas)
{
data.Action();
}
lock (_objLockRunOnce)
{
List<int> keysToRemove = new List<int>();
foreach (var kvp in _actionsToRunOncePerQueue)
{
if (kvp.Value.VersionRequired <= versionExecute)
{
keysToRemove.Add(kvp.Key);
}
}
keysToRemove.ForEach(k => _actionsToRunOncePerQueue.Remove(k));
if (_actionsToRunOncePerQueue.Count == 0)
{
// _latestVersionExecuted = 0;
_currentVersionRequired = 0;
}
else
{
// _latestVersionExecuted = versionExecute;
}
}
}
// ******************************************************************
}
}
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;
using System.Windows.Threading;
using HQ.Util.General;
using HQ.Util.General.Notification;
using Microsoft.VisualBasic.Devices;
using System.Windows;
using Mouse = System.Windows.Input.Mouse;
using System.Threading;
namespace HQ.Wpf.Util
{
public class AppGlobal
{
// ******************************************************************
public static void Init(Dispatcher dispatcher)
{
if (System.Windows.Input.Keyboard.IsKeyDown(Key.LeftShift) || System.Windows.Input.Keyboard.IsKeyDown(Key.RightShift))
{
var res = MessageBox.Show($"'{AppInfo.AppName}' has been started with shift pressed. Do you want to wait for the debugger (1 minute wait)?", "Confirmation", MessageBoxButton.YesNo,
MessageBoxImage.Exclamation, MessageBoxResult.No);
if (res == MessageBoxResult.Yes)
{
var start = DateTime.Now;
while (!Debugger.IsAttached)
{
if ((DateTime.Now - start).TotalSeconds > 60)
{
break;
}
Thread.Sleep(100);
}
}
}
if (dispatcher == null)
{
throw new ArgumentNullException();
}
Global.Init(dispatcher);
Instance.Init();
}
// ******************************************************************
public static readonly AppGlobal Instance = new AppGlobal();
// ******************************************************************
private AppGlobal()
{
}
// ******************************************************************
private void Init()
{
Global.Instance.PropertyChanged += AppGlobalPropertyChanged;
}
// ******************************************************************
void AppGlobalPropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
{
if (e.PropertyName == "IsBusy")
{
if (Global.Instance.IsBusy)
{
if (Global.Instance.Dispatcher.CheckAccess())
{
Mouse.OverrideCursor = Cursors.Wait;
}
else
{
Global.Instance.Dispatcher.BeginInvoke(new Action(() => Mouse.OverrideCursor = Cursors.Wait));
}
}
else
{
if (Global.Instance.Dispatcher.CheckAccess())
{
Mouse.OverrideCursor = Cursors.Arrow;
}
else
{
Global.Instance.Dispatcher.BeginInvoke(new Action(() => Mouse.OverrideCursor = Cursors.Arrow));
}
}
}
}
// ******************************************************************
}
}
using HQ.Util.General;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Input;
namespace HQ.Wpf.Util
{
/// <summary>
/// Ensure window cursor is "normal" (arrow) when visible.
/// Usage: In Window class, define a member: OverrideCursorMtForWindow. Instantiate in constructor after Initialisation.
/// </summary>
public class WindowWithAutoBusyState
{
// ******************************************************************
Window _window;
bool _nextStateShoulBeVisible = true;
// ******************************************************************
public WindowWithAutoBusyState()
{
}
// ******************************************************************
public void Init(Window window)
{
_window = window;
_window.Cursor = Cursors.Wait;
_window.Loaded += (object sender, RoutedEventArgs e) => _window.Cursor = Cursors.Arrow;
_window.IsVisibleChanged += WindowIsVisibleChanged;
_window.Closed += WindowClosed;
}
// ******************************************************************
private void WindowIsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
{
if (_window.IsVisible)
{
if (_nextStateShoulBeVisible)
{
Global.Instance.PushState(false);
_nextStateShoulBeVisible = false;
}
}
else
{
if (!_nextStateShoulBeVisible)
{
Global.Instance.PullState();
_nextStateShoulBeVisible = true;
}
}
}
// ******************************************************************
private void WindowClosed(object sender, EventArgs e)
{
if (!_nextStateShoulBeVisible)
{
Global.Instance.PullState();
_nextStateShoulBeVisible = true;
}
}
// ******************************************************************
}
}