Per una vista costruita utilizzando WPF, voglio cambiare il cursore del mouse in una clessidra quando l'applicazione è occupata e non risponde.
Una soluzione è aggiungere
this.Cursor = Cursors.Wait;a tutti i punti che potrebbero causare la mancata risposta dell'interfaccia utente. Ma ovviamente questa non è la soluzione migliore. Mi chiedo qual è il modo migliore per ottenere questo risultato?
È possibile ottenere questo risultato utilizzando stili o risorse?
Grazie,
Risposte:
Abbiamo creato una classe usa e getta che cambia il cursore per noi quando l'app impiegherà molto tempo, assomiglia a questo:
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
}E lo usiamo in questo modo:
using(new WaitCursor())
{
// very long task
}Potrebbe non essere il miglior design, ma fa il trucco =)
using(uiServices.ShowWaitCursor()). Sembra macchinoso ma facilita i test di unità.
Ho usato le risposte qui per costruire qualcosa che funzionasse meglio per me. Il problema è che quando termina il blocco using nella risposta di Carlo, l'interfaccia utente potrebbe essere ancora impegnata nell'associazione dati. Potrebbero esserci dati caricati in modo lento o eventi che si attivano come risultato di ciò che è stato fatto nel blocco. Nel mio caso a volte ci sono voluti diversi secondi dalla scomparsa del cursore di attesa fino a quando l'interfaccia utente era effettivamente pronta. L'ho risolto creando un metodo helper che imposta il waitcursor e si occupa anche di impostare un timer che reimposta automaticamente il cursore quando l'interfaccia utente è pronta. Non posso essere sicuro che questo design funzionerà in tutti i casi, ma ha funzionato per me:
/// <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();
}
}
}Sto semplicemente facendo
Mouse.OverrideCursor = Cursors.Wait;
try {
// Long lasting stuff ...
} finally {
Mouse.OverrideCursor = null;
}Secondo la documentazione della proprietà Mouse.OverrideCursor
Per cancellare l'override Cursor, impostare OverrideCursor su null.
L'istruzione try-finalmente assicura che il cursore predefinito venga ripristinato in ogni caso, anche quando si verifica un'eccezione o la parte try viene lasciata con returno break(se all'interno di un ciclo).
Il modo migliore sarebbe non far sì che l'interfaccia utente diventi mai reattiva, scaricando tutto il lavoro su altri thread / attività come appropriato.
Oltre a questo, sei un po 'in un catch-22: se hai aggiunto un modo per rilevare che l'interfaccia utente non risponde, non c'è un buon modo per cambiare il cursore, poiché il posto in cui dovresti farlo ( il thread pari) non risponde ... Potresti essere in grado di bloccare il codice standard win32 per cambiare il cursore per l'intera finestra, però?
Altrimenti, dovresti farlo preventivamente, come suggerisce la tua domanda.
Personalmente preferisco non vedere il puntatore del mouse passare molte volte da clessidra a freccia. Per aiutare a prevenire questo comportamento durante la chiamata di funzioni incorporate che richiedono un po 'di tempo e ciascuna tenta di controllare il puntatore del mouse, utilizzo uno stack (contatore) che chiamo LifeTrackerStack. E solo quando la pila è vuota (contatore a 0) che ho impostato la clessidra su una freccia.
Uso anche MVVM. Preferisco anche il codice thread-safe.
Nella mia classe radice del modello dichiaro il mio LifeTrackerStack che popolo le classi del modello figlio o uso direttamente dalle classi del modello figlio quando ho accesso ad esso da esse.
Il mio tracker di vita ha 2 stati / azioni:
Quindi, a mio avviso, mi associo manualmente al mio Model.IsBusy e faccio:
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));
}
}Questa è la mia classe 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;
}
}
}
}E il suo utilizzo:
_busyStackLifeTracker = new LifeTrackerStack
(
() =>
{
this.IsBusy = true;
},
() =>
{
this.IsBusy = false;
}
);Ovunque faccio jogging a lungo, faccio:
using (this.BusyStackLifeTracker.GetNewLifeTracker())
{
// long job
}Per me funziona. Spero che possa aiutare chiunque! Eric
Fai attenzione qui perché armeggiare con il cursore di attesa può causare alcuni problemi con i thread STA. Assicurati che se usi questa cosa lo stai facendo all'interno del suo thread. Ho postato un esempio qui passano all'interno di uno STA che utilizza questo per mostrare un WaitCursor mentre il file generato si sta avviando, e non saltare in aria (l'applicazione principale) AFAICT.
La modifica del cursore non significa che l'applicazione non risponderà agli eventi del mouse e della tastiera al termine dell'attività a lunga esecuzione. Per evitare errori di lettura dell'utente, utilizzo la classe seguente che rimuove tutti i messaggi della tastiera e del mouse dalla coda dei messaggi dell'applicazione.
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
}Ho usato la soluzione di Olivier Jacot-Descombes, è molto semplice e funziona bene. Grazie. aggiornamento: funziona bene anche senza utilizzare thread / background worker diversi.
Lo uso con backgroudworker, il cursore del mouse ha un bell'aspetto quando è impegnato a lavorare e torna alla normalità quando il lavoro è finito.
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
}So di essere in ritardo, ho appena cambiato il modo in cui gestisco il cursore Hourglass (stato occupato) della mia applicazione.
Questa soluzione proposta è più complessa della mia prima risposta ma penso sia più completa e migliore.
Non ho detto che ho una soluzione facile o completa. Ma per me è il migliore perché risolve principalmente tutti i problemi che avevo nella gestione dello stato occupato della mia applicazione.
Vantaggi:
Il codice è suddiviso in poche classi:
Questo è l'utilizzo:
Dentro:
public partial class App : Application
{
// ******************************************************************
protected override void OnStartup(StartupEventArgs e)
{
Global.Init(Application.Current.Dispatcher);
AppGlobal.Init(Application.Current.Dispatcher);Utilizzo preferito:
using (Global.Instance.GetDisposableBusyState())
{
...
}Altro utilizzo:
// ******************************************************************
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);
}Cursore finestra automatica:
public partial class DlgAddSignalResult : Window
{
readonly WindowWithAutoBusyState _autoBusyState = new WindowWithAutoBusyState();
// ******************************************************************
public DlgAddSignalResult()
{
InitializeComponent();
Model = DataContext as DlgAddSignalResultModel;
_autoBusyState.Init(this);
}Codice:
// 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;
}
}
// ******************************************************************
}
}