Merge pull request #1932 from VictoriousRaptor/FixPreviewHotkey

Fix preview hotkey issue

Author: jjw24

Flow.Launcher.Infrastructure/Hotkey/HotkeyModel.cs

@@ -1,8 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Linq;
 using System.Windows.Input;
-using System.Windows.Navigation;
 
 namespace Flow.Launcher.Infrastructure.Hotkey
 {
@@ -99,7 +99,7 @@ private void Parse(string hotkeyString)
                 {
                     try
                     {
-                        CharKey = (Key) Enum.Parse(typeof (Key), charKey);
+                        CharKey = (Key)Enum.Parse(typeof(Key), charKey);
                     }
                     catch (ArgumentException)
                     {
@@ -137,8 +137,13 @@ public override string ToString()
             }
             return string.Join(" + ", keys);
         }
-
-        public bool Validate()
+        
+        /// <summary>
+        /// Validate hotkey
+        /// </summary>
+        /// <param name="validateKeyGestrue">Try to validate hotkey as a KeyGesture.</param>
+        /// <returns></returns>
+        public bool Validate(bool validateKeyGestrue = false)
         {
             switch (CharKey)
             {
@@ -150,21 +155,57 @@ public bool Validate()
                 case Key.RightShift:
                 case Key.LWin:
                 case Key.RWin:
+                case Key.None:
                     return false;
                 default:
+                    if (validateKeyGestrue)
+                    {
+                        try
+                        {
+                            KeyGesture keyGesture = new KeyGesture(CharKey, ModifierKeys);
+                        }
+                        catch (System.Exception e) when (e is NotSupportedException || e is InvalidEnumArgumentException)
+                        {
+                            return false;
+                        }
+                    }
                     if (ModifierKeys == ModifierKeys.None)
                     {
-                        return !((CharKey >= Key.A && CharKey <= Key.Z) ||
-                            (CharKey >= Key.D0 && CharKey <= Key.D9) ||
-                            (CharKey >= Key.NumPad0 && CharKey <= Key.NumPad9));
+                        return !IsPrintableCharacter(CharKey);
                     }
                     else
                     {
-                        return CharKey != Key.None;
+                        return true;
                     }
             }
         }
 
+        private static bool IsPrintableCharacter(Key key)
+        {
+            // https://stackoverflow.com/questions/11881199/identify-if-a-event-key-is-text-not-only-alphanumeric
+            return (key >= Key.A && key <= Key.Z) ||
+                   (key >= Key.D0 && key <= Key.D9) ||
+                   (key >= Key.NumPad0 && key <= Key.NumPad9) ||
+                   key == Key.OemQuestion ||
+                   key == Key.OemQuotes ||
+                   key == Key.OemPlus ||
+                   key == Key.OemOpenBrackets ||
+                   key == Key.OemCloseBrackets ||
+                   key == Key.OemMinus ||
+                   key == Key.DeadCharProcessed ||
+                   key == Key.Oem1 ||
+                   key == Key.Oem7 ||
+                   key == Key.OemPeriod ||
+                   key == Key.OemComma ||
+                   key == Key.OemMinus ||
+                   key == Key.Add ||
+                   key == Key.Divide ||
+                   key == Key.Multiply ||
+                   key == Key.Subtract ||
+                   key == Key.Oem102 ||
+                   key == Key.Decimal;
+        }
+
         public override bool Equals(object obj)
         {
             if (obj is HotkeyModel other)

Flow.Launcher/HotkeyControl.xaml.cs

@@ -19,6 +19,11 @@ public partial class HotkeyControl : UserControl
 
         public event EventHandler HotkeyChanged;
 
+        /// <summary>
+        /// Designed for Preview Hotkey and KeyGesture.
+        /// </summary>
+        public bool ValidateKeyGesture { get; set; } = false;
+
         protected virtual void OnHotkeyChanged() => HotkeyChanged?.Invoke(this, EventArgs.Empty);
 
         public HotkeyControl()
@@ -68,7 +73,7 @@ public async Task SetHotkeyAsync(HotkeyModel keyModel, bool triggerValidate = tr
 
             if (triggerValidate)
             {
-                bool hotkeyAvailable = CheckHotkeyAvailability(keyModel);
+                bool hotkeyAvailable = CheckHotkeyAvailability(keyModel, ValidateKeyGesture);
                 CurrentHotkeyAvailable = hotkeyAvailable;
                 SetMessage(hotkeyAvailable);
                 OnHotkeyChanged();
@@ -91,13 +96,13 @@ public async Task SetHotkeyAsync(HotkeyModel keyModel, bool triggerValidate = tr
                 CurrentHotkey = keyModel;
             }
         }
-
+        
         public Task SetHotkeyAsync(string keyStr, bool triggerValidate = true)
         {
             return SetHotkeyAsync(new HotkeyModel(keyStr), triggerValidate);
         }
 
-        private static bool CheckHotkeyAvailability(HotkeyModel hotkey) => hotkey.Validate() && HotKeyMapper.CheckAvailability(hotkey);
+        private static bool CheckHotkeyAvailability(HotkeyModel hotkey, bool validateKeyGesture) => hotkey.Validate(validateKeyGesture) && HotKeyMapper.CheckAvailability(hotkey);
 
         public new bool IsFocused => tbHotkey.IsFocused;
 

Flow.Launcher/SettingWindow.xaml

@@ -2448,6 +2448,7 @@
                                                 Width="300"
                                                 Height="35"
                                                 Margin="0,0,0,0"
+                                                ValidateKeyGesture="True"
                                                 HorizontalAlignment="Right"
                                                 HorizontalContentAlignment="Right"
                                                 Loaded="OnPreviewHotkeyControlLoaded"

Flow.Launcher/ViewModel/MainViewModel.cs

@@ -24,6 +24,7 @@
 using CommunityToolkit.Mvvm.Input;
 using System.Globalization;
 using System.Windows.Input;
+using System.ComponentModel;
 
 namespace Flow.Launcher.ViewModel
 {
@@ -583,7 +584,24 @@ public double MainWindowWidth
 
         public string OpenResultCommandModifiers => Settings.OpenResultModifiers;
 
-        public string PreviewHotkey => Settings.PreviewHotkey;
+        public string PreviewHotkey 
+        { 
+            get
+            {
+                // TODO try to patch issue #1755
+                // Added in v1.14.0, remove after v1.16.0. 
+                try
+                {
+                    var converter = new KeyGestureConverter();
+                    var key = (KeyGesture)converter.ConvertFromString(Settings.PreviewHotkey);
+                }
+                catch (Exception e) when (e is NotSupportedException || e is InvalidEnumArgumentException)
+                {
+                    Settings.PreviewHotkey = "F1";
+                }
+                return Settings.PreviewHotkey;
+            }
+        }
 
         public string Image => Constant.QueryTextBoxIconImagePath;