[FZEditor]Gain focus after launching the editor (#25827)

* [Power Toys - Fancy Zones] Focus problem when activating layour editor is solved.

* haveTriedToGetFocusAlready variable added for focusing one time.

* [Power Toys - Fancy Zones] Functions are added to NativeMethods.cs

src/modules/fancyzones/editor/FancyZonesEditor/MainWindow.xaml.cs

@@ -5,11 +5,13 @@
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.Runtime.InteropServices;
 using System.Windows;
 using System.Windows.Automation;
 using System.Windows.Automation.Peers;
 using System.Windows.Controls;
 using System.Windows.Input;
+using System.Windows.Interop;
 using Common.UI;
 using FancyZonesEditor.Models;
 using FancyZonesEditor.Utils;
@@ -34,6 +36,8 @@ namespace FancyZonesEditor
         private ContentDialog _openedDialog;
         private TextBlock _createLayoutAnnounce;
 
+        private bool haveTriedToGetFocusAlready;
+
         public int WrapPanelItemSize { get; set; } = DefaultWrapPanelItemSize;
 
         public MainWindow(bool spanZonesAcrossMonitors, Rect workArea)
@@ -63,6 +67,42 @@ namespace FancyZonesEditor
             _settings.InitModels();
         }
 
+        private void BringToFront()
+        {
+            // Get the window handle of the FancyZones Editor window
+            IntPtr handle = new WindowInteropHelper(this).Handle;
+
+            // Get the handle of the window currently in the foreground
+            IntPtr foregroundWindowHandle = NativeMethods.GetForegroundWindow();
+
+            // Get the thread IDs of the current thread and the thread of the foreground window
+            uint currentThreadId = NativeMethods.GetCurrentThreadId();
+            uint activeThreadId = NativeMethods.GetWindowThreadProcessId(foregroundWindowHandle, IntPtr.Zero);
+
+            // Check if the active thread is different from the current thread
+            if (activeThreadId != currentThreadId)
+            {
+                // Attach the input processing mechanism of the current thread to the active thread
+                NativeMethods.AttachThreadInput(activeThreadId, currentThreadId, true);
+
+                // Set the FancyZones Editor window as the foreground window
+                NativeMethods.SetForegroundWindow(handle);
+
+                // Detach the input processing mechanism of the current thread from the active thread
+                NativeMethods.AttachThreadInput(activeThreadId, currentThreadId, false);
+            }
+            else
+            {
+                // Set the FancyZones Editor window as the foreground window
+                NativeMethods.SetForegroundWindow(handle);
+            }
+
+            // Bring the FancyZones Editor window to the foreground and activate it
+            NativeMethods.SwitchToThisWindow(handle, true);
+
+            haveTriedToGetFocusAlready = true;
+        }
+
         public void Update()
         {
             DataContext = _settings;
@@ -408,6 +448,11 @@ namespace FancyZonesEditor
         // This is required to fix a WPF rendering bug when using custom chrome
         private void OnContentRendered(object sender, EventArgs e)
         {
+            if (!haveTriedToGetFocusAlready)
+            {
+                BringToFront();
+            }
+
             InvalidateVisual();
         }
 

src/modules/fancyzones/editor/FancyZonesEditor/NativeMethods.cs

@@ -15,5 +15,24 @@ namespace FancyZonesEditor
 
         [DllImport("kernel32", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
         public static extern IntPtr GetProcAddress(IntPtr hModule, string procName);
+
+        [DllImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        public static extern bool SetForegroundWindow(IntPtr hWnd);
+
+        [DllImport("user32.dll")]
+        public static extern void SwitchToThisWindow(IntPtr hWnd, bool fAltTab);
+
+        [DllImport("user32.dll")]
+        public static extern IntPtr GetForegroundWindow();
+
+        [DllImport("user32.dll")]
+        public static extern uint GetWindowThreadProcessId(IntPtr hWnd, IntPtr processId);
+
+        [DllImport("kernel32.dll")]
+        public static extern uint GetCurrentThreadId();
+
+        [DllImport("user32.dll")]
+        public static extern bool AttachThreadInput(uint idAttach, uint idAttachTo, bool fAttach);
     }
 }