Add custom hotkeys to internal Unity Editor window

Hey @Aniki219,

The UnityEditor.Tilemaps.GridPaintingState class has the following public properties you can use:

• validTargets, which is all available tilemaps

• scenePaintTarget, which is the current active tilemap

If the properties you wanted to change happened to be private instead of public, you could still use Reflection to set them. Here is an example of using the properties above to change the active tilemap, and Reflection to change the active palette.

Editor/TilemapHelper.cs

 using System.Collections.Generic;
 using UnityEngine;
 using UnityEditor;
 using System.Linq;
 using UnityEditor.Tilemaps;
 
 public class TilemapHelper
 {
     [MenuItem("Custom Tools/Next Tilemap %&q")]
     static void SelectNextTilemap()
     {
         // Current/available tilemaps can be found in GridPaintingState
         var tilemaps = GridPaintingState.validTargets;
         var numTilemaps = tilemaps.Length;
         var currentTilemap = GridPaintingState.scenePaintTarget;
         // Handle trivial cases
         if (numTilemaps == 0) { return; }
         if (numTilemaps == 1) { GridPaintingState.scenePaintTarget = tilemaps[0]; return; }
         // Find current tilemap index
         var idx = 0;
         for (; idx < numTilemaps; idx++)
         {
             var tilemap = tilemaps[idx];
             if (tilemap == currentTilemap) { break; }
         }
         // Move to next tilemap, with wraparound
         idx = (idx + 1) % numTilemaps;
         // Set new tilemap
         GridPaintingState.scenePaintTarget = tilemaps[idx];
     }
     
     [MenuItem("Custom Tools/Next Palette %&e")]
     static void SelectNextPalette()
     {
         // Find current/all palettes using reflection
         var knownType = typeof(GridPaintingState);
         var assembly = knownType.Assembly;
         var assmeblyTypes = assembly.GetTypes();
         var wndType = assmeblyTypes.Single(x => x.Name == "GridPaintPaletteWindow");
         var wnd = EditorWindow.GetWindow(wndType);
         var currentPaletteProp = wndType.GetProperty("palette");
         var currentPalette = (GameObject)currentPaletteProp.GetValue(wnd);
         var gridPalettesType = assmeblyTypes.Single(x => x.Name == "GridPalettes");
         var palettesProp = gridPalettesType.GetProperty("palettes");
         var palettes = (List<GameObject>)palettesProp.GetValue(gridPalettesType);
         var numPalettes = palettes.Count;
         // Handle trivial cases
         if (numPalettes == 0) { return; }
         if (numPalettes == 1) { currentPaletteProp.SetValue(wnd, palettes[0]); return; }
         // Find current palette and choose next
         GameObject newPalette = null;
         for (var i = 0; i < numPalettes; i++) 
         {
             if (palettes[i] == currentPalette) 
             {
                 var nextIdx = (i + 1) % numPalettes;
                 newPalette = palettes[nextIdx];
                 break;
             }
         }
         // Set palette using reflection
         currentPaletteProp.SetValue(wnd, newPalette);
     }
 }

Hope this helps!