Changed, Texture Browser: "Used Textures" group is now collapsible.

Source/Core/Controls/ImageBrowserControl.cs

@@ -303,6 +303,7 @@ namespace CodeImp.DoomBuilder.Controls
 					if(n == selected) continue;
 					if(n.Text == selected.Text) 
 					{
+						if(list.IsGroupCollapsed(n.Group)) list.SetGroupCollapsed(n.Group, false);
 						n.Selected = true;
 						n.Focused = true;
 						n.EnsureVisible();
@@ -417,6 +418,20 @@ namespace CodeImp.DoomBuilder.Controls
 			list.Groups.Add(grp);
 			return grp;
 		}
+
+		//mxd
+		public bool IsGroupCollapsed(ListViewGroup group)
+		{
+			if(!list.Groups.Contains(group)) return false;
+			return list.IsGroupCollapsed(group);
+		}
+
+		//mxd. This enables group collapsability and optionally collapses it
+		public void SetGroupCollapsed(ListViewGroup group, bool collapse)
+		{
+			if(!list.Groups.Contains(group)) return;
+			list.SetGroupCollapsed(group, collapse);
+		}
 		
 		// This begins adding items
 		public void BeginAdding(bool keepselectedindex)

Source/Core/Controls/OptimizedListView.cs

@@ -16,6 +16,9 @@
 
 #region ================== Namespaces
 
+using System;
+using System.Reflection;
+using System.Runtime.InteropServices;
 using System.Windows.Forms;
 
 #endregion
@@ -24,22 +27,57 @@ namespace CodeImp.DoomBuilder.Controls
 {
 	public class OptimizedListView : ListView
 	{
-		#region ================== Constants
+		#region ================== API Declarations
+
+		[DllImport("user32.dll")]
+		private static extern int SendMessage(IntPtr window, int message, int wParam, ref LVGROUP lParam);
 
 		#endregion
 
-		#region ================== Variables
+		#region ================== Structs
+
+		[StructLayout(LayoutKind.Sequential)]
+		private struct LVGROUP
+		{
+			public int cbSize;
+			public int mask;
+			[MarshalAs(UnmanagedType.LPTStr)]
+			public string pszHeader;
+			public int cchHeader;
+			[MarshalAs(UnmanagedType.LPTStr)]
+			public string pszFooter;
+			public int cchFooter;
+			public int iGroupId;
+			public int stateMask;
+			public int state;
+			public int uAlign;
+		}
 
 		#endregion
 
-		#region ================== Properties
+		#region ================== Enums
+
+		[Flags]
+		private enum GroupState
+		{
+			COLLAPSIBLE = 8,
+			COLLAPSED = 1,
+			EXPANDED = 0
+		}
+
+		#endregion
+
+		#region ================== Delegates
+
+		private delegate bool CallBackSetGroupCollapsible(ListViewGroup group, bool collapsed);
+		private delegate bool CallBackGetGroupCollapsed(ListViewGroup group);
 
 		#endregion
 
 		#region ================== Constructor
 
 		// Constructor
-		public OptimizedListView() : base()
+		public OptimizedListView()
 		{
 			this.DoubleBuffered = true;
 			SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
@@ -49,6 +87,73 @@ namespace CodeImp.DoomBuilder.Controls
 
 		#region ================== Methods
 
+		//mxd. Collapsible groups support. Created using http://www.codeproject.com/Articles/31276/Add-Group-Collapse-Behavior-on-a-Listview-Control as a reference
+		public bool SetGroupCollapsed(ListViewGroup group, bool collapsed) 
+		{
+			// Insanity checks...
+			if(!this.Groups.Contains(group)) return false;
+			if(Environment.OSVersion.Version.Major < 6) return false; //Only Vista and forward allows collapse of ListViewGroups
+			if(this.InvokeRequired) return (bool)this.Invoke(new CallBackSetGroupCollapsible(SetGroupCollapsed), group, collapsed);
+
+			LVGROUP groupstruct = new LVGROUP();
+			groupstruct.cbSize = Marshal.SizeOf(typeof(LVGROUP));
+			groupstruct.state = (int)((collapsed ? GroupState.COLLAPSED : GroupState.EXPANDED) | GroupState.COLLAPSIBLE);
+			groupstruct.stateMask = (int)(GroupState.COLLAPSIBLE | GroupState.COLLAPSED);
+			groupstruct.mask = 4; // LVGF_STATE 
+			SendMessage(this.Handle, 0x1000 + 147, GetGroupID(group), ref groupstruct); // #define LVM_SETGROUPINFO (LVM_FIRST + 147)
+
+			return true;
+		}
+
+		//mxd. Collapsible groups support. Created using http://fed.googlecode.com/svn/trunk/Plain.Forms/ListViewGroupEx.cs as a reference
+		public bool IsGroupCollapsed(ListViewGroup group) 
+		{
+			// Insanity checks...
+			if(!this.Groups.Contains(group)) return false;
+			if(Environment.OSVersion.Version.Major < 6) return false; //Only Vista and forward allows collapse of ListViewGroups
+			if(this.InvokeRequired) return (bool)this.Invoke(new CallBackGetGroupCollapsed(IsGroupCollapsed), group);
+
+			LVGROUP groupstruct = new LVGROUP();
+			groupstruct.cbSize = Marshal.SizeOf(typeof(LVGROUP));
+			groupstruct.stateMask = (int)(GroupState.COLLAPSIBLE | GroupState.COLLAPSED);
+			groupstruct.mask = 4; // LVGF_STATE
+
+			SendMessage(this.Handle, 0x1000 + 149, GetGroupID(group), ref groupstruct); // #define LVM_GETGROUPINFO (LVM_FIRST + 149)
+			return (groupstruct.state & (int)GroupState.COLLAPSED) != 0;
+		}
+
+		//mxd.
+		private static int GetGroupID(ListViewGroup group) 
+		{
+			int id = int.MinValue;
+			Type grouptype = group.GetType();
+
+			PropertyInfo pi = grouptype.GetProperty("ID", BindingFlags.NonPublic | BindingFlags.Instance);
+			if(pi != null) 
+			{
+				object idprop = pi.GetValue(group, null);
+				if(idprop != null) id = (int)idprop;
+			}
+
+			return id;
+		}
+
+		//mxd. Required to make "Expand/Collapse" group header button work.
+		protected override void WndProc(ref Message m) 
+		{
+			switch(m.Msg) 
+			{
+				case 0x202: // WM_LBUTTONUP
+					base.DefWndProc(ref m);
+					base.WndProc(ref m);
+					break;
+
+				default:
+					base.WndProc(ref m);
+					break;
+			}
+		}
+
 		#endregion
 	}
 }

Source/Core/Windows/TextureBrowserForm.cs

@@ -39,6 +39,7 @@ namespace CodeImp.DoomBuilder.Windows
 		private readonly ListViewGroup availgroup;
 		private TreeNode selectedset; //mxd
 		private string selecttextureonfill;
+		private readonly bool usedgroupcollapsed; //mxd
 		private readonly bool browseflats; //mxd
 		
 		// Properties
@@ -80,6 +81,10 @@ namespace CodeImp.DoomBuilder.Windows
 			usedgroup = browser.AddGroup("Used " + imagetype + ":");
 			availgroup = browser.AddGroup("Available " + imagetype + ":");
 
+			//mxd. Make "Used" group collapsible
+			usedgroupcollapsed = General.Settings.ReadSetting("browserwindow.usedgroupcollapsed", false);
+			browser.SetGroupCollapsed(usedgroup, usedgroupcollapsed);
+
 			//mxd. Fill texture sets list with normal texture sets
 			foreach(IFilledTextureSet ts in General.Map.Data.TextureSets) 
 			{
@@ -455,6 +460,7 @@ namespace CodeImp.DoomBuilder.Windows
 			General.Settings.WriteSetting("browserwindow.windowstate", windowstate);
 			if(!splitter.IsCollapsed) General.Settings.WriteSetting("browserwindow.splitterdistance", splitter.SplitPosition); //mxd
 			General.Settings.WriteSetting("browserwindow.splittercollapsed", splitter.IsCollapsed); //mxd
+			General.Settings.WriteSetting("browserwindow.usedgroupcollapsed", browser.IsGroupCollapsed(usedgroup)); //mxd
 
 			//mxd. Save last selected texture set, if it's not "All" (it will be selected anyway if search for initial texture set fails)
 			if(this.DialogResult == DialogResult.OK && tvTextureSets.SelectedNodes.Count > 0 && !(tvTextureSets.SelectedNodes[0].Tag is AllTextureSet))
@@ -534,7 +540,7 @@ namespace CodeImp.DoomBuilder.Windows
 			// Select texture
 			if(!string.IsNullOrEmpty(selecttextureonfill))
 			{
-				browser.SelectItem(selecttextureonfill, usedgroup);
+				browser.SelectItem(selecttextureonfill, (usedgroupcollapsed ? availgroup : usedgroup)); //mxd. availgroup/usedgroup switch.
 				selecttextureonfill = null;
 			}