support standard mouse cursors

src/dlangui/platforms/common/platform.d

@@ -282,7 +282,7 @@ class Window {
         return res;
     }
 
-    protected bool dispatchMouseEvent(Widget root, MouseEvent event) {
+    protected bool dispatchMouseEvent(Widget root, MouseEvent event, ref bool cursorIsSet) {
         // only route mouse events to visible widgets
         if (root.visibility != Visibility.Visible)
             return false;
@@ -291,9 +291,16 @@ class Window {
         // offer event to children first
         for (int i = 0; i < root.childCount; i++) {
             Widget child = root.child(i);
-            if (dispatchMouseEvent(child, event))
+            if (dispatchMouseEvent(child, event, cursorIsSet))
                 return true;
         }
+		if (event.action == MouseAction.Move && !cursorIsSet) {
+			uint cursorType = root.getCursorType(event.x, event.y);
+			if (cursorType != CursorType.Parent) {
+				setCursorType(cursorType);
+				cursorIsSet = true;
+			}
+		}
         // if not processed by children, offer event to root
         if (sendAndCheckOverride(root, event)) {
             debug(mouse) Log.d("MouseEvent is processed");
@@ -445,6 +452,7 @@ class Window {
         if (event.action == MouseAction.Move || event.action == MouseAction.Leave) {
             processed = checkRemoveTracking(event);
         }
+		bool cursorIsSet = false;
         if (!res) {
             bool insideOneOfPopups = false;
             for (int i = cast(int)_popups.length - 1; i >= 0; i--) {
@@ -458,11 +466,11 @@ class Window {
                     if (p.onMouseEventOutside(event)) // stop loop when true is returned, but allow other main widget to handle event
                         break;
                 } else {
-                    if (dispatchMouseEvent(p, event))
+                    if (dispatchMouseEvent(p, event, cursorIsSet))
                         return true;
                 }
             }
-            res = dispatchMouseEvent(_mainWidget, event);
+            res = dispatchMouseEvent(_mainWidget, event, cursorIsSet);
         }
         return res || processed || _mainWidget.needDraw;
     }
@@ -485,6 +493,10 @@ class Window {
         for (int i = 0; i < root.childCount; i++)
             checkUpdateNeeded(root.child(i), needDraw, needLayout, animationActive);
     }
+	/// sets cursor type for window
+	protected void setCursorType(uint cursorType) {
+		// override to support different mouse cursors
+	}
     /// checks content widgets for necessary redraw and/or layout
     bool checkUpdateNeeded(ref bool needDraw, ref bool needLayout, ref bool animationActive) {
         needDraw = needLayout = animationActive = false;

src/dlangui/platforms/sdl/sdlapp.d

@@ -144,6 +144,69 @@ version(USE_SDL) {
 			invalidate();
 		}
 
+		protected uint _lastCursorType = CursorType.None;
+		protected SDL_Cursor * [uint] _cursorMap;
+		/// sets cursor type for window
+		override protected void setCursorType(uint cursorType) {
+			// override to support different mouse cursors
+			if (_lastCursorType != cursorType) {
+				_lastCursorType = cursorType;
+				if (cursorType in _cursorMap) {
+					Log.d("changing cursor to ", cursorType);
+					SDL_SetCursor(_cursorMap[cursorType]);
+					return;
+				}
+				SDL_Cursor * cursor;
+				switch (cursorType) {
+					case CursorType.Arrow:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_ARROW);
+						break;
+					case CursorType.IBeam:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_ARROW);
+						break;
+					case CursorType.Wait:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_WAIT);
+						break;
+					case CursorType.WaitArrow:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_WAITARROW);
+						break;
+					case CursorType.Crosshair:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_CROSSHAIR);
+						break;
+					case CursorType.No:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_NO);
+						break;
+					case CursorType.Hand:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_HAND);
+						break;
+					case CursorType.SizeNWSE:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENWSE);
+						break;
+					case CursorType.SizeNESW:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENESW);
+						break;
+					case CursorType.SizeWE:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEWE);
+						break;
+					case CursorType.SizeNS:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENS);
+						break;
+					case CursorType.SizeAll:
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEALL);
+						break;
+					default:
+						// TODO: support custom cursors
+						cursor = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_ARROW);
+						break;
+				}
+				if (cursor) {
+					Log.d("changing cursor to ", cursorType);
+					_cursorMap[cursorType] = cursor;
+					SDL_SetCursor(cursor);
+				}
+			}
+		}
+
         SDL_Texture * _texture;
         int _txw;
         int _txh;

src/dlangui/widgets/editors.d

@@ -936,6 +936,7 @@ class EditWidgetBase : WidgetGroup, EditableContentListener, MenuItemActionHandl
 				return super.isActionEnabled(action);
 		}
 	}
+
 	/// shows popup at (x,y)
 	override void showPopupMenu(int x, int y) {
 		/// if preparation signal handler assigned, call it; don't show popup if false is returned from handler
@@ -960,6 +961,12 @@ class EditWidgetBase : WidgetGroup, EditableContentListener, MenuItemActionHandl
 		// TODO
 	}
 
+	/// returns mouse cursor type for widget
+	override uint getCursorType(int x, int y) {
+		return CursorType.IBeam;
+	}
+	
+
     /// when true, Tab / Shift+Tab presses are processed internally in widget (e.g. insert tab character) instead of focus change navigation.
     @property bool wantTabs() {
         return _wantTabs;

src/dlangui/widgets/widget.d

@@ -85,6 +85,25 @@ enum FocusMovement {
     Right,
 }
 
+/// standard mouse cursor types
+enum CursorType {
+	None,
+	/// use parent's cursor
+	Parent,
+	Arrow,
+	IBeam,
+	Wait,
+	Crosshair,
+	WaitArrow,
+	SizeNWSE,
+	SizeNESW,
+	SizeWE,
+	SizeNS,
+	SizeAll,
+	No,
+	Hand
+}
+
 class Widget {
     /// widget id
     protected string _id;
@@ -121,6 +140,11 @@ class Widget {
     /// set new trackHover flag value (when true, widget will change Hover state while mouse is moving)
     @property Widget trackHover(bool v) { _trackHover = v; return this; }
 
+	/// returns mouse cursor type for widget
+	uint getCursorType(int x, int y) {
+		return CursorType.Arrow;
+	}
+
 	debug(resalloc) {
 	    private static int _instanceCount = 0;
         private static bool _appShuttingDown = false;