diff --git a/src/dlangui/core/events.d b/src/dlangui/core/events.d
index 5e9f9eea..0265237c 100644
--- a/src/dlangui/core/events.d
+++ b/src/dlangui/core/events.d
@@ -240,24 +240,44 @@ enum MouseAction : ubyte {
 
 /// mouse flag bits
 enum MouseFlag : ushort {
-    /// Ctrl key is down
-	Control = 0x0008,
+    // mouse buttons
     /// Left mouse button is down
 	LButton = 0x0001,
     /// Middle mouse button is down
 	MButton = 0x0010,
     /// Right mouse button is down
 	RButton = 0x0002,
-    /// Shift key is down
-	Shift   = 0x0004,
     /// X1 mouse button is down
 	XButton1= 0x0020,
     /// X2 mouse button is down
 	XButton2= 0x0040,
+
+    // keyboard modifiers
+    /// Ctrl key is down
+	Control = 0x0008,
+    /// Shift key is down
+	Shift   = 0x0004,
     /// Alt key is down
-	Alt     = 0x0080
+	Alt     = 0x0080,
 }
 
+/// mouse button
+enum MouseButton : ubyte {
+    /// no button
+    None,
+    /// left mouse button
+    Left = MouseFlag.LButton,
+    /// right mouse button
+    Right = MouseFlag.RButton,
+    /// right mouse button
+    Middle = MouseFlag.MButton,
+    /// additional mouse button 1
+    XButton1 = MouseFlag.XButton1, // additional button 1
+    /// additional mouse button 2
+    XButton2 = MouseFlag.XButton2, // additional button 2
+}
+
+
 /// mouse button state details
 struct ButtonDetails {
 	/// Clock.currStdTime() for down event of this button (0 if button is up).
@@ -297,22 +317,6 @@ struct ButtonDetails {
     @property ushort downFlags() { return _downFlags; }
 }
 
-/// mouse button
-enum MouseButton : ubyte {
-    /// no button
-    None,
-    /// left mouse button
-    Left,
-    /// right mouse button
-    Right,
-    /// right mouse button
-    Middle,
-    /// additional mouse button 1
-    XButton1, // additional button
-    /// additional mouse button 2
-    XButton2, // additional button
-}
-
 /// mouse event
 class MouseEvent {
     protected long _eventTimestamp;
diff --git a/src/dlangui/core/types.d b/src/dlangui/core/types.d
index dbafdc6c..0cdff181 100644
--- a/src/dlangui/core/types.d
+++ b/src/dlangui/core/types.d
@@ -41,8 +41,11 @@ module dlangui.core.types;
 
 import std.algorithm;
 
+/// 2D point
 struct Point {
+    /// x coordinate
     int x;
+    /// y coordinate
     int y;
     this(int x0, int y0) {
         x = x0;
@@ -50,25 +53,35 @@ struct Point {
     }
 }
 
+/// 2D rectangle
 struct Rect {
+    /// x coordinate of top left corner
     int left;
+    /// y coordinate of top left corner
     int top;
+    /// x coordinate of bottom right corner
     int right;
+    /// y coordinate of bottom right corner
     int bottom;
+    /// returns average of left, right
     @property int middlex() { return (left + right) / 2; }
+    /// returns average of top, bottom
     @property int middley() { return (top + bottom) / 2; }
+    /// add offset to horizontal and vertical coordinates
     void offset(int dx, int dy) {
         left += dx;
         right += dx;
         top += dy;
         bottom += dy;
     }
+    /// expand rectangle dimensions
     void expand(int dx, int dy) {
         left -= dx;
         right += dx;
         top -= dy;
         bottom += dy;
     }
+    /// shrink rectangle dimensions
     void shrink(int dx, int dy) {
         left += dx;
         right -= dx;
@@ -97,6 +110,7 @@ struct Rect {
     @property bool empty() {
         return right <= left || bottom <= top;
     }
+    /// translate rectangle coordinates by (x,y) - add deltax to x coordinates, and deltay to y coordinates
     void moveBy(int deltax, int deltay) {
         left += deltax;
         right += deltax;
@@ -187,10 +201,13 @@ class RefCountedObject {
     ~this() {}
 }
 
+/// reference counting
 struct Ref(T) { // if (T is RefCountedObject)
     private T _data;
     alias get this;
+    /// returns true if object is not assigned
     @property bool isNull() const { return _data is null; }
+    /// returns counter of references
     @property int refCount() const { return _data !is null ? _data.refCount : 0; }
     this(T data) {
         _data = data;
@@ -231,15 +248,18 @@ struct Ref(T) { // if (T is RefCountedObject)
             _data.addRef();
 		return this;
     }
+    /// clears reference
     void clear() { 
         if (_data !is null) {
             _data.releaseRef();
             _data = null;
         }
     }
+    /// returns object reference (null if not assigned)
 	@property T get() {
 		return _data;
 	}
+    /// returns const reference from const object
 	@property const(T) get() const {
 		return _data;
 	}
@@ -249,8 +269,10 @@ struct Ref(T) { // if (T is RefCountedObject)
     }
 }
 
-
+//================================================================================
 // some utility functions
+
+
 string fromStringz(const(char[]) s) {
     if (s is null)
         return null;
diff --git a/src/dlangui/widgets/grid.d b/src/dlangui/widgets/grid.d
index 314b32d6..85a27d64 100644
--- a/src/dlangui/widgets/grid.d
+++ b/src/dlangui/widgets/grid.d
@@ -125,6 +125,11 @@ class StringGridWidget : GridWidgetBase {
     protected int _scrollCol; 
     /// row scroll offset, relative to last fixed row; 0 = not scrolled
     protected int _scrollRow;
+    /// selected cell column
+    protected int _col;
+    /// selected cell row
+    protected int _row;
+
 	this(string ID = null) {
 		super(ID);
 		_headerCols = 1;
@@ -135,6 +140,13 @@ class StringGridWidget : GridWidgetBase {
 		addChild(_hscrollbar);
 		styleId = "EDIT_BOX";
         resize(20, 30);
+        _col = 3;
+        _row = 4;
+        for (int y = 1; y < _rows; y++) {
+            for (int x = 1; x < _cols; x++) {
+                _data[y][x] = "cell("d ~ to!dstring(x) ~ ","d ~ to!dstring(y) ~ ")"d;
+            }
+        }
 	}
 	@property override int cols() {
 		return _cols;
@@ -202,7 +214,7 @@ class StringGridWidget : GridWidgetBase {
         for (int i = _cols; i < cols; i++) {
             if (i >= _headerCols)
                 _data[0][i] = genColHeader(i - _headerCols);
-            _colWidths[i] = i == 0 ? 20 : 80;
+            _colWidths[i] = i == 0 ? 20 : 100;
         }
 		_rowHeights.length = rows;
         int fontHeight = font.height;
@@ -254,6 +266,82 @@ class StringGridWidget : GridWidgetBase {
         }
         return rc;
     }
+    
+    /// converts client rect relative coordinates to cell coordinates
+    bool pointToCell(int x, int y, ref int col, ref int row, ref Rect cellRect) {
+        col = row = -1;
+        cellRect = Rect();
+        Rect rc;
+        int xx = 0;
+        for (int i = 0; i < _cols; i++) {
+            rc.left = xx;
+            xx += colWidth(i);
+            rc.right = xx;
+            if (rc.left < rc.right && x >= rc.left && x < rc.right) {
+                col = i;
+                break;
+            }
+            if (xx > x)
+                break;
+        }
+        int yy = 0;
+        for (int i = 0; i < _rows; i++) {
+            rc.top = yy;
+            yy += rowHeight(i);
+            rc.bottom = yy;
+            
+            if (rc.top < rc.bottom && y >= rc.top && y < rc.bottom) {
+                row = i;
+                break;
+            }
+            if (yy > y)
+                break;
+        }
+        if (col >= 0 && row >= 0) {
+            cellRect = rc;
+            return true;
+        }
+        return false;
+    }
+
+    /// handle mouse wheel events
+    override bool onMouseEvent(MouseEvent event) {
+        if (visibility != Visibility.Visible)
+            return false;
+        int c, r; // col, row
+        Rect rc;
+        bool cellFound = false;
+        bool normalCell = false;
+        // convert coordinates
+        if (event.action == MouseAction.ButtonUp || event.action == MouseAction.ButtonDown || event.action == MouseAction.Move) {
+            int x = event.x;
+            int y = event.y;
+            x -= _clientRect.left;
+            y -= _clientRect.top;
+            cellFound = pointToCell(x, y, c, r, rc);
+            normalCell = c >= _fixedCols && r >= _fixedRows;
+        }
+        if (event.action == MouseAction.ButtonDown && event.button == MouseButton.Left) {
+            if (cellFound && normalCell) {
+                _col = c;
+                _row = r;
+                invalidate();
+            }
+            return true;
+        }
+        if (event.action == MouseAction.Move && (event.flags & MouseFlag.LButton)) {
+            // TODO: selection
+            if (cellFound && normalCell) {
+                _col = c;
+                _row = r;
+                invalidate();
+            }
+            return true;
+        }
+        return super.onMouseEvent(event);
+    }
+
+
 	/// returns row header title
 	dstring rowTitle(int row) {
 		return _rowTitles[row];
@@ -331,7 +419,7 @@ class StringGridWidget : GridWidgetBase {
 
 	/// draw cell content
 	void drawCell(DrawBuf buf, Rect rc, int col, int row) {
-        rc.shrink(1, 1);
+        rc.shrink(2, 1);
 		FontRef fnt = font;
         dstring txt = cellText(col, row);
         Point sz = fnt.textSize(txt);
@@ -351,15 +439,23 @@ class StringGridWidget : GridWidgetBase {
         vborder.left = vborder.right - 1;
         hborder.top = hborder.bottom - 1;
         hborder.right--;
+        bool selectedCol = _col == col;
+        bool selectedRow = _row == row;
+        bool selectedCell = selectedCol && selectedRow;
         if (col < _headerCols || row < _headerRows) {
             // draw header cell background
-            buf.fillRect(rc, 0x80808080);
-            buf.fillRect(vborder, 0x80FFFFFF);
-            buf.fillRect(hborder, 0x80FFFFFF);
+            uint cl = 0x80909090;
+            if (selectedCol || selectedRow)
+                cl = 0x80FFC040;
+            buf.fillRect(rc, cl);
+            buf.fillRect(vborder, 0x80202020);
+            buf.fillRect(hborder, 0x80202020);
         } else {
             // normal cell background
             buf.fillRect(vborder, 0x80C0C0C0);
             buf.fillRect(hborder, 0x80C0C0C0);
+            if (selectedCell)
+                buf.drawFrame(rc, 0x404040FF, Rect(1,1,1,1), 0xC0FFFF00);
         }
 	}