1 files changed, 57 insertions, 13 deletions

diff --git a/alf/alfpanel.cpp b/alf/alfpanel.cpp
index 2f39ef1..eb954ec 100644
--- a/alf/alfpanel.cpp
+++ b/alf/alfpanel.cpp
@@ -6,6 +6,8 @@ typedef struct {
     ALFLayout layout;
     ALFColor bgcolor;
     HFONT font;
+    const ALFPanelVTable *vtbl;
+    void *closure;
 } ALFPanelPriv;
 
 static void
@@ -24,30 +26,34 @@ ALF_Panel_ClearPriv(ALFPanelPriv *priv)
 static void
 ALF_Panel_Paint(ALFPanelPriv *priv, HWND hwnd, HDC dc, RECT *r)
 {
-    if (priv->bgcolor == ALF_COLOR_TRANSPARENT) {
+    if (priv->vtbl && priv->vtbl->paint) {
+        priv->vtbl->paint(priv->closure, hwnd, dc, r);
+    } else if (priv->bgcolor == ALF_COLOR_TRANSPARENT) {
         ALF_Compat_DrawThemeParentBackground(hwnd, dc, r);
     } else {
         ALF_FillRect(dc, r, priv->bgcolor);
     }
 }
 
-static LRESULT WINAPI
-ALF__PanelWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
+void
+ALF_Panel_SetVTable(HWND panel, const ALFPanelVTable *vtbl, void *closure)
 {
-    if (msg == WM_NCCREATE) {
-        ALFPanelPriv *p = ALF_New(ALFPanelPriv, 1);
+    SendMessage(panel, ALF_WM_PANEL_SETVTABLE, (WPARAM)vtbl, (LPARAM)closure);
+}
 
-        ALF_Panel_IntializePriv(p);
+LRESULT
+ALF_Panel_DefWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
+{
+    ALFPanelPriv *priv = (ALFPanelPriv *)GetWindowLongPtr(window, 0);
 
-        SetWindowLongPtr(window, 0, (LONG_PTR)p);
+    if (msg == WM_CREATE) {
+        if (priv->vtbl && priv->vtbl->create)
+            priv->vtbl->create(priv->closure, window);
     }
 
-    ALFPanelPriv *priv = (ALFPanelPriv *)GetWindowLongPtr(window, 0);
-
-    if (msg == WM_NCDESTROY) {
-        ALF_Panel_ClearPriv(priv);
-        ALF_Free(priv);
-        SetWindowLongPtr(window, 0, 0);
+    if (msg == WM_DESTROY) {
+        if (priv->vtbl && priv->vtbl->destroy)
+            priv->vtbl->destroy(priv->closure, window);
     }
 
     if (msg == WM_ERASEBKGND) {
@@ -87,6 +93,7 @@ ALF__PanelWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
         GetClientRect(window, &r);
 
         ALF_Panel_Paint(priv, window, (HDC)wparam, &r);
+
         return TRUE;
     }
 
@@ -101,6 +108,12 @@ ALF__PanelWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
         return 0;
     }
 
+    if (msg == ALF_WM_PANEL_SETVTABLE) {
+        priv->vtbl = (const ALFPanelVTable *)wparam;
+        priv->closure = (void *)lparam;
+        return TRUE;
+    }
+
     if (ALF_ShouldMessageBubble(window, msg, wparam, lparam))
         return SendMessage(GetParent(window), msg, wparam, lparam);
 
@@ -115,6 +128,37 @@ ALF__PanelWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
     return DefWindowProc(window, msg, wparam, lparam);
 }
 
+static LRESULT WINAPI
+ALF__PanelWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
+{
+    if (msg == WM_NCCREATE) {
+        ALFPanelPriv *p = ALF_New(ALFPanelPriv, 1);
+
+        ALF_Panel_IntializePriv(p);
+
+        SetWindowLongPtr(window, 0, (LONG_PTR)p);
+    }
+
+    ALFPanelPriv *priv = (ALFPanelPriv *)GetWindowLongPtr(window, 0);
+
+    if (msg == WM_NCDESTROY) {
+        ALF_Panel_ClearPriv(priv);
+        ALF_Free(priv);
+        priv = NULL;
+        SetWindowLongPtr(window, 0, 0);
+    }
+
+    if (priv) {
+        if (priv->vtbl && priv->vtbl->message) {
+            return priv->vtbl->message(priv->closure, window, msg, wparam, lparam);
+        } else {
+            return ALF_Panel_DefWindowProc(window, msg, wparam, lparam);
+        }
+    } else {
+        return DefWindowProc(window, msg, wparam, lparam);
+    }
+}
+
 void
 ALF_RegisterPanelClass(void)
 {