Only use XCreateImage when drawing the Alt theme indicator on macOS, not on UNIX or Windows.

2 files changed, 46 insertions, 9 deletions

diff --git a/generic/ttk/ttkDefaultTheme.c b/generic/ttk/ttkDefaultTheme.c
index 20ba013..473caba 100644
--- a/generic/ttk/ttkDefaultTheme.c
+++ b/generic/ttk/ttkDefaultTheme.c
@@ -18,6 +18,10 @@ static const int WIN32_XDRAWLINE_HACK = 1;
 static const int WIN32_XDRAWLINE_HACK = 0;
 #endif
 
+#if defined(MAC_OSX_TK)
+  #define IGNORES_VISUAL
+#endif
+
 #define BORDERWIDTH     2
 #define SCROLLBAR_WIDTH 14
 #define MIN_THUMB_SIZE  8
@@ -551,20 +555,47 @@ static void IndicatorElementDraw(
      * Create a scratch buffer to store the image:
      */
 
+#if defined(IGNORES_VISUAL)
+
+    /*
+     * Platforms which ignore the VisualInfo can use XCreateImage to get the
+     * scratch image.  This is essential on macOS, where it is not safe to call
+     * XGetImage in a display procedure.
+     */
+
     img = XCreateImage(display, NULL, 32, ZPixmap, 0, NULL,
 		       (unsigned int)spec->width, (unsigned int)spec->height,
 		       0, 0);
+#else
+
+    /*
+     * This trick allows creating the scratch XImage without having to
+     * construct a VisualInfo.
+     */
+
+    img = XGetImage(display, d, 0, 0,
+		    (unsigned int)spec->width, (unsigned int)spec->height,
+		    AllPlanes, ZPixmap);
+#endif
+
     if (img == NULL) {
-      return;
+        return;
     }
+
+#if defined(IGNORES_VISUAL)
+
     img->data = ckalloc(img->bytes_per_line * img->height);
     if (img->data == NULL) {
-      return;
+        XDestroyImage(img);
+	return;
     }
 
+#endif
+
     /*
-     * Create the image, painting it into an XImage one pixel at a time.
+     * Create the image, painting it into the XImage one pixel at a time.
      */
+
     index = Ttk_StateTableLookup(spec->map, state);
     for (iy=0 ; iy<spec->height ; iy++) {
 	for (ix=0 ; ix<spec->width ; ix++) {
@@ -574,16 +605,18 @@ static void IndicatorElementDraw(
     }
 
     /*
-     * Copy onto our target drawable surface.
+     * Copy the image onto our target drawable surface.
      */
+
     memset(&gcValues, 0, sizeof(gcValues));
     copyGC = Tk_GetGC(tkwin, 0, &gcValues);
     TkPutImage(NULL, 0, display, d, copyGC, img, 0, 0, b.x, b.y,
                spec->width, spec->height);
 
     /*
-     * Tidy up.
+     * Tidy up. Note that XDestroyImage frees img->data.
      */
+
     Tk_FreeGC(display, copyGC);
     XDestroyImage(img);
 }
diff --git a/generic/ttk/ttkTheme.c b/generic/ttk/ttkTheme.c
index ac52595..c0bd784 100644
--- a/generic/ttk/ttkTheme.c
+++ b/generic/ttk/ttkTheme.c
@@ -18,6 +18,13 @@
 
 #define PKG_ASSOC_KEY "Ttk"
 
+#ifdef MAC_OSX_TK
+    extern void TkMacOSXFlushWindows(void);
+    #define UPDATE_WINDOWS() TkMacOSXFlushWindows()
+#else
+    #define UPDATE_WINDOWS()
+#endif
+
 /*------------------------------------------------------------------------
  * +++ Styles.
  *
@@ -513,10 +520,7 @@ static void ThemeChangedProc(ClientData clientData)
 	Tcl_BackgroundException(pkgPtr->interp, code);
     }
     pkgPtr->themeChangePending = 0;
-#ifdef MAC_OSX_TK
-    extern void TkMacOSXFlushWindows(void);
-    TkMacOSXFlushWindows();
-#endif
+    UPDATE_WINDOWS();
 }
 
 /*