diff --git a/core/dvxWidget.h b/core/dvxWidget.h
index 73c2a93..bd8b7d1 100644
--- a/core/dvxWidget.h
+++ b/core/dvxWidget.h
@@ -136,7 +136,6 @@ typedef enum {
 // Flags encode static properties checked by the framework.
 // Widgets set these in their WidgetClassT definition.
 #define WCLASS_FOCUSABLE           0x00000001
-#define WCLASS_BOX_CONTAINER       0x00000002
 #define WCLASS_HORIZ_CONTAINER     0x00000004
 #define WCLASS_PAINTS_CHILDREN     0x00000008
 #define WCLASS_NO_HIT_RECURSE      0x00000010
diff --git a/core/dvxWidgetPlugin.h b/core/dvxWidgetPlugin.h
index 4e434a3..16c9e46 100644
--- a/core/dvxWidgetPlugin.h
+++ b/core/dvxWidgetPlugin.h
@@ -128,7 +128,6 @@ WidgetT *widgetFindByAccel(WidgetT *root, char key);
 int32_t widgetCountVisibleChildren(const WidgetT *w);
 int32_t widgetFrameBorderWidth(const WidgetT *w);
 bool widgetIsFocusable(int32_t type);
-bool widgetIsBoxContainer(int32_t type);
 bool widgetIsHorizContainer(int32_t type);
 int32_t multiClickDetect(int32_t vx, int32_t vy);
 
diff --git a/core/widgetCore.c b/core/widgetCore.c
index 9e675de..b9dae6c 100644
--- a/core/widgetCore.c
+++ b/core/widgetCore.c
@@ -527,21 +527,6 @@ bool widgetIsFocusable(int32_t type) {
 }
 
 
-// ============================================================
-// widgetIsBoxContainer
-// ============================================================
-//
-// Returns true for widget types that use the generic box layout.
-
-bool widgetIsBoxContainer(int32_t type) {
-    if (type < 0 || type >= arrlen(widgetClassTable) || !widgetClassTable[type]) {
-        return false;
-    }
-
-    return (widgetClassTable[type]->flags & WCLASS_BOX_CONTAINER) != 0;
-}
-
-
 // ============================================================
 // widgetIsHorizContainer
 // ============================================================
diff --git a/core/widgetLayout.c b/core/widgetLayout.c
index 070b32b..b0470d3 100644
--- a/core/widgetLayout.c
+++ b/core/widgetLayout.c
@@ -128,9 +128,7 @@ void widgetCalcMinSizeBox(WidgetT *w, const BitmapFontT *font) {
 // size calculation. Hints only increase the minimum, never shrink it.
 
 void widgetCalcMinSizeTree(WidgetT *w, const BitmapFontT *font) {
-    if (widgetIsBoxContainer(w->type)) {
-        widgetCalcMinSizeBox(w, font);
-    } else if (wclsHas(w, WGT_METHOD_CALC_MIN_SIZE)) {
+    if (wclsHas(w, WGT_METHOD_CALC_MIN_SIZE)) {
         wclsCalcMinSize(w, font);
     } else {
         w->calcMinW = 0;
@@ -357,9 +355,7 @@ void widgetLayoutBox(WidgetT *w, const BitmapFontT *font) {
 // do nothing (they have no children to lay out).
 
 void widgetLayoutChildren(WidgetT *w, const BitmapFontT *font) {
-    if (widgetIsBoxContainer(w->type)) {
-        widgetLayoutBox(w, font);
-    } else if (wclsHas(w, WGT_METHOD_LAYOUT)) {
+    if (wclsHas(w, WGT_METHOD_LAYOUT)) {
         wclsLayout(w, font);
     }
 }
diff --git a/widgets/box/widgetBox.c b/widgets/box/widgetBox.c
index bef74f0..5e5a384 100644
--- a/widgets/box/widgetBox.c
+++ b/widgets/box/widgetBox.c
@@ -141,21 +141,31 @@ void widgetFrameDestroy(WidgetT *w) {
 
 static const WidgetClassT sClassVBox = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER,
+    .flags   = 0,
+    .handlers = {
+        [WGT_METHOD_CALC_MIN_SIZE] = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]        = (void *)widgetLayoutBox,
+    }
 };
 
 static const WidgetClassT sClassHBox = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER | WCLASS_HORIZ_CONTAINER,
+    .flags   = WCLASS_HORIZ_CONTAINER,
+    .handlers = {
+        [WGT_METHOD_CALC_MIN_SIZE] = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]        = (void *)widgetLayoutBox,
+    }
 };
 
 static const WidgetClassT sClassFrame = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER | WCLASS_FOCUS_FORWARD,
+    .flags   = WCLASS_FOCUS_FORWARD,
     .handlers = {
         [WGT_METHOD_PAINT]              = (void *)widgetFramePaint,
         [WGT_METHOD_DESTROY]            = (void *)widgetFrameDestroy,
         [WGT_METHOD_GET_LAYOUT_METRICS] = (void *)widgetFrameGetLayoutMetrics,
+        [WGT_METHOD_CALC_MIN_SIZE]      = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]             = (void *)widgetLayoutBox,
     }
 };
 
diff --git a/widgets/radio/widgetRadio.c b/widgets/radio/widgetRadio.c
index fe1a7ba..c095a98 100644
--- a/widgets/radio/widgetRadio.c
+++ b/widgets/radio/widgetRadio.c
@@ -310,9 +310,11 @@ void widgetRadioSetText(WidgetT *w, const char *text) {
 
 static const WidgetClassT sClassRadioGroup = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER,
+    .flags   = 0,
     .handlers = {
-        [WGT_METHOD_DESTROY] = (void *)widgetRadioGroupDestroy,
+        [WGT_METHOD_DESTROY]       = (void *)widgetRadioGroupDestroy,
+        [WGT_METHOD_CALC_MIN_SIZE] = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]        = (void *)widgetLayoutBox,
     }
 };
 
diff --git a/widgets/statusBar/widgetStatusBar.c b/widgets/statusBar/widgetStatusBar.c
index c17847d..a15b5d2 100644
--- a/widgets/statusBar/widgetStatusBar.c
+++ b/widgets/statusBar/widgetStatusBar.c
@@ -72,10 +72,12 @@ void widgetStatusBarGetLayoutMetrics(const WidgetT *w, const BitmapFontT *font,
 
 static const WidgetClassT sClassStatusBar = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER | WCLASS_HORIZ_CONTAINER,
+    .flags   = WCLASS_HORIZ_CONTAINER,
     .handlers = {
         [WGT_METHOD_PAINT]              = (void *)widgetStatusBarPaint,
         [WGT_METHOD_GET_LAYOUT_METRICS] = (void *)widgetStatusBarGetLayoutMetrics,
+        [WGT_METHOD_CALC_MIN_SIZE]      = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]             = (void *)widgetLayoutBox,
     }
 };
 
diff --git a/widgets/tabControl/widgetTabControl.c b/widgets/tabControl/widgetTabControl.c
index e913505..d71023f 100644
--- a/widgets/tabControl/widgetTabControl.c
+++ b/widgets/tabControl/widgetTabControl.c
@@ -596,10 +596,12 @@ static const WidgetClassT sClassTabControl = {
 
 static const WidgetClassT sClassTabPage = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER | WCLASS_ACCEL_WHEN_HIDDEN,
+    .flags   = WCLASS_ACCEL_WHEN_HIDDEN,
     .handlers = {
         [WGT_METHOD_ON_ACCEL_ACTIVATE] = (void *)widgetTabPageAccelActivate,
         [WGT_METHOD_DESTROY]           = (void *)widgetTabPageDestroy,
+        [WGT_METHOD_CALC_MIN_SIZE]     = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]            = (void *)widgetLayoutBox,
     }
 };
 
diff --git a/widgets/toolbar/widgetToolbar.c b/widgets/toolbar/widgetToolbar.c
index 9612243..9b82fab 100644
--- a/widgets/toolbar/widgetToolbar.c
+++ b/widgets/toolbar/widgetToolbar.c
@@ -64,10 +64,12 @@ void widgetToolbarGetLayoutMetrics(const WidgetT *w, const BitmapFontT *font, in
 
 static const WidgetClassT sClassToolbar = {
     .version = WGT_CLASS_VERSION,
-    .flags   = WCLASS_BOX_CONTAINER | WCLASS_HORIZ_CONTAINER,
+    .flags   = WCLASS_HORIZ_CONTAINER,
     .handlers = {
         [WGT_METHOD_PAINT]              = (void *)widgetToolbarPaint,
         [WGT_METHOD_GET_LAYOUT_METRICS] = (void *)widgetToolbarGetLayoutMetrics,
+        [WGT_METHOD_CALC_MIN_SIZE]      = (void *)widgetCalcMinSizeBox,
+        [WGT_METHOD_LAYOUT]             = (void *)widgetLayoutBox,
     }
 };