diff --git a/example.cpp b/example.cpp
index 6e0158d..858b875 100644
--- a/example.cpp
+++ b/example.cpp
@@ -30,6 +30,10 @@ typedef enum {
     ST_RADIO = 2,
     // progress slider 
     ST_SLIDER = 3,
+    // column
+    ST_COLUMN = 4,
+    // row
+    ST_ROW = 5,
 } SubType;
 
 typedef struct {
@@ -66,26 +70,39 @@ void init(NVGcontext *vg) {
 // the container the item is in has negative spacing, and the item
 // is first or last element in a sequence of 2 or more elements.
 int cornerFlags(int item) {
-    /*
     int parent = uiParent(item);
-    int spacing = uiGetSpacing(parent);
-    if (spacing >= 0) return BND_CORNER_NONE;
     int numkids = uiGetChildCount(parent);
-    int numid = uiGetChildId(item);
     if (numkids < 2) return BND_CORNER_NONE;
-    UIuvec2 flags = uiGetLayoutFlags(parent);
-    if (flags.x & UI_LAYOUT_PACK) {
-        if (!numid) return BND_CORNER_RIGHT;
-        else if (numid == numkids-1) return BND_CORNER_LEFT;
-        else return BND_CORNER_ALL;
-    } else if (flags.y & UI_LAYOUT_PACK) {
-        if (!numid) return BND_CORNER_DOWN;
-        else if (numid == numkids-1) return BND_CORNER_TOP;
-        else return BND_CORNER_ALL;
-    }*/
+    const UIData *head = (const UIData *)uiGetData(parent);
+    if (head) {
+        int numid = uiGetChildId(item);
+        switch(head->subtype) {
+        case ST_COLUMN: {
+                if (!numid) return BND_CORNER_DOWN;
+                else if (numid == numkids-1) return BND_CORNER_TOP;
+                else return BND_CORNER_ALL;
+        } break;
+        case ST_ROW: {
+                if (!numid) return BND_CORNER_RIGHT;
+                else if (numid == numkids-1) return BND_CORNER_LEFT;
+                else return BND_CORNER_ALL;
+        } break;
+        default: break;
+        }
+    }
     return BND_CORNER_NONE;
 }
 
+void testrect(NVGcontext *vg, UIrect rect) {
+#if 0    
+    nvgBeginPath(vg);
+    nvgRect(vg,rect.x+0.5,rect.y+0.5,rect.w-1,rect.h-1);
+    nvgStrokeColor(vg,nvgRGBf(1,0,0));
+    nvgStrokeWidth(vg,1);
+    nvgStroke(vg);    
+#endif    
+}
+
 void drawUI(NVGcontext *vg, int item, int x, int y) {
     const UIData *head = (const UIData *)uiGetData(item);
     UIrect rect = uiGetRect(item);
@@ -93,7 +110,9 @@ void drawUI(NVGcontext *vg, int item, int x, int y) {
     rect.y += y; 
     if (head) {
         switch(head->subtype) {
-            default:
+            default: {
+                testrect(vg,rect);
+            } break;
             case ST_LABEL: {
                 assert(head);
                 const UIButtonData *data = (UIButtonData*)head;
@@ -126,11 +145,7 @@ void drawUI(NVGcontext *vg, int item, int x, int y) {
             } break;
         }
     } else {
-        nvgBeginPath(vg);
-        nvgRect(vg,rect.x+0.5,rect.y+0.5,rect.w-1,rect.h-1);
-        nvgStrokeColor(vg,nvgRGBf(1,0,0));
-        nvgStrokeWidth(vg,1);
-        nvgStroke(vg);
+        testrect(vg,rect);
     }
     
     int kid = uiFirstChild(item);
@@ -140,58 +155,92 @@ void drawUI(NVGcontext *vg, int item, int x, int y) {
     }
 }
 
-int label(int iconid, const char *label) {    
+int label(int parent, int iconid, const char *label) {    
     int item = uiItem();
     uiSetSize(item, 0, BND_WIDGET_HEIGHT);
     UIButtonData *data = (UIButtonData *)uiAllocData(item, sizeof(UIButtonData));
     data->head.subtype = ST_LABEL;
     data->iconid = iconid;
     data->label = label;
+    uiAppend(parent, item);
     return item;
 }
 
-int button(UIhandle handle, int iconid, const char *label, 
+void demohandler(int item, UIevent event) {
+    const UIButtonData *data = (const UIButtonData *)uiGetData(item);
+    printf("clicked: %lld %s\n", uiGetHandle(item), data->label);
+}
+
+int button(int parent, UIhandle handle, int iconid, const char *label, 
     UIhandler handler) {
-    int item = uiItem();
+    // create new ui item
+    int item = uiItem(); 
+    // set persistent handle for item that is used
+    // to track activity over time
     uiSetHandle(item, handle);
+    // set size of wiget; horizontal size is dynamic, vertical is fixed
     uiSetSize(item, 0, BND_WIDGET_HEIGHT);
+    // attach event handler e.g. demohandler above
     uiSetHandler(item, handler, UI_BUTTON0_HOT_UP);
+    // store some custom data with the button that we use for styling
     UIButtonData *data = (UIButtonData *)uiAllocData(item, sizeof(UIButtonData));
     data->head.subtype = ST_BUTTON;
     data->iconid = iconid;
     data->label = label;
+    uiAppend(parent, item);
     return item;
 }
 
 // simple logic for a slider
+
+// starting offset of the currently active slider
 static float sliderstart = 0.0;
+
+// event handler for slider (same handler for all sliders)
 void sliderhandler(int item, UIevent event) {
+    // retrieve the custom data we saved with the slider
     UISliderData *data = (UISliderData *)uiGetData(item);
     switch(event) {
         default: break;
         case UI_BUTTON0_DOWN: {
+            // button was pressed for the first time; capture initial
+            // slider value.
             sliderstart = *data->progress;
         } break;
         case UI_BUTTON0_CAPTURE: {
+            // called for every frame that the button is pressed.
+            // get the delta between the click point and the current
+            // mouse position
             UIvec2 pos = uiGetCursorStartDelta();
+            // get the items layouted rectangle
             UIrect rc = uiGetRect(item);
+            // calculate our new offset and clamp
             float value = sliderstart + ((float)pos.x / (float)rc.w);
             value = (value<0)?0:(value>1)?1:value;
+            // assign the new value
             *data->progress = value;
         } break;
     }
 }
 
-int slider(UIhandle handle, const char *label, float *progress) {
+int slider(int parent, UIhandle handle, const char *label, float *progress) {
+    // create new ui item
     int item = uiItem();
+    // set persistent handle for item that is used
+    // to track activity over time
     uiSetHandle(item, handle);
+    // set size of wiget; horizontal size is dynamic, vertical is fixed
     uiSetSize(item, 0, BND_WIDGET_HEIGHT);
+    // attach our slider event handler and capture two classes of events
     uiSetHandler(item, sliderhandler, 
         UI_BUTTON0_DOWN | UI_BUTTON0_CAPTURE);
+    // store some custom data with the button that we use for styling
+    // and logic, e.g. the pointer to the data we want to alter.
     UISliderData *data = (UISliderData *)uiAllocData(item, sizeof(UISliderData));
     data->head.subtype = ST_SLIDER;
     data->label = label;
     data->progress = progress;
+    uiAppend(parent, item);
     return item;
 }
 
@@ -201,7 +250,7 @@ void radiohandler(int item, UIevent event) {
     *data->value = uiGetChildId(item);
 }
 
-int radio(UIhandle handle, int iconid, const char *label, int *value) {
+int radio(int parent, UIhandle handle, int iconid, const char *label, int *value) {
     int item = uiItem();
     uiSetHandle(item, handle);
     uiSetSize(item, label?0:BND_TOOL_WIDTH, BND_WIDGET_HEIGHT);
@@ -211,30 +260,82 @@ int radio(UIhandle handle, int iconid, const char *label, int *value) {
     data->label = label;
     data->value = value;
     uiSetHandler(item, radiohandler, UI_BUTTON0_DOWN);
+    uiAppend(parent, item);
     return item;
 }
 
-int addVList(int parent, int item) {
-    int last = uiLastChild(parent);
-    uiSetRelativeTo(item, -1, last, -1, -1);
+void columnhandler(int parent, UIevent event) {
+    int item = uiLastChild(parent);
+    int last = uiPrevSibling(item);
+    // mark the new item as positioned under the previous item
+    uiSetRelToTop(item, last);
+    // fill parent horizontally, anchor to previous item vertically
     uiSetLayout(item, UI_HFILL|UI_TOP);
-    uiSetParent(item, parent);
+    // if not the first item, add a margin of 1
     uiSetMargins(item, 0, (last < 0)?0:1, 0, 0);
+}
+
+int column(int parent) {
+    int item = uiItem();
+    uiSetHandler(item, columnhandler, UI_APPEND);
+    uiAppend(parent, item);
+    return item;
+}
+
+void vgrouphandler(int parent, UIevent event) {
+    int item = uiLastChild(parent);
+    int last = uiPrevSibling(item);
+    // mark the new item as positioned under the previous item
+    uiSetRelToTop(item, last);
+    // fill parent horizontally, anchor to previous item vertically
+    uiSetLayout(item, UI_HFILL|UI_TOP);
+    // if not the first item, add a margin
+    uiSetMargins(item, 0, (last < 0)?0:-2, 0, 0);
+}
+
+int vgroup(int parent) {
+    int item = uiItem();
+    UIData *data = (UIData *)uiAllocData(item, sizeof(UIData));
+    data->subtype = ST_COLUMN;
+    uiSetHandler(item, vgrouphandler, UI_APPEND);
+    uiAppend(parent, item);
     return item;
 }
 
-int addHGroup(int parent, int item) {
-    int last = uiLastChild(parent);
-    uiSetRelativeTo(item, last, -1, -1, -1);
-    uiSetLayout(item, UI_LEFT);
-    uiSetParent(item, parent);
+void hgrouphandler(int parent, UIevent event) {
+    int item = uiLastChild(parent);
+    int last = uiPrevSibling(item);
+    uiSetRelToLeft(item, last);
+    if (last > 0)
+        uiSetRelToRight(last, item);
+    uiSetLayout(item, UI_LEFT|UI_RIGHT);
     uiSetMargins(item, (last < 0)?0:-1, 0, 0, 0);
+}
+
+int hgroup(int parent) {
+    int item = uiItem();
+    UIData *data = (UIData *)uiAllocData(item, sizeof(UIData));
+    data->subtype = ST_ROW;
+    uiSetHandler(item, hgrouphandler, UI_APPEND);
+    uiAppend(parent, item);
     return item;
 }
 
-void demohandler(int item, UIevent event) {
-    const UIButtonData *data = (const UIButtonData *)uiGetData(item);
-    printf("clicked: %lld %s\n", uiGetHandle(item), data->label);
+void rowhandler(int parent, UIevent event) {
+    int item = uiLastChild(parent);
+    int last = uiPrevSibling(item);
+    uiSetRelToLeft(item, last);
+    if (last > 0)
+        uiSetRelToRight(last, item);
+    uiSetLayout(item, UI_LEFT|UI_RIGHT);
+    uiSetMargins(item, (last < 0)?0:8, 0, 0, 0);
+}
+
+int row(int parent) {
+    int item = uiItem();
+    uiSetHandler(item, rowhandler, UI_APPEND);
+    uiAppend(parent, item);
+    return item;
 }
 
 void draw(NVGcontext *vg, float w, float h) {
@@ -427,31 +528,28 @@ void draw(NVGcontext *vg, float w, float h) {
     
     uiClear();
     
+    int root = uiItem(); 
     // position root element
     uiSetLayout(0,UI_LEFT|UI_TOP);
     uiSetMargins(0,600,10,0,0);
     uiSetSize(0,250,400);
     
-    int c = button(1, BND_ICONID(6,3), "Item 1", demohandler);
-    uiSetParent(c, 0);
-    uiSetSize(c, 100, 100);
-    uiSetLayout(c, UI_CENTER);
-    
+    int col = column(0);
+    uiSetLayout(col, UI_TOP|UI_HFILL);
     
-    addVList(0, button(1, BND_ICONID(6,3), "Item 1", demohandler));
-    addVList(0, button(2, BND_ICONID(6,3), "Item 2", demohandler));
+    button(col, 1, BND_ICONID(6,3), "Item 1", demohandler);
+    button(col, 2, BND_ICONID(6,3), "Item 2", demohandler);
     
     static int enum1 = 0;
     
     {
-        int h = addVList(0, uiItem());
-        addHGroup(h, radio(3, BND_ICONID(6,3), "Item 3.0", &enum1));
-        addHGroup(h, radio(4, BND_ICONID(0,10), NULL, &enum1));
-        addHGroup(h, radio(5, BND_ICONID(1,10), NULL, &enum1));
-        addHGroup(h, radio(6, BND_ICONID(6,3), "Item 3.3", &enum1));
+        int h = hgroup(col);
+        radio(h, 3, BND_ICONID(6,3), "Item 3.0", &enum1);
+        radio(h, 4, BND_ICONID(0,10), NULL, &enum1);
+        radio(h, 5, BND_ICONID(1,10), NULL, &enum1);
+        radio(h, 6, BND_ICONID(6,3), "Item 3.3", &enum1);
     }
     
-    /*
     static float progress1 = 0.25f;
     static float progress2 = 0.75f;
     
@@ -470,7 +568,6 @@ void draw(NVGcontext *vg, float w, float h) {
     }
     
     button(col, 11, BND_ICONID(6,3), "Item 5", NULL);
-    */
     
     uiProcess();
     
diff --git a/oui.h b/oui.h
index 4b2347e..cd7805c 100644
--- a/oui.h
+++ b/oui.h
@@ -93,6 +93,8 @@ typedef enum UIevent {
     UI_BUTTON0_HOT_UP = 0x04,
     // item is being captured (button 0 constantly pressed)
     UI_BUTTON0_CAPTURE = 0x08,
+    // item has been added to container
+    UI_APPEND = 0x10,
 } UIevent;
 
 // handler callback; event is one of UI_EVENT_*
@@ -164,10 +166,9 @@ void uiClear();
 int uiItem();
 
 // assign an item to a container.
-// parent is the item ID of the containing item; an item ID of 0 refers to the
-// root item.
-// if item is already assigned to a parent, an assertion will be thrown.
-void uiSetParent(int item, int parent);
+// an item ID of 0 refers to the root item.
+// if child is already assigned to a parent, an assertion will be thrown.
+int uiAppend(int item, int child);
 
 // layout all added items and update the internal state according to the
 // current cursor position and button states.
@@ -203,11 +204,29 @@ int uiGetChildId(int item);
 // returns an items next sibling in the list of the parent containers children.
 // if item is 0 or the item is the last child item, -1 will be returned.
 int uiNextSibling(int item);
+// returns an items previous sibling in the list of the parent containers
+// children.
+// if item is 0 or the item is the first child item, -1 will be returned.
+int uiPrevSibling(int item);
 
 void uiSetSize(int item, int w, int h);
+int uiGetWidth(int item);
+int uiGetHeight(int item);
 void uiSetLayout(int item, int flags);
+int uiGetLayout(int item);
 void uiSetMargins(int item, int t, int r, int b, int l);
-void uiSetRelativeTo(int item, int titem, int ritem, int bitem, int litem);
+int uiGetMarginLeft(int item);
+int uiGetMarginTop(int item);
+int uiGetMarginRight(int item);
+int uiGetMarginDown(int item);
+void uiSetRelToLeft(int item, int other);
+int uiGetRelToLeft(int item);
+void uiSetRelToTop(int item, int other);
+int uiGetRelToTop(int item);
+void uiSetRelToRight(int item, int other);
+int uiGetRelToRight(int item);
+void uiSetRelToDown(int item, int other);
+int uiGetRelToDown(int item);
 
 // returns the items layout rectangle relative to the parent. If uiGetRect()
 // is called before uiProcess(), the values of the returned rectangle are
@@ -293,6 +312,8 @@ typedef struct UIitem {
     int kidid;
     // index of next sibling with same parent
     int nextitem;
+    // index of previous sibling with same parent
+    int previtem;
     
     // one or multiple of UIlayoutFlags
     int layout_flags;
@@ -303,6 +324,9 @@ typedef struct UIitem {
     int margins[4];
     // neighbors to position borders to
     int relto[4];
+    
+    // computed size
+    UIvec2 computed_size;
     // relative rect
     UIrect rect;
     
@@ -439,20 +463,10 @@ UIitem *uiItemPtr(int item) {
 
 void uiClear() {
     assert(ui_context);
-    ui_context->count = 1;
+    ui_context->count = 0;
     ui_context->datasize = 0;
     ui_context->hot_item = -1;
     ui_context->active_item = -1;
-
-    // init root object    
-    UIitem *item = ui_context->items;
-    memset(item, 0, sizeof(UIitem));
-    item->parent = -1;
-    item->firstkid = -1;
-    item->lastkid = -1;
-    item->nextitem = -1;
-    
-    item->data = -1;
 }
 
 int uiItem() {
@@ -464,26 +478,37 @@ int uiItem() {
     item->firstkid = -1;
     item->lastkid = -1;
     item->nextitem = -1;
+    item->previtem = -1;
     item->data = -1;
     for (int i = 0; i < 4; ++i)
         item->relto[i] = -1;
     return idx;
 }
 
-void uiSetParent(int item, int parent) {
-    assert(item > 0);
-    assert(uiParent(item) == -1);
+void uiNotifyItem(int item, UIevent event) {
     UIitem *pitem = uiItemPtr(item);
-    UIitem *pparent = uiItemPtr(parent);
-    pitem->parent = parent;
+    if (pitem->handler && (pitem->event_flags & event)) {
+        pitem->handler(item, event);
+    }
+}
+
+int uiAppend(int item, int child) {
+    assert(child > 0);
+    assert(uiParent(child) == -1);
+    UIitem *pitem = uiItemPtr(child);
+    UIitem *pparent = uiItemPtr(item);
+    pitem->parent = item;
     pitem->kidid = pparent->numkids++;
     if (pparent->lastkid < 0) {
-        pparent->firstkid = item;
-        pparent->lastkid = item;
+        pparent->firstkid = child;
+        pparent->lastkid = child;
     } else {
-        uiItemPtr(pparent->lastkid)->nextitem = item;
-        pparent->lastkid = item;
+        pitem->previtem = pparent->lastkid;
+        uiItemPtr(pparent->lastkid)->nextitem = child;
+        pparent->lastkid = child;
     }
+    uiNotifyItem(item, UI_APPEND);
+    return child;
 }
 
 void uiSetSize(int item, int w, int h) {
@@ -492,9 +517,20 @@ void uiSetSize(int item, int w, int h) {
     pitem->size.y = h;
 }
 
+int uiGetWidth(int item) {
+    return uiItemPtr(item)->size.x;
+}
+
+int uiGetHeight(int item) {
+    return uiItemPtr(item)->size.y;
+}
+
 void uiSetLayout(int item, int flags) {
-    UIitem *pitem = uiItemPtr(item);
-    pitem->layout_flags = flags;
+    uiItemPtr(item)->layout_flags = flags;
+}
+
+int uiGetLayout(int item) {
+    return uiItemPtr(item)->layout_flags;
 }
 
 void uiSetMargins(int item, int l, int t, int r, int b) {
@@ -505,14 +541,54 @@ void uiSetMargins(int item, int l, int t, int r, int b) {
     pitem->margins[3] = b;
 }
 
-void uiSetRelativeTo(int item, int litem, int titem, int ritem, int bitem) {
-    UIitem *pitem = uiItemPtr(item);
-    pitem->relto[0] = litem;
-    pitem->relto[1] = titem;
-    pitem->relto[2] = ritem;
-    pitem->relto[3] = bitem;
+int uiGetMarginLeft(int item) {
+    return uiItemPtr(item)->margins[0];
+}
+int uiGetMarginTop(int item) {
+    return uiItemPtr(item)->margins[1];
+}
+int uiGetMarginRight(int item) {
+    return uiItemPtr(item)->margins[2];
+}
+int uiGetMarginDown(int item) {
+    return uiItemPtr(item)->margins[3];
+}
+
+
+void uiSetRelToLeft(int item, int other) {
+    assert((other < 0) || (uiParent(other) == uiParent(item)));
+    uiItemPtr(item)->relto[0] = other;
+}
+
+int uiGetRelToLeft(int item) {
+    return uiItemPtr(item)->relto[0];
 }
 
+void uiSetRelToTop(int item, int other) {
+    assert((other < 0) || (uiParent(other) == uiParent(item)));
+    uiItemPtr(item)->relto[1] = other;
+}
+int uiGetRelToTop(int item) {
+    return uiItemPtr(item)->relto[1];
+}
+
+void uiSetRelToRight(int item, int other) {
+    assert((other < 0) || (uiParent(other) == uiParent(item)));
+    uiItemPtr(item)->relto[2] = other;
+}
+int uiGetRelToRight(int item) {
+    return uiItemPtr(item)->relto[2];
+}
+
+void uiSetRelToDown(int item, int other) {
+    assert((other < 0) || (uiParent(other) == uiParent(item)));
+    uiItemPtr(item)->relto[3] = other;
+}
+int uiGetRelToDown(int item) {
+    return uiItemPtr(item)->relto[3];
+}
+
+
 UI_INLINE int uiComputeChainSize(UIitem *pkid, int dim) {
     UIitem *pitem = pkid;
     int wdim = dim+2;
@@ -560,6 +636,7 @@ UI_INLINE void uiComputeSizeDim(UIitem *pitem, int dim) {
         }
     
         pitem->rect.v[wdim] = size;
+        pitem->computed_size.v[dim] = size;
     }
 }
 
@@ -577,28 +654,35 @@ static void uiComputeBestSize(int item) {
     uiComputeSizeDim(pitem, 1);
 }
 
-static void uiLayoutChildItem(UIitem *pparent, UIitem *pitem, int dim) {
+static void uiLayoutChildItem(UIitem *pparent, UIitem *pitem, int *dyncount, int dim) {
     if (pitem->visited & (4<<dim)) return;
     pitem->visited |= (4<<dim);
     
+    if (!pitem->size.v[dim]) {
+        *dyncount = (*dyncount)+1;
+    }
+    
     int wdim = dim+2;
     
     int wl = 0;
     int wr = pparent->rect.v[wdim];
     
     int flags = pitem->layout_flags>>dim;
-    if ((flags & UI_LEFT) && (pitem->relto[dim] > 0)) {
+    int hasl = (flags & UI_LEFT) && (pitem->relto[dim] > 0);
+    int hasr = (flags & UI_RIGHT) && (pitem->relto[wdim] > 0);
+    
+    if (hasl) {
         UIitem *pl = uiItemPtr(pitem->relto[dim]);
-        uiLayoutChildItem(pparent, pl, dim);
-        wl = pl->rect.v[dim]+pl->rect.v[wdim];
+        uiLayoutChildItem(pparent, pl, dyncount, dim);
+        wl = pl->rect.v[dim]+pl->rect.v[wdim]+pl->margins[wdim];
         wr -= wl;
     }
-    if ((flags & UI_RIGHT) && (pitem->relto[wdim] > 0)) {
+    if (hasr) {
         UIitem *pl = uiItemPtr(pitem->relto[wdim]);
-        uiLayoutChildItem(pparent, pl, dim);
-        wr = pl->rect.v[dim]-wl;
+        uiLayoutChildItem(pparent, pl, dyncount, dim);
+        wr = pl->rect.v[dim]-pl->margins[dim]-wl;
     }
-    
+
     switch(flags & UI_HFILL) {
     default:
     case UI_HCENTER: {
@@ -611,8 +695,28 @@ static void uiLayoutChildItem(UIitem *pparent, UIitem *pitem, int dim) {
         pitem->rect.v[dim] = wl+wr-pitem->rect.v[wdim]-pitem->margins[wdim];
     } break;
     case UI_HFILL: {
-        pitem->rect.v[dim] = wl+pitem->margins[dim];
-        pitem->rect.v[wdim] = wr-pitem->margins[dim]-pitem->margins[wdim];
+        if (pitem->size.v[dim]) { // hard maximum size; can't stretch
+            if (hasl)
+                pitem->rect.v[dim] = wl+wr-pitem->rect.v[wdim]-pitem->margins[wdim];
+            else
+                pitem->rect.v[dim] = wl+pitem->margins[dim];
+        } else {
+            if (1) { //!pitem->rect.v[wdim]) {
+                int width = (pparent->rect.v[wdim] - pparent->computed_size.v[dim]);
+                int space = width / (*dyncount);
+                //int rest = width - space*(*dyncount);
+                if (!hasl) {
+                    pitem->rect.v[dim] = wl+pitem->margins[dim];
+                    pitem->rect.v[wdim] = wr-pitem->margins[dim]-pitem->margins[wdim];
+                } else {
+                    pitem->rect.v[wdim] = space-pitem->margins[dim]-pitem->margins[wdim];
+                    pitem->rect.v[dim] = wl+wr-pitem->rect.v[wdim]-pitem->margins[wdim];
+                }
+            } else {
+                pitem->rect.v[dim] = wl+pitem->margins[dim];
+                pitem->rect.v[wdim] = wr-pitem->margins[dim]-pitem->margins[wdim];
+            }
+        }
     } break;
     }    
 }
@@ -621,7 +725,8 @@ UI_INLINE void uiLayoutItemDim(UIitem *pitem, int dim) {
     int kid = pitem->firstkid;
     while (kid > 0) {
         UIitem *pkid = uiItemPtr(kid);
-        uiLayoutChildItem(pitem, pkid, dim);
+        int dyncount = 0;
+        uiLayoutChildItem(pitem, pkid, &dyncount, dim);
         kid = uiNextSibling(kid);
     }
 }
@@ -655,6 +760,10 @@ int uiNextSibling(int item) {
     return uiItemPtr(item)->nextitem;
 }
 
+int uiPrevSibling(int item) {
+    return uiItemPtr(item)->previtem;
+}
+
 int uiParent(int item) {
     return uiItemPtr(item)->parent;
 }
@@ -730,14 +839,8 @@ int uiFindItem(int item, int x, int y) {
     return -1;
 }
 
-void uiNotifyItem(int item, UIevent event) {
-    UIitem *pitem = uiItemPtr(item);
-    if (pitem->handler && (pitem->event_flags & event)) {
-        pitem->handler(item, event);
-    }
-}
-
 void uiProcess() {
+    if (!ui_context->count) return;
     uiComputeBestSize(0);
     // position root element rect
     uiItemPtr(0)->rect.x = uiItemPtr(0)->margins[0];