Fix 652 (#656)

* fix: #654

* fix: #652

Author: 3lang3

packages/react-vant/src/components/picker/PickerColumn.tsx

@@ -98,7 +98,7 @@ const PickerColumn = memo<
       index = adjustIndex(index) || 0
       const offset = -index * props.itemHeight
       const trigger = () => {
-        if (options[index][valueKey] !== value) {
+        if (options[index]?.[valueKey] !== value) {
           onSelect(options[index])
         }
       }

packages/react-vant/src/components/picker/columnsExtend.tsx

@@ -16,6 +16,10 @@ type KeysProps = {
 function useColumnsFn(options: PickerProps['columns'], keys: KeysProps) {
   const { textKey, valueKey, childrenKey } = keys
   const dataType = useMemo(() => {
+    const isCascade = options.some(
+      el => typeof el === 'object' && childrenKey in el
+    )
+    if (isCascade) return 'cascade'
     const firstColumn = options[0] || {}
 
     if (typeof firstColumn === 'object') {