表单设计器

frontend/src/components/FormDesigner/Designer.tsx

@@ -37,7 +37,6 @@ import {
   useSensor, 
   useSensors,
   pointerWithin,
-  rectIntersection,
   closestCenter
 } from '@dnd-kit/core';
 import { arrayMove } from '@dnd-kit/sortable';
@@ -135,35 +134,84 @@ const FormDesigner: React.FC<FormDesignerProps> = ({
     })
   );
 
-  // 自定义碰撞检测策略：优先使用指针检测，避免栅格内部区域干扰排序
+  // 自定义碰撞检测策略：基于边界判断，区分"插入"和"拖入"
   const customCollisionDetection = useCallback((args: any) => {
-    // 首先尝试使用 pointerWithin - 只有指针真正进入区域时才触发
     const pointerCollisions = pointerWithin(args);
     
-    if (pointerCollisions.length > 0) {
-      // 过滤掉栅格列（grid-xxx-col-xxx），优先选择画布或字段
-      const nonGridCollisions = pointerCollisions.filter((collision: any) => {
-        const id = collision.id.toString();
-        return !id.startsWith('grid-') || id === 'canvas' || id === 'canvas-bottom';
-      });
-      
-      if (nonGridCollisions.length > 0) {
-        return nonGridCollisions;
+    if (pointerCollisions.length === 0) {
+      return closestCenter(args);
+    }
+
+    // 查找栅格字段的碰撞
+    const gridFieldCollisions = pointerCollisions.filter((collision: any) => {
+      const fieldId = collision.id.toString();
+      return fields.some(f => f.id === fieldId && f.type === 'grid');
+    });
+
+    // 如果拖到栅格字段上，使用边界检测
+    if (gridFieldCollisions.length > 0 && args.pointerCoordinates) {
+      const gridCollision = gridFieldCollisions[0];
+      const droppableContainer = args.droppableContainers.find(
+        (container: any) => container.id === gridCollision.id
+      );
+
+      if (droppableContainer?.rect?.current) {
+        const rect = droppableContainer.rect.current;
+        const pointer = args.pointerCoordinates;
+        
+        // 计算鼠标在栅格字段中的相对垂直位置（0-1）
+        const relativeY = (pointer.y - rect.top) / rect.height;
+        
+        // 边缘阈值：上下各 20%
+        const edgeThreshold = 0.2;
+        
+        if (relativeY < edgeThreshold || relativeY > (1 - edgeThreshold)) {
+          // 在边缘区域 → 返回栅格字段本身（插入到栅格前后）
+          return [gridCollision];
+        } else {
+          // 在中心区域 → 查找栅格列（拖入栅格内部）
+          const gridColumnCollisions = pointerCollisions.filter((collision: any) => {
+            const id = collision.id.toString();
+            return id.startsWith('grid-') && id.includes('-col-');
+          });
+          
+          if (gridColumnCollisions.length > 0) {
+            return gridColumnCollisions;
+          }
+        }
       }
-      
-      // 如果只有栅格列，说明确实是要拖入栅格
-      return pointerCollisions;
     }
-    
-    // 如果 pointerWithin 没有结果，使用 rectIntersection 作为后备
-    const rectCollisions = rectIntersection(args);
-    if (rectCollisions.length > 0) {
-      return rectCollisions;
+
+    // 非栅格字段：优先级排序
+    // 1. 优先选择非栅格字段
+    const nonGridFields = pointerCollisions.filter((collision: any) => {
+      const id = collision.id.toString();
+      return id.startsWith('field_') && !fields.some(f => f.id === id && f.type === 'grid');
+    });
+    if (nonGridFields.length > 0) {
+      return nonGridFields;
     }
-    
-    // 最后使用 closestCenter 作为兜底
-    return closestCenter(args);
-  }, []);
+
+    // 2. 画布或底部区域
+    const canvasCollisions = pointerCollisions.filter((collision: any) => {
+      const id = collision.id.toString();
+      return id === 'canvas' || id === 'canvas-bottom';
+    });
+    if (canvasCollisions.length > 0) {
+      return canvasCollisions;
+    }
+
+    // 3. 栅格列
+    const gridColumns = pointerCollisions.filter((collision: any) => {
+      const id = collision.id.toString();
+      return id.startsWith('grid-') && id.includes('-col-');
+    });
+    if (gridColumns.length > 0) {
+      return gridColumns;
+    }
+
+    return pointerCollisions;
+  }, [fields]);
 
   // 生成唯一 ID
   const generateId = () => `field_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;

frontend/src/components/FormDesigner/components/DesignCanvas.tsx

@@ -96,9 +96,12 @@ const DesignCanvas: React.FC<DesignCanvasProps> = ({
             <div className="form-designer-field-list">
               {fields.map((field) => (
                 <React.Fragment key={field.id}>
-                  {/* 插入指示器 - 显示在拖拽悬停的字段上方 */}
-                  {activeId && overId === field.id && activeId !== field.id && (
-                    <DropIndicator text="释放以插入到此处" />
+                  {/* 插入指示器 - 显示在字段上方（栅格字段会根据边界自动判断） */}
+                  {activeId && 
+                   overId === field.id && 
+                   activeId !== field.id && 
+                   !overId?.toString().includes('-col-') && (
+                    <DropIndicator text={field.type === 'grid' ? "释放以插入到栅格前/后" : "释放以插入到此处"} />
                   )}
                   
                   <FieldItem