添加背景页面修复应用背景图后无法应用背景颜色的问题

src/views/tools/add_background/add_background.vue

@@ -1943,6 +1943,20 @@ const applyBackgroundSilent = async () => {
     const objects = fabricCanvas.getObjects()
     if (objects.length === 0) return
     
+    // If there are multiple objects (background image exists), keep only the last one (foreground)
+    // This ensures we remove any background images before applying color
+    if (objects.length > 1) {
+      // Disable auto-rendering to prevent multiple redraws
+      fabricCanvas.renderOnAddRemove = false
+      
+      // Remove all objects except the last one (foreground image)
+      const objectsToRemove = objects.slice(0, -1)
+      objectsToRemove.forEach(obj => fabricCanvas.remove(obj))
+      
+      // Re-enable auto-rendering
+      fabricCanvas.renderOnAddRemove = true
+    }
+    
     // Set background color using fabric v7 API
     fabricCanvas.backgroundColor = backgroundColor.value
     fabricCanvas.renderAll()