优化GUI程序，加入线程池，避免翻页卡死现象发生。

data_management/utils/image_loader.py

@@ -1,40 +1,92 @@
 """
 图片加载工具
 用于从URL加载图片并转换为PIL/CTkImage格式
+优化版本:使用连接池、线程池和缓存
 """
 import io
 import requests
 from PIL import Image
 from typing import Optional
 import customtkinter as ctk
+from concurrent.futures import ThreadPoolExecutor
+from functools import lru_cache
+import threading
 
 
+# ======================== 全局资源管理 ========================
+
+# HTTP会话(连接池)
+_session = None
+_session_lock = threading.Lock()
+
+def get_session() -> requests.Session:
+    """获取全局HTTP会话(单例模式)"""
+    global _session
+    if _session is None:
+        with _session_lock:
+            if _session is None:
+                _session = requests.Session()
+                # 配置连接池
+                adapter = requests.adapters.HTTPAdapter(
+                    pool_connections=10,  # 连接池大小
+                    pool_maxsize=20,      # 最大连接数
+                    max_retries=2,        # 重试次数
+                    pool_block=False
+                )
+                _session.mount('http://', adapter)
+                _session.mount('https://', adapter)
+    return _session
+
+
+# 线程池(用于图片加载)
+_thread_pool = None
+_thread_pool_lock = threading.Lock()
+
+def get_thread_pool() -> ThreadPoolExecutor:
+    """获取全局线程池(单例模式)"""
+    global _thread_pool
+    if _thread_pool is None:
+        with _thread_pool_lock:
+            if _thread_pool is None:
+                # 限制最多同时加载10张图片
+                _thread_pool = ThreadPoolExecutor(
+                    max_workers=10,
+                    thread_name_prefix="ImageLoader"
+                )
+    return _thread_pool
+
+
+# ======================== 图片加载函数 ========================
+
 def load_image_from_url(
     url: str,
     size: tuple = (150, 150),
-    timeout: int = 10
+    timeout: int = 5  # 降低超时时间,避免长时间阻塞
 ) -> Optional[ctk.CTkImage]:
     """
-    从URL加载图片
+    从URL加载图片(使用连接池)
     
     Args:
         url: 图片URL
         size: 目标尺寸 (width, height)
-        timeout: 超时时间（秒）
+        timeout: 超时时间(秒)
     
     Returns:
-        CTkImage对象，失败返回None
+        CTkImage对象,失败返回None
     """
     try:
+        # 使用全局session(连接复用)
+        session = get_session()
+        
         # 下载图片
-        response = requests.get(url, timeout=timeout)
+        response = session.get(url, timeout=timeout)
         response.raise_for_status()
         
         # 转换为PIL Image
         image_data = io.BytesIO(response.content)
         pil_image = Image.open(image_data)
         
-        # 转换为RGB（防止RGBA等格式问题）
+        # 转换为RGB(防止RGBA等格式问题)
         if pil_image.mode != 'RGB':
             pil_image = pil_image.convert('RGB')
         
@@ -47,17 +99,24 @@ def load_image_from_url(
         
         return ctk_image
         
+    except requests.exceptions.Timeout:
+        print(f"加载图片超时: {url}")
+        return None
+    except requests.exceptions.RequestException as e:
+        print(f"网络请求失败 {url}: {e}")
+        return None
     except Exception as e:
         print(f"加载图片失败 {url}: {e}")
         return None
 
 
+@lru_cache(maxsize=100)
 def create_placeholder_image(
     size: tuple = (150, 150),
     text: str = "加载失败"
 ) -> ctk.CTkImage:
     """
-    创建占位图片
+    创建占位图片(带缓存)
     
     Args:
         size: 图片尺寸
@@ -76,3 +135,18 @@ def create_placeholder_image(
     )
     
     return ctk_image
+
+
+def cleanup_resources():
+    """清理全局资源(程序退出时调用)"""
+    global _session, _thread_pool
+    
+    # 关闭线程池
+    if _thread_pool is not None:
+        _thread_pool.shutdown(wait=False)
+        _thread_pool = None
+    
+    # 关闭HTTP会话
+    if _session is not None:
+        _session.close()
+        _session = None