Script layout can normally execute the command, but the icon under the menu can not correctly execute the command, why, I am a beginner, please answer the master doubts!

Updated by Ilia on 22/05/2024:
Consolidated consequent messages in a single posting:

import os
import c4d

class ImportDialog(c4d.gui.GeDialog):
    BUTTON_ID_BASE = 1000

    def __init__(self):
        self.files = []  # 初始化为空列表

    def LoadFiles(self):
        startup_path = c4d.storage.GeGetStartupWritePath()
        project_dir = os.path.join(startup_path, 'library', 'scripts', 'spline load', 'projects')
        if not os.path.exists(project_dir):
            c4d.gui.MessageDialog('项目目录不存在。')
            return False

        self.files = [os.path.join(project_dir, f) for f in os.listdir(project_dir) if f.endswith('.c4d')]
        return True

    def CreateLayout(self):
        self.SetTitle("Import C4D Projects")
        if not self.LoadFiles():
            return False  # 如果加载文件失败，不创建布局
        for index, file in enumerate(self.files, start=self.BUTTON_ID_BASE):
            filename = os.path.splitext(os.path.basename(file))[0]
            self.AddButton(index, c4d.BFH_CENTER, name=filename)
        return True

global_dialog_instance = None

def main():
    global global_dialog_instance
    if global_dialog_instance is None:
        global_dialog_instance = ImportDialog()
    global_dialog_instance.Open(c4d.DLG_TYPE_ASYNC, defaultw=400, defaulth=50)

if __name__=="__main__":
    main()