PC仿真emwin的下拉框，点击无下拉

xianghuafen

pc仿真emwin的下拉框程序，和视频教程里一样，但是点击下拉框就是不下拉，不知道怎么办？？？
#include "GUI.h"
#include "DIALOG.h"
//#include "DROPDOWN.h"
void emwin_demo(void);
void MainTask(void)
{
    GUI_Init();
    emwin_demo();
    while (1);
}
extern GUI_CONST_STORAGE GUI_FONT GUI_Fontsong21;
void emwin_demo(void)
{

    DROPDOWN_Handle DropDown;
    DropDown=DROPDOWN_CreateEx(5, 5, 60, 40, WM_HBKWIN, WM_CF_SHOW, DROPDOWN_CF_AUTOSCROLLBAR, GUI_ID_DROPDOWN0);
    DROPDOWN_AddString(DropDown,"10");
    DROPDOWN_AddString(DropDown,"17");
    DROPDOWN_AddString(DropDown,"30");
    DROPDOWN_SetAutoScroll(DropDown, 1);
    GUI_Delay(10);
}

xianghuafen

搞定了，要在while(1)中调用GUI_Exec();