各位高手，小弟移植了ucgui到奋斗STM32单片机开发板上，编写测试程序，添加了几个按钮。测试发现，按钮一直在闪烁。请教其中的原因，谢谢！

测试程序呢?

这是界面显示部分的代码：
void Fun(void) {
 unsigned short i=0,a;
 //open_f=0;
 GUI_CURSOR_Show();
 WM_SetCreateFlags(WM_CF_MEMDEV);       /* Automatically use memory devices on all windows */  
 DesktopColorOld = WM_SetDesktopColor(GUI_BLUE);  /* Automatically update desktop window */
 /* 建立窗体，包含了资源列表，资源数目， 并指定回调函数 */  
 //hWin = GUI_CreateDialogBox(aDialogCreate, GUI_COUNTOF(aDialogCreate), _cbCallback, 0, 0, 0);
 hWin = GUI_CreateDialogBox(aDialogCreate, GUI_COUNTOF(aDialogCreate), NULL, 0, 0, 0);
 /* 设置窗体字体 */
 FRAMEWIN_SetFont(hWin, pFont);
 /* 获得TEXT 部件的句柄 */
 text0 = WM_GetDialogItem(hWin, GUI_ID_TEXT0);
 text1 = WM_GetDialogItem(hWin, GUI_ID_TEXT1);
 /* 获得slider 部件的句柄 */
 slider0 = WM_GetDialogItem(hWin, GUI_ID_SLIDER0);
 /* 获得按钮 部件的句柄 */
 _ahButton[0] = WM_GetDialogItem(hWin, GUI_ID_BUTTON0);
 _ahButton[1] = WM_GetDialogItem(hWin, GUI_ID_BUTTON1);
 _ahButton[2] = WM_GetDialogItem(hWin, GUI_ID_BUTTON2);
 _ahButton[3] = WM_GetDialogItem(hWin, GUI_ID_BUTTON3);
 _ahButton[4] = WM_GetDialogItem(hWin, GUI_ID_BUTTON4);
 
 //按键字体设置
 BUTTON_SetFont(_ahButton[0],pFont);
 BUTTON_SetFont(_ahButton[1],pFont);
 BUTTON_SetFont(_ahButton[2],pFont);
 BUTTON_SetFont(_ahButton[3],pFont);
 BUTTON_SetFont(_ahButton[4],pFont);
 //按键背景色设置
 BUTTON_SetBkColor(_ahButton[0],0,GUI_GRAY);     //按键背景颜色
 BUTTON_SetBkColor(_ahButton[1],0,GUI_GRAY);  
 BUTTON_SetBkColor(_ahButton[2],0,GUI_GRAY);  
 BUTTON_SetBkColor(_ahButton[3],0,GUI_GRAY);  
 BUTTON_SetBkColor(_ahButton[4],0,GUI_GRAY);  
 
 //按键前景色设置
 BUTTON_SetTextColor(_ahButton[0],0,GUI_WHITE);
 BUTTON_SetTextColor(_ahButton[1],0,GUI_WHITE);
 BUTTON_SetTextColor(_ahButton[2],0,GUI_WHITE);
 BUTTON_SetTextColor(_ahButton[3],0,GUI_WHITE);
 BUTTON_SetTextColor(_ahButton[4],0,GUI_WHITE);    
 listbox1 = WM_GetDialogItem(hWin, GUI_ID_LISTBOX0); //获得对话框里GUI_ID_LISTBOX0项目的句柄  
 LISTBOX_SetFont(listbox1,pFont); //设置对话框里列表框的字体
 SCROLLBAR_CreateAttached(listbox1, SCROLLBAR_CF_VERTICAL); //设置对话框里列表框-卷动方向为下拉
 BUTTON_SetBkColor(_ahButton[0],0,GUI_WHITE);    //设置对话框里按键CLEAR未被按下的字体颜色
 BUTTON_SetBkColor(_ahButton[1],0,GUI_WHITE);    //设置对话框里按键CLEAR未被按下的字体颜色
 BUTTON_SetBkColor(_ahButton[2],0,GUI_WHITE);    //设置对话框里按键CLEAR未被按下的字体颜色
 BUTTON_SetBkColor(_ahButton[3],0,GUI_WHITE);    //设置对话框里按键CLEAR未被按下的字体颜色
 BUTTON_SetBkColor(_ahButton[4],0,GUI_WHITE);    //设置对话框里按键CLEAR未被按下的字体颜色
 
 /* 将SD卡根目录下的MP3文件增加到列表框里 */
 //a=file_num;
 //while(a>0){
 // LISTBOX_AddString(listbox1,str[i]);
 // i++;
// a--;
 //}
 while (1)
 {
  // #if 0
//if(open_f==0){
  BUTTON_SetBMPEx(_ahButton[0],BUTTON_BI_UNPRESSED,&play_bt,29,3);/*为按钮设置图片，图片数据为play_bt，图片相对于按钮的坐标为（29,3）*/
BUTTON_SetBMPEx(_ahButton[1],BUTTON_BI_UNPRESSED,&prev_bt,29,3);
BUTTON_SetBMPEx(_ahButton[2],BUTTON_BI_UNPRESSED,&next_bt,29,3);
BUTTON_SetBMPEx(_ahButton[3],BUTTON_BI_UNPRESSED,&bk_bt,29,3);
BUTTON_SetBMPEx(_ahButton[4],BUTTON_BI_UNPRESSED,&bk_bt,29,3);
//}
#if 0
else if(open_f==1){
BUTTON_SetBMPEx(_ahButton[0],BUTTON_BI_UNPRESSED,&pause_bt,29,3);
BUTTON_SetBMPEx(_ahButton[1],BUTTON_BI_UNPRESSED,&prev_bt,29,3);
BUTTON_SetBMPEx(_ahButton[2],BUTTON_BI_UNPRESSED,&next_bt,29,3);
BUTTON_SetBMPEx(_ahButton[3],BUTTON_BI_UNPRESSED,&stop_bt,29,3);
BUTTON_SetBMPEx(_ahButton[4],BUTTON_BI_UNPRESSED,&fast_bt,29,3);
}
else if(open_f==2){
BUTTON_SetBMPEx(_ahButton[0],BUTTON_BI_UNPRESSED,&play_bt,29,3);
BUTTON_SetBMPEx(_ahButton[1],BUTTON_BI_UNPRESSED,&bk_bt,29,3);
BUTTON_SetBMPEx(_ahButton[2],BUTTON_BI_UNPRESSED,&bk_bt,29,3);
BUTTON_SetBMPEx(_ahButton[3],BUTTON_BI_UNPRESSED,&stop_bt,29,3);
BUTTON_SetBMPEx(_ahButton[4],BUTTON_BI_UNPRESSED,&bk_bt,29,3);
}
#endif
//OSTimeDlyHMSM(0, 0, 0, 100);  //延时
//SLIDER_SetValue(slider0,mp3_step);  //播放进度条刷新
WM_Exec();  //显示刷新

 }
}