LabWindows/CVI虚拟仪器设计技术场景与游戏设计之：时钟制作

3：程序注释

①设置透明背景在程序中，采用了SetCtrlAttribute 函数的VAL_TRANSPARENT 属性将Text Message 控件的背景设置为透明。对于12 个数字标签，需要重复设置VAL_TRANSPARENT ，其代码为：

SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_1, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_2, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_3, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_4, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_5, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_6, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_7, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_8, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_9, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_10, ATTR_TEXT_BGCOLOR,VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_11, ATTR_TEXT_BGCOLOR,VAL_TRANSPARENT);
SetCtrlAttribute (panelHandle, PANEL_TEXTMSG_12, ATTR_TEXT_BGCOLOR,VAL_TRANSPARENT);

但是，这种设置方式重复工作量较大，代码大量冗余，容易出现错误，可以采用循环结构优化代码设计，即主函数中使用的代码：

for (i = 2; i < 14; i ++)
{
SetCtrlAttribute (panelHandle, i, ATTR_TEXT_BGCOLOR, VAL_TRANSPARENT);
}

采用此种代码方式，需要控制每个Text Message 控件的Tab Order 属性，使自动生成的"时钟制作.h"文件控件常量值遵从一定顺序，即：

#include <userint.h>

#ifdef __cplusplus

extern "C" {

#endif

#define

PANEL

1

#define

PANEL_TEXTMSG_1

2

#define

PANEL_TEXTMSG_2

3

#define

PANEL_TEXTMSG_3

4

#define

PANEL_TEXTMSG_4

5

#define

PANEL_TEXTMSG_5

6

#define

PANEL_TEXTMSG_6

7

#define

PANEL_TEXTMSG_7

8

#define

PANEL_TEXTMSG_8

9

#define

PANEL_TEXTMSG_9

10

#define

PANEL_TEXTMSG_10

11

#define

PANEL_TEXTMSG_11

12

#define

PANEL_TEXTMSG_12

13

#define

PANEL_CANVAS

14

#define

PANEL_TIMER

15

#define

PANEL_DECORATION

16

int CVICALLBACK PanelCB(int panel, int event, void *callbackData, int eventData1, int eventData2); 

int CVICALLBACK timer(int panel, int control, int event, void *callbackData, int eventData1, int eventData2); #ifdef __cplusplus

 } 

#endif