欢迎进入Oracle社区论坛,与200万技术人员互动交流 >>进入 由于工作关系,笔者常常接触微软的数据库开发工具VFP,并用于开发一些常见的应用系统,其中,编制功能完善的选单栏是VFP应用开发中最常见的任务之一。 功能完善的选单栏是系统界面的重要组成部分,
欢迎进入Oracle社区论坛,与200万技术人员互动交流 >>进入
由于工作关系,笔者常常接触微软的数据库开发工具VFP,并用于开发一些常见的应用系统,其中,编制功能完善的选单栏是VFP应用开发中最常见的任务之一。
功能完善的选单栏是系统界面的重要组成部分,是应用程序设计是否友好的一个重要体现。
编辑选单中常见的问题有:设置访问键、分隔符、快捷键、标记、失效状态等。
下面笔者将介绍它们在VFP中的实现方法。
1.给选单定义访问键
访问键可使系统使用者用键盘操作选单中的命令。
要想给选单添加访问键,在选单编辑过程中给选单名称后加“(<F)”就可以了,注意“F”是根据需要填写的。
2.给选单命令定义快捷键及添加提示信息
快捷键可完善选单的功能,提高系统操作时的速度。提示信息使得系统使用人员更快地了解选单功能。
要想给选单项定义,可在选单编辑过程中,单击“选项”下的按钮,将弹出对话框,在提示处按下要定义的键就可以了。要添加提示信息则在其中的“信息(G):”右侧的框中填入要提示的信息并用字符串引号引起来即可。
3.给选项打或去掉“√”标记
mrkbar()是判断选单是否被打标记的一个函数,若已选返回值为真,否则为假。配合使用命令setmarkof可把选单项打上或去掉标记。
例如下面一段命令加在选单过程里面就可给打上或去掉“√”标记:
if!mrkbar("文件f",3)
setmarkofbar2of文件fto.t.
命令
else
setmarkofbar2of文件fto.f.
命令
endif
4.给选单加分隔符
分隔线可增强选单的可读性,要想实现加分隔线的效果,只要在选单编辑过程中给“选单名称”项中加入“-”符号即可。
5.让某一个选单标题或选项暂时失效并恢复
在程序运行过程中有时需要让某一个选单暂时失效,失效后需要时还能恢复,实现方法有两种:
(1)使用命令setskipof
例如,使图1中“文件”选单标题暂时失效的命令为:
setskipofpopup文件f.t.
恢复命令为:
setskipofpopup文件f.f.
使图1中“文件”下的第二项暂时失效的命令为:
setskipofbar2of文件f.t.
恢复命令为:
setskipofbar2of文件f.f.
(2)使用命令releasepopup
图1.普通选单各部分名称
例如,要使图1中“文件”选单暂时失效,可使用命令:
releasepopup文件f
想恢复失效的选单,再调用一次就可以了,例如选单文件名为cd1.mpx,使用命令:
docd1.mpx
6.给选单添加系统选单选项
图2.选单设计器
在VFP6.0中有许多现成的系统选单选项供开发者选用,使用它们可丰富选单的功能,从而完善系统的功能。
图3.选单选项的快捷键设置
添加方法是在选单编辑时单击“插入栏…”按钮,就会弹出图4所示的对话框,在其中选择需要的系统选单选项即可。
图4.系统选单选项

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