Sunday, May 24, 2009

Alignment Grid & Pull-Down Menus in LabVIEW

Alignment Grid

you probably noticed the grid lines on the VI's front panel and how the waveform chart and stop controls "snap" to the grid lines as you move them around with the mouse. This feature is very useful for keeping your front panel objects aligned. If you do not like this feature, you can turn it off in the LabVIEW Options dialog. (Figures 30 and 31 show a VI front panel with the alignment grid feature turned ON and OFF, respectively.) Open the options dialog by selecting Tools, Options. . . from the menu. Navigate to the Alignment Grid category. From here, you can choose to show or hide the grid lines and to enable or disable grid alignment. If you are not sure of your preference, leave the alignment grid onyou'll probably like it.


Figure 30. VI with alignment grid option ON



Figure 31. VI with alignment grid option OFF

Pull-Down Menus

Keep in mind that LabVIEW's capabilities are many and varied. This tutorial by no means provides an exhaustive list of all of LabVIEW's ins and outs (it would be several thousand pages long if that were the case); instead, we try to get you up to speed comfortably and give you an overview of what you can do. If you want to know everything there is to know about a subject, we'd recommend looking it up in one of LabVIEW's many manuals, attending a seminar, or going to ni.com/labview on the Web. Feel free to skim through this section and some of the subsequent ones, but remember that they're here if you need a reference.

LabVIEW has two main types of menus: pull-down and pop-up. You used some of them in the last activity, and you will use both extensively in all of your program development henceforth. Now you will learn more about what they can do. We'll cover pull-down menu items very briefly in this section. You might find it helpful to look through the menus on your computer as we explain them, and maybe experiment a little.

The menu bar at the top of a VI window contains several pull-down menus (in Mac OS X, the menu bar will be at the top of the screen, consistent with other Mac OS X applications). When you click on a menu bar item, a menu appears below the bar. The pull-down menus contain items common to many applications, such as Open, Save, Copy, and Paste, and many other functions particular to LabVIEW. We'll discuss some basic pull-down menu functions here. You'll learn more about the advanced capabilities later.

Many menus also list shortcut keyboard combinations for you to use if you choose. To use keyboard shortcuts, press the appropriate key in conjunction with the control key on PCs, the command key on Macs, and the meta key on Linux.

File Menu

Pull down the File menu , which contains commands common to many applications, such as Save and Print. You can also create new VIs or open existing ones from the File menu. In addition, you can show VI Properties information and development history from this menu.



Edit Menu

Take a look at the Edit menu (see Figure 33). It has some universal commands, like Undo, Cut, Copy, and Paste, that let you edit your window. You can also search for objects with the Find and Replace . . . command and remove bad wires from the block diagram.


Figure 33. Edit menu

View Menu

In the View menu (see Figure 34), you will see options for opening the Controls Palette, Functions Palette, and Tools Palette if you've closed them. You can also show the error list and see a VI's hierarchy. The Browse Relationships submenu contains features to simplify navigation among large sets of VIs, such as determining all of a VI's subVIs and where a VI is used as a subVI.



Project Menu

The Project menu (see Figure 35) allows you to open a LabVIEW project or create a new project, as well as operate on the project to which the active VI belongs. If the active VI does not belong to any LabVIEW project, only the Open Project and New Project menu items will be enabled.



Operate Menu

You can run or stop your program from the Operate menu (see Figure 36), although you'll usually use Toolbar buttons. You can also change a VI's default values, control "print and log at completion" features, and switch between run mode and edit mode.


Figure 36. Operate menu

Tools Menu

The Tools menu (see Figure 37) lets you access built-in and add-on tools and utilities that work with LabVIEW, such as the Measurement & Automation Explorer, where you configure your DAQ devices, or the Web Publishing Tool for creating HTML pages from LabVIEW. You can view and change the myriad of LabVIEW's Options


Figure 37. Tools menu

Window Menu

Pull down the Window menu (see Figure 38). Here you can toggle between the front panel and block diagram windows, "tile" both windows so you can see them at the same time, and switch between open VIs.


Figure 38. Window menu

Help Menu

You can show, hide, or lock the contents of the Context Help window using the Help menu (see Figure 39). You can also access LabVIEW's online reference information and view the About LabVIEW information window.


Figure 39. Help menu

No comments:

Post a Comment

Your IP Address