On the subject of screen size.. article 1 of 2

[swatts]

Howdy Pardners,

Hope your wiring is going well!

LabVIEW can be quite cumbersome when dealing with screen sizes, our stock way of dealing with this is to restrict the screen size of our applications. This hasn't been too much of an issue until now. My current project needs to be able to run on different resolutions and it also needs to undock graphs, these also need to be resizeable. I thought it may be useful to list out the techniques and challenges.

First lets think about what we want to happen when a screen size is changed.

• We want some controls to change in proportion to the screen size, graphs for example.
• We want some controls to stay the same size but be anchored to a position on the screen, buttons and drop down controls.
• We want some controls to stay in proportion to one axis, so a list box to adjust vertically, a status string to adjust horizontally.
• Some controls can be removed (tip: the easiest to manage control is one you don't need to manage!).
• Some controls can be restricted.

First let's deal with undocking.....

The first challenge here is to make a button that keeps its proportions, and is locked to a position on the graph. I want it to always be in the top right hand corner of the graph. Aesthetically I want it to be unobtrusive (i.e. use transparency to make sure it doesn't get in the way of the graph). I made a line drawing in LibreOffice Present and cut and paste this into a vertical button (from the UI Control Suite:System Controls Palette). The easiest way to restrict its size is to set it as a Strict Type Def. Finally we need to lock it into the top-right hand corner of the graph, sadly the only way to do this is writing code!

x1Undock is the button, so we take the width and move it relative to the Right of the Plot Bounds of the graph.

This is code worth noting as you'll be using it a fair bit, due to the fact that LabVIEW is natively a little random when left to its own devices!

Pressing this button will instantiate a graphscreen.vi instance, pre-loaded with the settings from the docked graph.

The code to instantiate the graph is as follows

Keeping control of all the dynamic references in this manner has worked out nice, it allows us easy housekeeping and access to control and indicator values.

Here's a link to Sam Sharps  article on a similar subject

The next article will discuss the undocked graph and give some more design pointers.

Lots of Love

Steve