I like to make a habit of creating my variables with an initial value. When I first started using lists, it drove me up the wall that sometimes my list variables simply would not store the information I was trying to put into them. The reason for this is that, in most cases, linear lists must be set to "[]" (no quotes), and property lists must be set to "[:]", before they will store list information.
Now, I make sure that when I create a variable that I want to use as a list, I type in "[]" or "[:]" as its initial value, depending on the type of list it is supposed to be. I also make sure to enter a description of each variable as it is created. Sometimes I click through a little too fast, and so the Initial Value and Description for a new variable will be left at the default. This is easy to change in those fields in the Variables window.
Another type of variable I like to set an initial value for is icon variables. Sometimes I want to create a Display Icon that usually will appear right where I positioned it on screen, but I also want the optional ability to position it with a variable..
To handle this situation, I create icon-level variables, such as PosX@"my icon" and PosY@"my Icon". I use these in the InitialX and InitialY fields in the Icon's Layout tab, making sure to write down what the original values were.
When I close the Icon Properties Dialogue for the icon, Authorware will prompt me to create those icon variables. I set their initial values to the InitialX and InitialY that were originally in the fields. This creates an icon that can be variably positioned, but unless I change those variables, it is positioned exactly where I first dragged it.
A nice side benefit is that if I change these
variables to display the icon at a new position,
I can change them back with the Initialize()
function.
