Toolbars' Visibility Condition
Under some situations you may want to be able to display or hide a toolbar. For example, you could create a project with two toolbars: one which is always visible and the other that its only displayed under a specific section of your web site.

The toolbars' visibility is controlled through the state of a condition known as the "Visibility Condition".
To access this parameter, click Tools->Toolbars Editor->Advanced

The condition must be defined by the body of a function that, when evaluated, must return either true (visible) or false (hidden).

So, for example, if you add this code to the Visibility Condition of a toolbar:

return document.title.indexOf("Customers")!=-1;

The toolbar will remain hidden unless the title of the document being displayed contains the "Customers" string in its title.
If you need to match the exact title of an HTML document to determine the visibility state of a toolbar you could use this code:

return document.title == "Ink Cartridges - Color";

In this case, the toolbar will remain hidden unless the title of an HTML document exactly matches the "Ink Cartridges - Color" string.

These are just some basic examples that take advantage of the page title to determine the visibility state of a toolbar... but you could be a lot more creative and use some more complex conditions.
For example, you could create a condition that depends on some other javascript variable in your page, or perhaps a condition that depends on the actual time or date.
The possibilities are just endless...

Modifying the Visibility Condition programmatically

The state of a toolbar can also be changed by directly accessing the variable that controls their visibility by adding some code into an HTML document.
For example, this code will turn the toolbar number 1 off:

<script language="JavaScript">
    tbVisC[1] = new Function("return false");
    SetupToolbar();
</script>

The first line of code defines the body of a simple function that returns a false value setting the visibility state for the toolbar number 1 to be hidden.
The second line of code causes a refresh in all the toolbars by re-evaluating all their parameters. If the second line is omitted the visibility state will not change.

Creating a blinking effect

Although it may not be a useful thing to have a toolbar blink it demonstrates the power and versatility of this new feature in DHTML Menu Builder 4.1 (and above)
Here's the code used in the Visibility Condition of the toolbar:

var m=new Date().getMilliseconds(); if(!SM)window.setTimeout("SetupToolbar()", 100); return (m<800);

First of all, notice that the code must always be contained in a single line and must always return either true or false.
So, let's analyze the code, piece by piece:

var m=new Date().getMilliseconds();

The first piece of code queries the system and retrieves the current time, but only the milliseconds. The result is stored in the variable 'm'.
The second section of the code:

if(!SM)window.setTimeout("SetupToolbar()", 100);

This code setups a timer so the SetupToolbar() function is called again. This will force the code to keep re-evaluating our condition until the page is unloaded. Notice that this timer is only required on Internet Explorer; this is why we use the "if(!SM)" condition, which means: "...if its not a mozilla-based browser, then...".
And finally, the third piece of code:

return (m<800);

...is the return statement.
In this statement we're comparing the value in the variable 'm' with the number 800. If the value in 'm' is less than 800 the function will return true, otherwise it will return false.

This causes the function to return true for about 800 milliseconds and false for about 200. This will cause the toolbar to remain invisible (hidden) for about 200 milliseconds per every second.
 
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