You can create navigation bar buttons that stretch as you change the amount of text on them.

Is static

Changing the text does not change the size of the button.

Extends

Increasing the text stretches the button from its center.

Decreasing the text shrinks the button if possible. Shrinking stops when the button is about to become distorted.

Note: if in Bar Properties you have Equal size selected, the button size is controlled by the largest text message.

Scales

Changing the text scales the button - the same effect as stretching the object using the Selector Tool).

Note: if in Bar Properties you have Equal size selected, the button size is controlled by the largest text message.

An example of the difference between Extend and Scales is a rectangle with rounded ends. Extend stretches the center of the rectangle; the corner radius is unchanged. Scales elongates the entire rectangle and the round corners become elliptical. After creating the button, you can use the Name gallery for greater control over stretching and extending.

If you want some objects in the button non-stretching, group them and then select Groups do not stretch in the dialog box.