One stretch action with two linear parameters

[david_m_brubacher]

I'm new to dynamic blocks so please pardon a potentially basic question.

Imagine a dimension with arrows at each end (this is just a simplified example. A real dimension won't do what I need).

It looks like this: <------------                         --------------->

I want to have a linear parameter affecting each leader on the arrows which restricts them to specific distances - I've used a list value set and works perfectly on a single arrow.

Now I want to drag the stretch grip on one arrow (lets say the left) and drag it longer or shorter, thus increasing or decreasing the X ordinate of its endpoint and I want the left arrow to stretch longer and shorter at the same time, but its X ordinate should decrease or increase. In other words, I want the gap between the ends of the leaders to increase or decrease and the leader lines to be the same length.

How do you accomplish this?

[Libbya]

It makes it easier to help if you post a file.  

Attached is a file with two ways to accomplish what I think you are asking.  Arrow1 has one grip.  The parameter extends from midpoint of the block to the right.  There are two actions associated with that parameter.  Both actions are associated with the single grip point.  One action moves the right arrow point with the grip.  The other action moves the left arrow point and has a distance multiplier of -1.  Arrow2 has two grips.  The parameter extends from one arrow point to the other.  The base location has been changed to midpoint.  There are two actions, one associated with each grip.