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Article #25644: What are Delphi and C++ Builder Action Lists and how do I use them?

Problem:
What are Delphi and C++ Builder Action Lists and how do I use them?
Solution:
What are Action Lists?
Action lists are a way of linking controls that perform similar tasks.
Why use Action Lists?
This is a time saver. Once controls are linked, changes made to
an action list item will propagate to all components tied to that action item.
Action List Demo Objective:
To make the File | New command use an action list item
Start New application
Add MainMenu component to the form
Double click MainMenu component  — To import File Menu template
Right click Form1.MainMenu
Select Insert from Template
Select File Menu
Click OK
Add ActionList component to the form
Double click ActionList component  This will display the Action List editor
Click New Action  — This action will be responsible for the New File
Click Object Inspector
Click Name Change to: actNewFile
Click Caption Change to: &New
Click Shortcut Change to: CTRL+N
Double click MainMenu component
Click Object Inspector
Click Action Change to: actNewFile  You can also use the down arrow to select this
Go to Action List Editor
Double click actNewFile
Click Object Inspector
Click Events tab  This will display 3 properities: OnExecute, OnHint, & OnUpdate
Double click OnExecute
Enter ShowMessage(Create New File);
Save All
If we ran the application now, selecting File | New would trigger the message Create New File
The benefit of saving time occurs when you have multiple components.
Add Button component to the form
Click Properties tab of the Object Inspector
Click Action Change to: actNewFile — You can also use the down arrow to select this
Add CheckBox component to the form
Click Object Inspector
Click Action Change to: actNewFile
Doing the above will now tie the Button and CheckBox component properties to that action
Run the application
Change one line of code, save all, and then run the application again.
That change will propagate to all components in the action list we created.

Last Modified: 24-OCT-00