How do I iterate every TActionClientItem in a TActionManager.ActionBars class? - delphi

Question

Problem
I like to use the TActionManager component as a better way of managing events and building the menu interfaces either using TMainMenu or TActionMainMenuBar, for this though we would be using the TActionMainMenuBar because of the ActionBars property in the TActionManager.
One annoying issue I have is with the image indexes sometimes getting lost and more often then not it means having to go through each ActionBar item and manually entering the image index again, a pain if you are adding/deleting actions and images etc.
To solve this I came up with the idea of iterating through each TActionClientItem and assigning the image index which is determined by its assigned TAction.
Here is what I came up with so far:
procedure TMyComponent.ReassignActionImages;
var
I, J, K: Integer;
Manager: TActionManager;
BarItem: TActionBarItem;
Client: TActionClientItem;
Action: TAction;
begin
for I := 0 to Owner.ComponentCount -1 do
begin
if (Owner.Components[I].ClassType = TActionManager) then
begin
Manager := TActionManager(Owner.Components[I]);
for J := 0 to Manager.ActionBars.Count -1 do
begin
BarItem := Manager.ActionBars.ActionBars[J];
if BarItem.ActionBar <> nil then
begin
for K := 0 to BarItem.Items.Count -1 do
begin
Client := BarItem.Items[K];
if Client.Action <> nil then
begin
Action := TAction(Client.Action);
if Action <> nil then
begin
Client.ImageIndex := Action.ImageIndex;
//ShowMessage('Has Action: ' + Manager.Name + ' - ' + Action.Name + ' - ' + Client.Caption);
end;
end;
end;
end;
end;
end;
end;
end;
While this does seem to work, it does not appear to process child items. I think I need some kind of recursive procedure but I am not sure how to implement that. From what I understand from recursion it basically means running the same procedure within a procedure?
Steps to reproduce lost TActionClientItem image indexes using one scenario:
Create a New Project.
Add TActionManager to Form.
Add TAction to the TActionManager, leave ImageIndex as -1.
Add TActionMainMenuBar to Form.
Select the TActionManager in the Form Designer then edit the ActionBars property.
Add a new TActionBarItem.
In the Object Inspector assign the TActionMainMenuBar as the ActionBar.
Still in the Object Inspector click the Items (TActionClients) property.
Add a new TActionClientItem, give it a caption such as &File.
Click Items (TActionClients) property again.
Add a new TActionClientItem.
In the Object Inspector assign the TAction (eg, Action1) to the Action property.
Drop a TImageList on the Form, and add a bitmap.
Select the TActionManager in the Form Designer again and assign the TImageList to the Images property.
Double Click the TActionManager and for Action1 change the ImageIndex to 0
Run the application, notice there is no image showing.
The &File menu item will also be disabled so just edit the .OnExecute event for the TAction if you wish.
Run again, still no image showing.
Solution for the above scenario:
To make the image visible, edit the ActionBars and find the TActionClientItem manually setting the Image index to 0.
Run the application and the image will show.
So the above is one scenario I can reproduce that shows how the imageindex of a TAction is not updated to reflect the changes in a TActionClientItem.
There are other times that this has happened (usually when adding, deleting or editing TActions and images) where a manual update of the TActionClientItem is required.
This is why I decided to try and make a simple component which would ensure the images are syncronized at all times, and that no matter if the TActionClientItem imageindex is lost or becomes redundant, if it has a TAction assigned that has a imageindex I want that imageindex linked back with the TActionClientItem.

Answer 1

I am actually a bit pleased because for once I am able to solve a not so obvious simple problem!
The solution is to call IterateClients on the TActionManager.ActionBars and by using a callback procedure we can then access each TActionClientItem.
Useful documentation links:
http://docwiki.embarcadero.com/VCL/XE/en/ActnMan.TActionBars
http://docwiki.embarcadero.com/VCL/XE/en/ActnMan.TActionBars_Inherited_Members
http://docwiki.embarcadero.com/VCL/XE/en/ActnMan.TActionClientsCollection.IterateClients
In code this what I managed to do:
TMyComponent = class(TComponent)
protected
procedure Loaded; override;
procedure ActionCallBack(Client: TActionClient);
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
end;
and
procedure TMyComponent.Loaded;
procedure SyncImages;
var
I: Integer;
Manager: TActionManager;
begin
for I := 0 to Owner.ComponentCount -1 do
begin
if (Owner.Components[I].ClassType = TActionManager) then
begin
Manager := TActionManager(Owner.Components[I]);
Manager.ActionBars.IterateClients(Manager.ActionBars, ActionCallBack);
end;
end;
end;
begin
inherited Loaded;
SyncImages;
end;
{ ---------------------------------------------------------------------------- }
procedure TMyComponent.ActionCallBack(Client: TActionClient);
begin
if (Client is TActionClientItem) then
begin
with TActionClientItem(Client) do
begin
if Action <> nil then
begin
Caption := TAction(Action).Caption; // if you want to sync caption
ImageIndex := TAction(Action).ImageIndex;
end;
end;
end;
end;