Accessing Views Between Layout Windows

One of the Newton 2.x OS Q&As
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This document was exported on 7/23/97.

Accessing Views Between Layout Windows (6/7/94)

Q: I have problems setting a protoStaticText text slot that is in one linked layout window from a button that is in another linked layout window. I tried to allow access to the base view from both linked layouts, but this didn't help. I even tried to allow access from the base view to both layouts, but this didn't help, either. What should I do?

A: There is no way to declare views across the artifical boundary imposed by the linked layouts. Until this feature of NTK is implemented, you must either create the link yourself at run time, or declare the button to the top level of the linked layout, and then declare the link.

For example, consider a view called textThatChanges which a child of a view called changingContainer and is declared to changingContainer with the name textThatChanges. ChangingContainer is the base view for a layout which is linked into the main layout, and the link (in the main layout) is declared as changingContainerLink. Code in the main layout can change the text of the textThatChange view like so:
    SetValue(containerLink.whatToDo, 'text, "Turn and face the...")


To do the equivalent of the declare yourself:

1) In the viewSetupFormScript script of the 'buttonThatChanges button, set the value of the base view's slot 'theTextView to self, as in the following code fragment:
    func()
    begin
           base.theTextView := self;
    end

2) In the buttonClickScript script of the 'buttonThatSetsText button, use the global function SetValue to store new text in the text slot of the 'buttonThatChanges button, as in the following code fragment:

    func()
    begin
       SetValue(base.theTextView, 'text, "Now something happened!");
    end

Note that this example assumes the self-declared view called base. In your application, you may access your base view in a different way.