How to Get Data From a ProtoTXView Externalized Data

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

How to Get Data From a ProtoTXView Externalized Data (4/3/97)

Q: I'm using the protoTXView text engine in Newton 2.1 OS. How can I get text, styles, pictures, etc. out of the object returned by protoTXView's Externalize method without either a) instantiating a protoTXView or b) digging in the data structure?

A: You must instantiate a view to get data from the externalized object that protoTXView produces. The data structures in that object are not documented or supported. You may be tempted to do this anyway, since it looks as though the data structure is obvious. Don't, it isn't. ProtoTXView actually uses several different data formats depending on the complexity and storage destination for the data.

It's actually very easy to instantiate a view based on protoTXView to get at the data. Here's one way:
    local textView := BuildContext(
        {
            _proto: protoTXView,
            viewBounds: SetBounds(0, 0, 0, 0),
            viewFlags: 0,
            ReorientToScreen: ROM_DefRotateFunc,
        });
    textView:Open();
    textView:Internalize(myExternalizedData);

You can now use all the protoTXView APIs to get the data from the textView object. Don't forget to clean up with textView:Close() when you're done.