Documentation

Features of the Migration Tool

The migration tool helps you convert your apps by reading in a GUIDE FIG file and automatically generating the App Designer equivalent components and layout in an MLAPP file. Your GUIDE callback code and other user-defined functions are copied into the MLAPP file. This semi-automated code conversion also creates a migration report that suggests actions for any manual code updates that are needed. Some features of the tool are described in this table.

Callback Code

In order to make your GUIDE-style callback code compatible with the App Designer UI components in your app, the migration tool uses a function called convertToGUIDECallbackArguments. This function converts App Designer callback arguments into the GUIDE-style callback arguments that your code requires. The convertToGUIDECallbackArguments function is added to the beginning of each migrated callback function. It takes the App Designer callback arguments app and event and returns the GUIDE-style callback arguments hObject, eventdata, and handles. For example:

hObject is the handle of the object whose callback is executing. For components from your GUIDE app that were UIControl or ButtonGroup objects, hObject is a handle to a UIControlPropertiesConverter or ButtonGroupPropertiesConverter object. These objects are created to make your GUIDE-style code work in your App Designer callback functions.

eventdata is usually empty, but can be a structure containing specific information about the callback event.

handles is a structure that contains the migrated child components of the UI figure that have a 'Tag' property value set. Child components that were UIControl objects in your GUIDE app are UIControlPropertiesConverter objects in the migrated app. Similarly, child ButtonGroup objects are ButtonGroupPropertiesConverter objects in the migrated app.

The UIControlPropertiesConverter and ButtonGroupPropertiesConverter objects act like adapters between the GUIDE-style code and the App Designer components and callbacks. A UIControlPropertiesConverter object is created for each component in your GUIDE app that was a UIControl object. These converter objects are associated with an App Designer UI component in your migrated app. The converter object has the same properties and values as the original UIControl from your GUIDE app, but it applies them to its associated App Designer UI component.

Similarly, for ButtonGroup objects from GUIDE, a ButtonGroupPropertiesConverter object is created in App Designer. This object makes it possible to set the SelectedObject property to a UIControlPropertiesConverter object so that button group SelectionChangedFcn callback logic will function.

Special Considerations

There are some circumstances that require you to take extra steps before or after you migrate your app. This table lists common scenarios and coding patterns that require extra steps or manual code updates. This is not intended to be a comprehensive list.

function out = MyGUIDEApp(varargin)
    app = MyMigratedApp(varargin{:});
    out = app.UIFigure;            
end

If your GUIDE app integrates third-party components using functions like actxcontrol, see Recommendations for MATLAB Apps Using Java and ActiveX.

Aids for Adding New Features or Fully Adopting App Designer Code Style

App Designer and GUIDE have different code structures, callback syntaxes, and techniques for accessing UI components and sharing data. Understanding these differences is useful if you plan to add new App Designer features to your migrated app or want to update it to use App Designer code style and conventions. This table summarizes some of these differences.