Progress
AppBuilder
Developer’s Guide


Layout Inheritance Behavior at Run Time

At run time, inheritance always occurs from the master layout to all other layouts in the procedure file. However, inheritance is conditional in that a character layout does not inherit all of the widgets or properties in a graphical layout, and inheritance can be explicitly overridden.

Character Layout Inheritance

If Character Progress does not support a particular widget, a character layout cannot inherit the widget even if it appears in the master layout. Similarly, if Character Progress does not support a particular property for a widget, the character layout cannot inherit the property. For example, the height of Fill-ins, Combo Boxes, Toggle Boxes, Pushbuttons, and Text widgets is always 1 in a character interface.

When you create a character alternate layout, the AppBuilder changes the appearance of the design window and the widgets within the design window to fit within the limitations of a character environment. Thus, buttons can only be one line high, and the character window has a default width of 80 character units and a height of 21 character units. For more information, see the "Simulating Character Applications" section.

Overriding Layout Inheritance

If you change a property of a widget in an alternate layout, that layout no longer inherits the property from the master layout unless you explicitly re-establish layout inheritance. Also, if you insert a widget into an alternate layout, or delete a widget from an alternate layout, you disinherit the widget from the master layout.

There are two special cases:


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