ContentsWhat is fGUI ?
fGUI basics The classesfApplicationfClassInfo fColor fGroup fObject fPoint |
fGUI basics
LayoutThe basic element of a fGUI user interface is the fObject class. All visual elements of the system are derived from that class. The elements are arranged using classes derived from fGroup, an instance of which is for example the fVerticalGroup class which arranges objects in a row. To arrange the objects these key elements are used:
In addition to the five basic attributes two more are needed for a correct layout:
Enhanced LayoutA tiny bit of information is missing in the above description: Every object has a small border around it (by default 1.0 pixels) that belongs to the object but in which the object should not draw ! This border is necessary for cosmetic purposes only, otherwise the objects would be too close together.You only need to remember that when you write your own classes derived from fObject, which normally isn't not necessary. DrawingThe root of drawing is the fView class, it passes the Draw() calls it receives to the corresponding draw() method.Contrary to the Be philosophy not every object has its own drawing environment, each object is responsible for setting the parameters of the target BView according to its own needs.Another possibility to draw is when an object has to react to an user input outside the regular call to draw(). This is used very often, for example in the fTextInput and the scrollbar classes.
The flexible GUI, in HTML for the BeOS Release 3. Copyright © 1997-1998 Stegemann & Co. All rights reserved. Last modified May 19, 1998. |