In the previous parts we have learned how to create, manipulate, and transform a graphic object. There are also other ways how to alter the object's appearance. Select the object (see Selection to find out how) and open the Property window by choosing either the “Edit/Properties” or the “Windows/Property window” menu item. The two ways differ slightly, as described in The Property Window. Basically, the Property window opened in the latter way reacts to selection changes and updates the displayed objects accordingly. Also, you can edit properties of multiple objects in it.
The property window contains the list of all properties of the selected object(s). You can change their values here; however, the attempt to change some of them may fail for various reasons, mainly the geometric dependencies. If you try to change the coordinates of the center point of a circle determined by three points on its perimeter, it fails. In that case, the value remains unchanged.
Some values can be edited directly by putting down the new value or using the arrows in spin buttons (edit boxes with arrows that changing the value by certain predefined steps). Some values are to be chosen from the list and for some property types, an editor will be opened (text, color, ...).
The “invisible” property allows you to make any object invisible on the drawing area. But physically, it is still in the object tree (see Universe Browser) and can play part in geometric dependencies.
You can also create, edit, and delete your own properties; that can be useful for making some notes or in script processing. To add a property, press the “Add ...” button and fill in the name (the key), type, subtype and value of this property. Note that the property key must be unique. To delete some properties, select them by clicking their names in the Property window (or unselect by clicking once more). Then press the “Delete” button. Note that not all properties can be deleted; some of them are important for geometric and graphic features of the object. But you can always delete the properties you created yourself. Even these property actions can be undone and redone using the local undo/redo.