The Lively Kernel has a class browser that allows
the behavior of the system to be viewed and edited interactively.
The upper left panel of the browser contains the names of the
Lively Kernel (JavaScript) classes in the system.
When you select one of them, the upper right panel shows
all the methods (functions) of that class.
When you choose one of the methods, the lower panel shows the
source code of the method.
Notes:
To save changes after editing a method, use the "accept changes"
operation that is available in the popup menu of the method panel.
You can also use the keyboard shortcuts defined below.
There are various keyboard shortcuts available to edit the methods.
(NOTE: these shortcuts do not work on all browsers. In some browsers
you may have to use the "Alt Gr" key instead):
Alt-S ("Save-It"): Save (accept) the changes
Alt-A: Select All
Alt-X: Cut
Alt-C: Copy
Alt-V: Paste
Alt-Z: Undo
Some additional comments on text editing:
Typing replaces selection.
Double-clicking selects a word; triple-clicking selects the entire text.
Double-clicking near a bracket, parenthesis or a JavaScript comment (/* ... */)
selects text inside the brackets/parentheses/comment.
Try it yourself! Try viewing the methods of class RectShape.
Try editing some of the methods to make changes to the behavior of the system
itself.
For instance, if you modify the method RectShape.setFill as shown below,
you change the way menus and many other objects in the system are drawn.
You have to accept the changes by pressing Alt-S or by choosing
the "evaluate as JavaScript code"
popup menu item of the text that you just edited.