The FileTree List Widget

View Class: SelectionInTreeView
Spec Class: SelectionInTreeViewSpec

The FileTree List Widget is used to display a hierarchical list of files (a file directory).

The Basics Section:

ID	Unique symbolic name (ID) of the label. This ID can be used by the application to access the widget via "`builder>>componentAt:#`ID".
Model	Aspect selector or binding for the widgets model. Typically, the name of a method implemented in the application, which returns the model. The returned object should be a `ValueModel`* instance, holding the selection.
Root	Aspect selector or binding for the directory root of the tree. Typically, the name of a method implemented in the application, which returns a valueHolder holding the roots directory name or the directory name itself.

Popup Menu Selector	Aspect selector or binding for the building of a popup menu for the list widget. It should return a menu spec or a menu.
Popup Menu Performer	Aspect selector or binding for sending the messages of the popup menu items to an object. It should return an object which is able to receive the messages as specified in the menu items. If blank, the application gets the menu messages.
Menu Editor	Opens a Menu Editor on the popup menu spec.

Vertical Scroll Bar	Turns on/off that the list widget provides vertical scrolling capabilities.
Vertical Mini Scroll Bar	Turns on/off that the list widget uses a small vertical scroll bar. This attributes can only be set, if the attribute Vertical Scroll Bar is turned on.
Horizontal Scroll Bar	Turns on/off that the list widget provides horizontal scrolling capabilities.
Horizontal Mini Scroll Bar	Turns on/off that the list widget uses a small horizontal scroll bar. This attributes can only be set, if the attribute Horizontal Scroll Bar is turned on.
Auto Hide	Controls autoHiding of scrollbars. If on, scrollbars hide themself, if the contents is smaller than the scrolled view. If off, scrollBars never hide themSelf. If set to default, the autoHide feature is controlled by the viewStyle and scrollbars behave "natural" for the operating system. (true for windows, false for most unix-styles).

The Details1 Section:

Font	Defines the font style of the label. After selecting the check toggle the font style can be chosen by selecting one of the Family/Face/Style/Size buttons. If no font style is selected, the widget takes its default font style from the style sheet.
FG-Color	Defines the foreground color of the label. After selecting the check toggle the foreground color can be chosen by selecting the desired colored button. If no color is selected, the widget takes its default foreground color from the style sheet.
BG-Color	Defines the background color of the label. After selecting the check toggle the background color can be chosen by selecting the desired colored button. If no color is selected, the widget takes its default background color from the style sheet.
Border	Defines the width of the border.
Level	Defines the width of the 3D-border. Positive values provide a raising, negative values provide a lowering of the widget.

Lines	Controls if connecting lines are displayed.
Root	Controls if the trees root should be shown.
Indicators	Controls, if [+] / [-] indicators should be shown, indicating if a tree item has subitems (subItemIndicators).
Root Indicator	Controls, if a [+] / [-] subItem indicator should be shown for the root item.

Filter (Class)

The name of a file-filter class.
This is used to filter the directories files.
Only files passing the filter will be shown in the widget.
Two standard filters are provided:
- Directory, which filters all non directories
- File, which filters all directories.

The Details2 Section:

Allow multiple selections	If off, only a single item may be selected, If off, multiple items may be selected (shift-click), and the selection will consist of a collection.
Highlight	Controls how a selected item should be displayed. With line highlight style, the complete line is highlighted. With label, only the items label is highlighted.

Initially Disabled	Turns on/off that the widget is initially disabled.
Initially Invisible	Turns on/off that the widget is initially invisible.
Can Tab	Turns on/off that the widget can be reached by tabbing.
Monitoring	Enables automatic update of the view, whenever the directories contents changes. To do this, the widget will scan the file directory in regular intervals, for changes. If monitoring is enabled, the scan-interval is specified in seconds in the "Delay Time" field.

The Channels Section:

Enable

Aspect selector or binding for en-/disabling the widget.
It should return a

- Boolean instance** (only for static behavior)
- ValueModel* instance with a Boolean instance**

A value model is used to provide a dynamically changing of the ability of the widget.

Selected	Method invoked when the selection changes. This defines the name of a method in the application, which will be invoked whenever the row-selection changes. Using a callback may be more convenient than adding a change interest on the model (i.e. defining a notification with #onChange:send:to:).
Dbl-Click	Method invoked on double click. This defines the name of a method in the application, which will be invoked whenever the user double clicks on an item.
SelectCond	Method invoked to ask if selection is allowed. This defines the name of a method in the application, which will be invoked before a selection is made. If that method returns false, the item is not selected. The selector may be for a 0-arg or a 1-arg method; if its a 1-arg methodName, the node which is about to be selected will be passed as argument. This gives the application complete control over the selection. If left empty, selections are always allowed.
Dbl-Click	Method invoked on double click. This defines the name of a method in the application, which will be invoked whenever the user double clicks on an item.
Validate Dbl-Click	Method invoked before a subtree is opened via double click. This defines the name of a method in the application, which will be invoked whenever the user double clicks on an item, which contains subItems (i.e. is a subtree).

* = ValueHolder, AspectAdaptor, BufferedValueHolder, RangeAdaptor, TriggerValue
** = true, false

The Drag & Drop Section:

see document "Implementing Drag and Drop"

The Help Section:

see document "Using the Help Tool"

The Layout Section:

see document "The Layout of the Widgets"