NAME

HList - Create and manipulate Tix Hierarchial List widgets

SYNOPSIS

$hlist = $parent->HList(?options?);

STANDARD OPTIONS


background borderWidth cursor foreground font height highlightColor highlightThickness relief selectBackground selectForeground xScrollCommand yScrollCommand width

See the ``options'' manual entry for details on the standard options.

WIDGET-SPECIFIC OPTIONS


Name: browsecmd
Class: BrowseCmd
Switch: -browsecmd

Specifies a TCL command to be executed when the user browses through the entries in the HList widget.


Name: columns
Class: Columns
Switch: -columns

Specifies the number of columns in this HList widget. This option can only be set during the creation of the HList widget and cannot be changed subsequently.


Name: command
Class: Command
Switch: -command

Specifies the TCL command to be executed when the user invokes a list entry in the HList widget. Normally the user invokes a list entry by double-clicking it or pressing the Return key.


Name: drawBranch
Class: DrawBranch
Switch: -drawbranch

A Boolean value to specify whether branch line should be drawn to connect list entries to their parents.


Name: foreground
Class: Foreground
Switch: -foreground
Alias: -fg

[OBSOLETE] Specifies the default foreground color for the list entries.


Name: gap
Class: Gap
Switch: -gap

[OBSOLETE] The default distance between the bitmap/image and the text in list entries.


Name: height
Class: Height
Switch: -height

Specifies the desired height for the window in characters.


Name: indent
Class: Indent
Switch: -indent

Specifies the amount of horizontal indentation between a list entry and its children. Must be a valid screen distance value.


Name: itemType
Class: ItemType
Switch: -itemtype

Specifies the default type of display item for this HList widget. When you call the add and addchild methods, display items of this type will be created if the -itemtype option is not specified .


Name: padX
Class: Pad
Switch: -padx

[OBSOLETE] The default horizontal padding for list entries.


Name: padY
Class: Pad
Switch: -padx

[OBSOLETE] The default vertical padding for list entries.


Name: selectBackground
Class: SelectBackground
Switch: -selectbackground

Specifies the background color for the selected list entries.


Name: selectBorderWidth
Class: BorderWidth
Switch: -selectborderwidth

Specifies a non-negative value indicating the width of the 3-D border to draw around selected items. The value may have any of the forms acceptable to Tk_GetPixels.


Name: selectForeground
Class: SelectForeground
Switch: -selectforeground

Specifies the foreground color for the selected list entries.


Name: selectMode
Class: SelectMode
Switch: -selectmode

Specifies one of several styles for manipulating the selection. The value of the option may be arbitrary, but the default bindings expect it to be either single, browse, multiple, or extended; the default value is single.


Name: sizeCmd
Class: SizeCmd
Switch: -sizecmd

Specifies a TCL script to be called whenever the tixHList widget changes its size. This command can be useful to implement "user scroll bars when needed" features.


Name: separator
Class: Separator
Switch: -separator

Specifies the character to used as the separator character when intepreting the path-names of list entries. By default the character "." is used.


Name: width
Class: Width
Switch: -width

Specifies the desired width for the window in characters.


DESCRIPTION

The tixHList command creates a new window (given by the $widget argument) and makes it into a HList widget. Additional options, described above, may be specified on the command line or in the option database to configure aspects of the HList widget such as its cursor and relief.

The HList widget can be used to display any data that have a hierarchical structure, for example, file system directory trees. The list entries are indented and connected by branch lines according to their places in the hierachy.

Each list entry is identified by a entryPath. The entryPath is a sequence of entry names separated by the separator charactor (specified by the -separator option). An entry name can be any string that does not contain the separator charactor, or it can be the a string that contains only one separator charactor.

For example, when "." is used as the separator charactor, "one.two.three" is the entryPath for a list entry whose parent is "one.two", whose parent is "one", which is a toplevel entry (has no parents).

Another examples: ".two.three" is the entryPath for a list entry whose parent is ".two", whose parent is ".", which is a toplevel entry.

DISPLAY ITEMS

Each list entry in an HList widget is associated with a display item. The display item determines what visual information should be displayed for this list entry. Please see the DItem(n) manual page for a list of all display items. When a list entry is created by the add or addchild widget commands, the type of its display item is determined by the -itemtype option passed to these commands. If the -itemtype is omitted, then by default the display item type text is used.

WIDGET METHODS

The tixHList command creates a widget object whose name is the same as the path name of the HList widget's window. This command may be used to invoke various operations on the widget. It has the following general form:

$hlist->method(?arg arg ...?)


PathName is the name of the command, which is the same as the HList widget's path name. Option and the args determine the exact behavior of the command. The following commands are possible for HList widgets:
$hlist->add(entryPath, ?option, value, ...?)
Creates a new list entry with the pathname entryPath. A list entry must be created after its parent is created (unless this entry is a top-level entry, which has no parent). This command returns the entryPath of the newly created list entry. The following configuration options can be given to configure the list entry:
-at position
Insert the new list at the position given by position. position must be a valid integer. the Position 0 indicates the first position, 1 indicates the second position, and so on.
-after afterWhich
Insert the new list entry after the entry identified by afterWhich. afterWhich must be a valid list entry and it mush have the same parent as the new list entry
-before beforeWhich
Insert the new list entry before the entry identified by beforeWhich. beforeWhich must be a valid list entry and it mush have the same parent as the new list entry
-data string
Specifies a string to associate with this list entry. This string can be queried by the info method. The application programmer can use the -data option to associate the list entry with the data it represents.
-itemtype type
Specifies the type of display item to be display for the new list entry. type must be a valid display item type. Currently the available display item types are imagetext, text, and $widget. If this option is not specified, then by default the display item type specified by the -itemtype widget option is created.
-state
Specifies whether this entry can be selected or invoked by the user. Must be either normal or disabled. The add method accepts additional configuration options to configure the display item associated with this list entry. The set of additional configuration options depends on the type of the display item given by the -itemtype option. Please see the DItem(n) manual page for a list of the configuration options for each of the display item types.
$hlist->addchild(parentPath, ?option, value, ..., ?)
Adds a new child entry to the children list of the list entry identified by parentPath. Or, if parentPath is set to be the empty string, then creates a new toplevel entry. The name of the new list entry will be a unique name automatically generated by the HList widget. Usually if parentPath is foo, then the entryPath of the new entry will be foo.1, foo.2, ... etc. This command returns the entryPath of the newly created list entry. option can be any option for the add method.
$hlist->anchorSet(entryPath)
Sets the anchor to the list entry identified by entryPath. The anchor is the end of the selection that is fixed while dragging out a selection with the mouse.
$hlist->anchorClear
Remove the anchor, if any, from the this tixHList widget. This only removes the surrounding highlights of the anchor entry and does not affect its selection status.
$hlist->cget(option)
Returns the current value of the configuration option given by option. Option may have any of the values accepted by the tixHList command.
'
$hlist->column(col, ?)-char? ?width? Querys or sets the width of a the column col in the HList widget. The value of col is zero-based: 0 stands for the first column, 1 stands for the second, and so on. If no further parameters are given, returns the current width of this column (in number of pixels). Additional parameters can be given to set the width of this column:

$hlist->column(col){}
An empty string indicates that the width of the column should be just wide enough to display the widest element in this column. In this case, the width of this column may change as a result of the elements in this column changing their sizes.
$hlist->column(col, width)
width must be in a form accepted by Tk_GetPixels(3).
$hlist->column(col, -char, nChars)
The width is set to be the average width occupied by nChars number of characters of the font specified by the -font option of this HList widget.
'
$hlist->configure(?option?, ?value, option, value, ...?) Query or modify the configuration options of the widget. If no option is specified, returns a list describing all of the available options for $widget (see configure for information on the format of this list). If option is specified with no value, then the command returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given widget option(s) to have the given value(s); in this case the command returns an empty string. Option may have any of the values accepted by the tixHList command.
$hlist->delete(option, entryPath)
Delete one or more list entries. option may be one of the following:
all
Delete all entries in the tixHList. In this case the entryPath does not need to be specified.
entry
Delete the entry specified by entryPath. and all its offsprings, if any.
offsprings
Delete all the offsprings, if any, of the entry specified by entryPath. However, entryPath itself is not deleted.
siblings
Delete all the list entries that share the same parent with the entry specified by entryPath. However, entryPath itself is not deleted.
$hlist->dragsiteSet(entryPath)
Sets the dragsite to the list entry identified by entryPath. The dragsite is used to indicate the source of a grag-and-drop action. Currently drag-and-drop functionality has not been implemented in Tix yet.
$hlist->dragsiteClear
Remove the dragsite, if any, from the this tixHList widget. This only removes the surrounding highlights of the dragsite entry and does not affect its selection status.
$hlist->dropsiteSet(entryPath)
Sets the dropsite to the list entry identified by entryPath. The dropsite is used to indicate the target of a grag-and-drop action. Currently drag-and-drop functionality has not been implemented in Tix yet.
$hlist->dropsiteClear
Remove the dropsite, if any, from the this tixHList widget. This only removes the surrounding highlights of the dropsite entry and does not affect its selection status.
$hlist->entrycget(entryPath, option)
Returns the current value of the configuration option given by option for the entry indentfied by entryPath. Option may have any of the values accepted by the tixHList add command.
$hlist->entryconfigure(entryPath, ?option?, ?value, option, value, ...?)
Query or modify the configuration options of the list entry indentfied by entryPath. If no option is specified, returns a list describing all of the available options for entryPath (see Tk_ConfigureInfo for information on the format of this list). If option is specified with no value, then the command returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given option(s) to have the given value(s); in this case the command returns an empty string. Option may have any of the values accepted by the add or addchild method. The exact set of options depends on the value of the -itemtype option passed to the the add or addchild method when this list entry is created.
$hlist->hide(option, ?entryPath?)
Makes some of entries invisible invisible without deleting them. option can be one of the following:
entry
Hides the list entry identified by entryPath.

Currently only the entry option is supported. Other options will be added in the next release.

$hlist->info(option, arg, ...)
Query information about the tixHList widget. option can be one of the following:
$hlist->info(anchor, entryPath)
Returns the entryPath of the current anchor, if any, of the HList widget. If the anchor is not set, returns the empty string.
$hlist->info(children, ?entryPath?)
If entrpyPath is given, returns a list of the entryPath's of its children entries. Otherwise returns a list of the toplevel entryPath's.
$hlist->info(dragsite, entryPath)
Returns the entryPath of the current dragsite, if any, of the HList widget. If the dragsite is not set, returns the empty string.
$hlist->info(dropsite, entryPath)
Returns the entryPath of the current dropsite, if any, of the HList widget. If the dropsite is not set, returns the empty string.
$hlist->info(exists, entryPath)
Returns a boolean value indicating whether the list entry entrpyPath exists.
$hlist->info(hidden, entryPath)
Returns a boolean value indicating whether the list entry entrpyPath is hidden or not.
$hlist->info(next, entryPath)
Returns the entryPath of the list entry, if any, immediately below this list entry. If this entry is already at the bottom of the HList widget, returns an empty string.
$hlist->info(parent, entryPath)
Returns the name of the parent of the list entry indified by entrpyPath. If entrpyPath is a toplevel list entry, returns the empty string.
$hlist->info(prev, entryPath)
Returns the entryPath of the list entry, if any, immediately above this list entry. If this entry is already at the top of the HList widget, returns an empty string.
$hlist->info(selection)
Returns a list of selected elements in the HList widget. If no entries are selectd, returns an empty string.
$hlist->item(option, ?args, ...?)
Creates and configures the display items at individual columns the entries. The form of additional of arguments depends on the choice of option:
$hlist->item(cget, entryPath, col, option)
Returns the current value of the configure option of the display item at the column designated by col of the entry specified by entryPath.
$hlist->item(configure, entryPath, col, ?option?, ?value, option, value, ...?)
Query or modify the configuration options of the display item at the column designated by col of the entry specified by entryPath. If no option is specified, returns a list describing all of the available options for entryPath (see Tk_ConfigureInfo(3) for information on the format of this list). If option is specified with no value, then the command returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given option(s) to have the given value(s); in this case the command returns an empty string. Option may have any of the values accepted by the item create method. The exact set of options depends on the value of the -itemtype option passed to the the item create method when this display item entry was created.
$hlist->item(create, entryPath, col, ?)-itemtype type? ?option value ...?
Creates a new display item at the column designated by col of the entry specified by entryPath. An optional parameter -itemtype can be used to specify what type of display items should be created. By default a imagetext display item is created. Additional parameters, in option-value pairs, can be passed to configure the appearance of the display item. Each option- value pair must be a valid option for this type of display item.
$hlist->item(delete, entryPath, col)
Deletes the display item at the column designated by col of the entry specified by entryPath.
$hlist->nearest(y)
Given a y-coordinate within the tixHList window, this command returns the entryPath of the (visible) tixHList element nearest to that y-coordinate.
$hlist->see(entryPath)
Adjust the view in the tixHList so that the element given by index is visible. If the element is already visible then the command has no effect; if the element is near one edge of the window then the tixHList scrolls to bring the element into view at the edge; otherwise the tixHList scrolls to center the element.
$hlist->selection(option, arg, ...)
This command is used to adjust the selection within a tixHList widget. It has several forms, depending on option:
$hlist->selectionClear(?from?, ?to?)
When no extra arguments are given, deselects all of the list entrie(s) in this tixHList widget. When only from is given, only the list entry identified by from is deselected. When both from and to are given, deselects all of the list entrie(s) between between from and to, inclusive, without affecting the selection state of elements outside that range.
$hlist->selectionIncludes(entryPath)
Returns 1 if the list entry indicated by entryPath is currently selected, 0 if it isn't.
$hlist->selectionSet(from, ?to?)
Selects all of the list entrie(s) between between from and to, inclusive, without affecting the selection state of elements outside that range. When only from is given, only the list entry identified by from is selected.
$hlist->show(option, ?entryPath?)
Show the entries that are hidden by the hide command, option can be one of the following:
entry
Shows the list entry identified by entryPath.

Currently only the entry option is supported. Other options will be added in the next release.

$hlist->xview(args)
This command is used to query and change the horizontal position of the information in the widget's window. It can take any of the following forms:
$hlist->xview
Returns a list containing two elements. Each element is a real fraction between 0 and 1; together they describe the horizontal span that is visible in the window. For example, if the first element is .2 and the second element is .6, 20% of the HList text is off-screen to the left, the middle 40% is visible in the window, and 40% of the text is off-screen to the right. These are the same values passed to scrollbars via the -xscrollcommand option.
$hlist->xview(entryPath)
Adjusts the view in the window so that the list entry identified by entryPath is aligned to the left edge of the window.
$hlist->xview(moveto => fraction)
Adjusts the view in the window so that fraction of the total width of the HList is off-screen to the left. fraction must be a fraction between 0 and 1.
$hlist->xview(scroll => number, what)
This command shifts the view in the window left or right according to number and what. Number must be an integer. What must be either units or pages or an abbreviation of one of these. If what is units, the view adjusts left or right by number character units (the width of the 0 character) on the display; if it is pages then the view adjusts by number screenfuls. If number is negative then characters farther to the left become visible; if it is positive then characters farther to the right become visible.
$hlist->yview(?args?)
This command is used to query and change the vertical position of the text in the widget's window. It can take any of the following forms:
$hlist->yview
Returns a list containing two elements, both of which are real fractions between 0 and 1. The first element gives the position of the list element at the top of the window, relative to the HList as a whole (0.5 means it is halfway through the HList, for example). The second element gives the position of the list entry just after the last one in the window, relative to the HList as a whole. These are the same values passed to scrollbars via the -yscrollcommand option.
$hlist->yview(entryPath)
Adjusts the view in the window so that the list entry given by entryPath is displayed at the top of the window.
$hlist->yview(moveto => fraction)
Adjusts the view in the window so that the list entry given by fraction appears at the top of the window. Fraction is a fraction between 0 and 1; 0 indicates the first element in the HList, 0.33 indicates the element one-third the way through the HList, and so on.
$hlist->yview(scroll => number, what)
This command adjust the view in the window up or down according to number and what. Number must be an integer. What must be either units or pages. If what is units, the view adjusts up or down by number lines; if it is pages then the view adjusts by number screenfuls. If number is negative then earlier elements become visible; if it is positive then later elements become visible.

BINDINGS

  1. If the -selectmode is "browse", when the user drags the mouse pointer over the list entries, the entry under the pointer will be highlighted and the -browsecmd procedure will be called with one parameter, the entryPath of the highlighted entry. Only one entry can be highlighted at a time. The -command procedure will be called when the user double-clicks on a list entry.
  2. If the -selectmode is "single", the entries will only be highlighted by mouse <ButtonRelease-1> events. When a new list entry is highlighted, the -browsecmd procedure will be called with one parameter indicating the highlighted list entry. The -command procedure will be called when the user double-clicks on a list entry.
  3. If the -selectmode is "multiple", when the user drags the mouse pointer over the list entries, all the entries under the pointer will be highlighted. However, only a contiguous region of list entries can be selected. When the highlighted area is changed, the -browsecmd procedure will be called with an undefined parameter. It is the responsibility of the -browsecmd procedure to find out the exact highlighted selection in the HList.
  4. If the -selectmode is "extended", when the user drags the mouse pointer over the list entries, all the entries under the pointer will be highlighted. The user can also make disjointed selections using <Control-ButtonPress-1>. When the highlighted area is changed, the -browsecmd procedure will be called with an undefined parameter. It is the responsibility of the -browsecmd procedure to find out the exact highlighted selection in the HList.
  5. Arrow key bindings: <Up> arrow key moves the anchor point to the item right on top of the current anchor item. <Down> arrow key moves the anchor point to the item right below the current anchor item. <Left> arrow key moves the anchor to the parent item of the current anchor item. <Right> moves the anchor to the first child of the current anchor item. If the current anchor item does not have any children, moves the anchor to the item right below the current anchor item.

EXAMPLE

This example demonstrates how to use an HList to store a file directory structure and respond to the user's browse events:


tixHList .h -separator "/" -browsecmd browse -selectmode single .h add / -text / .h add /home -text /home .h add /home/ioi -text /home/ioi .h add /home/foo -text /home/foo .h add /usr -text /usr .h add /usr/lib -text /usr/lib pack .h proc browse {file} { puts "$file browsed" }

BUGS

The fact that the display item at column 0 is implicitly associated with the whole entry is probably a design bug. This was done for backward compatibility purposes. The result is that there is a large overlap between the item command and the add, addchild, entrycget and entryconfigure commands. Whenever multiple columns exist, the programmer should use ONLY the item command to create and configure the display items in each column; the add, addchild, entrycget and entryconfigure should be used ONLY to create and configure entries.

KEYWORDS

Tix(n), hierarchical listbox