org.gnu.gtk
Class TreeView

java.lang.Object
  |
  +--org.gnu.glib.GObject
        |
        +--org.gnu.gtk.GtkObject
              |
              +--org.gnu.gtk.Widget
                    |
                    +--org.gnu.gtk.Container
                          |
                          +--org.gnu.gtk.TreeView

public class TreeView
extends Container

The TreeView object is a widget for displaying trees and lists. The sole purpose of this widget is for displaying the data on the screen and setting other parts of the view using the associated objects.

Gtk Tree and List Widgets Overview

The standard tree and list widgets in Gtk are very powerful, but somewhat complex. For your conveniance, the Java-Gnome project has derived a number of simpler classes for common uses of these widgets.

SimpleList
A single column list of string values.
todo...
todo...

If you choose not to use those, or your requirements are such that you cannot use them, you will have to learn how to use the full objects.

TreeView

There is only one widget which is placed in any applications to create trees, lists and tables. This is the TreeView. An application can have any number of treeviews and they can be placed as can normal widgets. The data for the widget, and the method in which it is displayed is controlled by other classes. Gtk has been designed so that any number of treeview widgets can be linked to the same data store. TreeViewColumns, CellRenderers and TreeSelections are created for each view, so Views can use the same data store but have their own column layout, data display within those columns (linked to any of the dataBlocks in the store); and their own selections.

TreeModel

Models are used to store data. Data is stored in what could be considered a table. There are a number of DataBlocks, which could be considered as data columns (in fact, in the C version of gtk, they are always refered to as columns; but this can get confused with TreeViewColumns which are quite a different matter). These dataBlocks each store one type of data (String, boolean, int, etc.). The 'rows' of the data table, or the individual records in the data store are accessible using iterators called TreeIters. These are used extensively in many methods. Setting data involves getting an iterator (usually be creating a new row) and then setting the value for each of the dataBlocks. The ordering of these dataBlocks has absolutely no meaning - you can decide exactly which blocks are used on screen by setting Attribute mappings to the CellRenderers which render data on the screen (see below).

Currently, there are two implementations of TreeModel

ListStore - This is used for tables and lists. Data is organised in rows and columns.

TreeStore - This is for the hierarchical trees. Data is organised using TreePath's.

TreeViewColumn

Both trees and lists can have multiple columns of data. Columns are added and removed using the TreeView class. Columns are objects which determine how the data is displayed. They have settings such as the column title, whether the column can be resized, and even whether the columns can be reorganized (by dragging the columns). Each TreeView widget has it's own set of columns. Determining how the data is displayed in the columns is done by CellRenderers (see below). Any number of renderers can be added to the same column

CellRenderer

Tree and list `cells' may contain a large variety of data types. Determining how they are displayed is done by the CellRenderer family of classes. If the data is unusual, or you want to combine a number of data types in a single column, you may construct your own renderer. However, you are recommended to stick with the regular choices:

CellRendererPixbuf
CellRendererText
For displaying Strings
CellRendererToggle
For displaying boolean data, either as individual checkboxes or as radio buttons.

The CellRenderer's need data to be able to display. This is set using the TreeViewColumn#addAttributeMapping(CellRenderer, CellRendererAttribute, int). The renderer attributes vary with each renderer, for example CellRendererText has a TEXT attribute for the text the be displayed. The final parameter is for the dataBlock in the store in which the data is contained.

Java-Gnome comes with a number of simple example applications involving trees. They may be useful for learning the functionality of these classes.

Author:
Mark Howard <mh@debian.org>

Constructor Summary
TreeView(int handle)
          Creates a new tree view from a native handle
TreeView(TreeModel model)
          Creates a new TreeView Widget with the initial model set
 
Method Summary
 void activateCell(TreePath path, TreeViewColumn column)
          Activates the cell determined by path and column.
 int appendColumn(TreeViewColumn column)
          Appends column to the list of columns.
 void collapseAll()
          Recursively collapses all visible, expanded nodes.
 boolean collapseRow(TreePath path)
          Collapses a row (hides its child rows, if they exist).
 void expandAll()
          Recursively expands all nodes
 boolean expandRow(TreePath path, boolean openAll)
          Opens the row so its children are visible.
 TreeViewColumn getColumn(int position)
          Gets the column at the given position in the tree view.
 TreeViewColumn getCursorColumn()
          Returns the current column
 TreePath getCursorPath()
          Returns the current path
 Adjustment getHAdjustment()
          Gets the GtkAdjustment currently being used for the horizontal aspect.
 TreeModel getModel()
          Returns the model associated with this tree.
 boolean getRowExpanded(TreePath path)
          Returns TRUE if the node pointed to by path is expanded.
 TreeSelection getSelection()
          Gets the TreeSelection associated with this widget
static Type getType()
          Retrieve the runtime type used by the GLib library.
 Adjustment getVAdjustment()
          Gets the Adjustment currently being used for the vertical aspect.
 int insertColumn(TreeViewColumn column, int position)
          This inserts the column into the tree_view at position.
 void moveColumn(TreeViewColumn column, TreeViewColumn baseColumn)
          Moves column to be after to baseColumn.
 int removeColumn(TreeViewColumn column)
          Removes column from tree_view.
 void scrollToCell(TreePath path)
          Moves the alignments of the view to the position specified by path.
 void scrollToCell(TreePath path, TreeViewColumn column)
          Moves the alignments of the view to the position specified by column and path.
 void scrollToCell(TreePath path, TreeViewColumn column, double rowAlign, double colAlign)
          Moves the alignments of the view to the position specified by column and path.
 void scrollToCell(TreeViewColumn column)
           
 void setAlternateRowColor(boolean setting)
          This function tells GTK+ that the user interface for your application requires users to read across tree rows and associate cells with one another.
 void setCursor(TreePath path, TreeViewColumn focusColumn, boolean startEditing)
          Sets the current keyboard focus to be at path, and selects it.
 void setEnableSearch(boolean enableSearch)
          If enable search is set, then the user can type in text to search through the tree interactively.
 void setExpanderColumn(TreeViewColumn column)
          Sets the column to draw the expander arrow at.
 void setHAdjustment(Adjustment hadj)
          Sets the Adjustment for the current horizontal aspect.
 void setHeadersClickable(boolean setting)
          Allow the column title buttons to be clicked.
 void setHeadersVisible(boolean headersVisible)
          Sets the the visibility state of the headers.
 void setModel(TreeModel model)
          Sets the model for a GtkTreeView.
 void setReorderable(boolean reorderable)
          This function is a convenience function to allow you to reorder models that support the DragSourceIface and the DragDestIface.
 void setSearchColumn(TreeViewColumn column)
          Sets column as the column where the interactive search code should search in.
 void setVAdjustment(Adjustment vadj)
          Sets the Adjustment for the current vertical aspect.
 
Methods inherited from class org.gnu.gtk.Container
add, addListener, getBorderWidth, getEventListenerClass, getEventType, getResizeMode, remove, removeListener, resizeChildren, setBorderWidth, setResizeMode
 
Methods inherited from class org.gnu.gtk.Widget
activate, addListener, addListener, addListener, addListener, addListener, addListener, createContext, createLayout, destroy, draw, drawArea, drawArea, getAccessible, getColormap, getContext, getModifierStyle, getName, getParent, getParentWindow, getPointer, getSensitive, getStyle, getToplevel, grabDefault, grabFocus, hasFocus, hide, hideAll, intersect, isAncestor, makeWidget, modifyStyle, popColormap, pushColormap, realize, removeListener, removeListener, removeListener, removeListener, removeListener, removeListener, reparent, setBackgroundColor, setBaseColor, setColormap, setDoubleBuffered, setDragDestination, setDragSource, setFont, setForegroundColor, setMinimumSize, setName, setNoDragDestination, setNoDragSource, setSensitive, setTextColor, shapeCombineMask, show, showAll
 
Methods inherited from class org.gnu.glib.GObject
addEventHandler, addEventHandler, addEventHandler, addEventHandler, addEventHandler, addEventHandler, equals, getData, getHandle, removeEventHandler, setData
 
Methods inherited from class java.lang.Object
getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

TreeView

public TreeView(int handle)
Creates a new tree view from a native handle


TreeView

public TreeView(TreeModel model)
Creates a new TreeView Widget with the initial model set

Method Detail

getModel

public TreeModel getModel()
Returns the model associated with this tree.


appendColumn

public int appendColumn(TreeViewColumn column)
Appends column to the list of columns.

Parameters:
column - The GtkTreeViewColumn to add.
Returns:
The number of columns in tree_view after appending.

insertColumn

public int insertColumn(TreeViewColumn column,
                        int position)
This inserts the column into the tree_view at position. If position is -1, then the column is inserted at the end.

Parameters:
column - The GtkTreeViewColumn to be inserted.
position - The position to insert column in.
Returns:
The number of columns in tree_view after insertion.

removeColumn

public int removeColumn(TreeViewColumn column)
Removes column from tree_view.

Parameters:
column - The GtkTreeViewColumn to remove.
Returns:
The number of columns in tree_view after removing.

getSelection

public TreeSelection getSelection()
Gets the TreeSelection associated with this widget


getHAdjustment

public Adjustment getHAdjustment()
Gets the GtkAdjustment currently being used for the horizontal aspect.

Returns:
A GtkAdjustment object, or NULL if none is currently being used.

setHAdjustment

public void setHAdjustment(Adjustment hadj)
Sets the Adjustment for the current horizontal aspect.


getVAdjustment

public Adjustment getVAdjustment()
Gets the Adjustment currently being used for the vertical aspect.


setVAdjustment

public void setVAdjustment(Adjustment vadj)
Sets the Adjustment for the current vertical aspect.


setHeadersVisible

public void setHeadersVisible(boolean headersVisible)
Sets the the visibility state of the headers.

Parameters:
headersVisible - TRUE if the headers are visibl

setHeadersClickable

public void setHeadersClickable(boolean setting)
Allow the column title buttons to be clicked.

Parameters:
setting - TRUE if the columns are clickable.

setAlternateRowColor

public void setAlternateRowColor(boolean setting)
This function tells GTK+ that the user interface for your application requires users to read across tree rows and associate cells with one another. By default, GTK+ will then render the tree with alternating row colors. Do not use it just because you prefer the appearance of the ruled tree; that's a question for the theme. Some themes will draw tree rows in alternating colors even when rules are turned off, and users who prefer that appearance all the time can choose those themes. You should call this function only as a semantic hint to the theme engine that your tree makes alternating colors useful from a functional standpoint (since it has lots of columns, generally).

Parameters:
setting - TRUE if the tree requires reading across rows

getColumn

public TreeViewColumn getColumn(int position)
Gets the column at the given position in the tree view.

Returns:
The TreeViewColumn, or null if the position is outside the range of columns.

moveColumn

public void moveColumn(TreeViewColumn column,
                       TreeViewColumn baseColumn)
Moves column to be after to baseColumn. If baseColumn is NULL, then column is placed in the first position.

Parameters:
column - The GtkTreeViewColumn to be moved.
baseColumn - The GtkTreeViewColumn to be moved relative to, or NULL.

setExpanderColumn

public void setExpanderColumn(TreeViewColumn column)
Sets the column to draw the expander arrow at. If column is NULL, then the expander arrow is always at the first visible column.

Parameters:
column - NULL, or the column to draw the expander arrow at.

scrollToCell

public void scrollToCell(TreePath path,
                         TreeViewColumn column,
                         double rowAlign,
                         double colAlign)
Moves the alignments of the view to the position specified by column and path. . rowAlign determines where the row is placed, and colAlign determines where column is placed. Both are expected to be between 0.0 and 1.0. 0.0 means left/top alignment, 1.0 means right/bottom alignment, 0.5 means center.

Parameters:
path - The path of the row to move to
column - The TreeViewColumn to move horizontally to
rowAlign - The vertical alignment of the row specified by path.
colAlign - : The horizontal alignment of the column specified by column.

scrollToCell

public void scrollToCell(TreePath path,
                         TreeViewColumn column)
Moves the alignments of the view to the position specified by column and path.

Parameters:
path - The path of the row to move to
column - The TreeViewColumn to move horizontally to

scrollToCell

public void scrollToCell(TreeViewColumn column)

scrollToCell

public void scrollToCell(TreePath path)
Moves the alignments of the view to the position specified by path.

Parameters:
path - The path of the row to move to, or NULL.

setCursor

public void setCursor(TreePath path,
                      TreeViewColumn focusColumn,
                      boolean startEditing)
Sets the current keyboard focus to be at path, and selects it. This is useful when you want to focus the user's attention on a particular row. If column is specified, and startEditing is TRUE, then editing should be started in the specified cell. This function is often followed by Widget.grabFocus() in order to give keyboard focus to the widget. Please note that editing can only happen when the widget is realized.

Parameters:
path - A TreePath
focusColumn - A TreeViewColumn, or NULL
startEditing - TRUE if the specified cell should start being edited.

getCursorPath

public TreePath getCursorPath()
Returns the current path


getCursorColumn

public TreeViewColumn getCursorColumn()
Returns the current column


activateCell

public void activateCell(TreePath path,
                         TreeViewColumn column)
Activates the cell determined by path and column.

Parameters:
path - The TreePath to be activated.
column - The TreeViewColumn to be activated.

expandAll

public void expandAll()
Recursively expands all nodes


collapseAll

public void collapseAll()
Recursively collapses all visible, expanded nodes.


expandRow

public boolean expandRow(TreePath path,
                         boolean openAll)
Opens the row so its children are visible.

Parameters:
path - Path to a row
openAll - Whether to recursively expand, or just expand immediate children
Returns:
TRUE if the row existed and had children

collapseRow

public boolean collapseRow(TreePath path)
Collapses a row (hides its child rows, if they exist).

Parameters:
path - Path to a row in the view
Returns:
TRUE if the row was collapsed.

getRowExpanded

public boolean getRowExpanded(TreePath path)
Returns TRUE if the node pointed to by path is expanded.

Parameters:
path - A TreePath to test expansion state.
Returns:
TRUE if path is expanded.

setReorderable

public void setReorderable(boolean reorderable)
This function is a convenience function to allow you to reorder models that support the DragSourceIface and the DragDestIface. Both TreeStore and ListStore support these. If reorderable is TRUE, then the user can reorder the model by dragging and dropping rows. The developer can listen to these changes by adding listeners.

This function does not give you any degree of control over the order -- any reorderering is allowed. If more control is needed, you should probably handle drag and drop manually.

Parameters:
reorderable - TRUE, if the tree can be reordered.

setModel

public void setModel(TreeModel model)
Sets the model for a GtkTreeView. If the TreeView already has a model set, it will remove it before setting the new model. If model is NULL, then it will unset the old model.

Parameters:
model - the new model for the TreeView

setEnableSearch

public void setEnableSearch(boolean enableSearch)
If enable search is set, then the user can type in text to search through the tree interactively.

Parameters:
enableSearch - TRUE, if the user can search interactively

setSearchColumn

public void setSearchColumn(TreeViewColumn column)
Sets column as the column where the interactive search code should search in. Additionally, turns on interactive searching.

Parameters:
column - The column to search in

getType

public static Type getType()
Retrieve the runtime type used by the GLib library.


Please send any bug reports, comments, or suggestions for the API or documentation to java-gnome-developer@lists.sf.net