com.google.gwt.user.client.ui

Class TreeItem

java.lang.Object

com.google.gwt.user.client.ui.UIObject

com.google.gwt.user.client.ui.TreeItem

All Implemented Interfaces:

HasSafeHtml, HasHTML, HasText, HasTreeItems, HasVisibility, IsTreeItem

public class TreeItem
extends UIObject
implements IsTreeItem, HasTreeItems, HasHTML, HasSafeHtml

An item that can be contained within a Tree. Each tree item is assigned a unique DOM id in order to support ARIA. See Accessibility for more information.

Example

public class TreeExample implements EntryPoint {

  @Override
  public void onModuleLoad() {
    // Create a tree with a few items in it.
    TreeItem root = new TreeItem();
    root.setText("root");
    root.addTextItem("item0");
    root.addTextItem("item1");
    root.addTextItem("item2");

    // Add a CheckBox to the tree
    TreeItem item = new TreeItem(new CheckBox("item3"));
    root.addItem(item);

    Tree t = new Tree();
    t.addItem(root);

    // Add it to the root panel.
    RootPanel.get().add(t);
  }
}

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TreeItem.TreeItemImpl Implementation class for TreeItem.
static class	TreeItem.TreeItemImplIE8ToIE10 IE specific implementation class for TreeItem.

Nested classes/interfaces inherited from class com.google.gwt.user.client.ui.UIObject

UIObject.DebugIdImpl, UIObject.DebugIdImplEnabled

Nested classes/interfaces inherited from interface com.google.gwt.user.client.ui.HasTreeItems

HasTreeItems.ForIsWidget

Field Summary

Fields

Modifier and Type	Field and Description
(package private) static int	IMAGE_PAD

Fields inherited from class com.google.gwt.user.client.ui.UIObject

DEBUG_ID_PREFIX, MISSING_ELEMENT_ERROR, SETELEMENT_TWICE_ERROR

Constructor Summary

Constructors

Constructor and Description
TreeItem() Creates an empty tree item.
TreeItem(boolean isRoot) Creates an empty tree item.
TreeItem(SafeHtml html) Constructs a tree item with the given HTML.
TreeItem(Widget widget) Constructs a tree item with the given Widget.

Method Summary

Modifier and Type	Method and Description
void	addItem(IsTreeItem isItem) Adds another item as a child to this one.
TreeItem	addItem(SafeHtml itemHtml) Adds a child tree item containing the specified html.
void	addItem(TreeItem item) Adds another item as a child to this one.
TreeItem	addItem(Widget widget) Adds a child tree item containing the specified widget.
TreeItem	addTextItem(java.lang.String itemText) Adds a child tree item containing the specified text.
(package private) void	addTreeItems(java.util.List<TreeItem> accum)
TreeItem	asTreeItem() Returns the TreeItem aspect of the receiver.
TreeItem	getChild(int index) Gets the child at the specified index.
int	getChildCount() Gets the number of children contained in this item.
int	getChildIndex(TreeItem child) Gets the index of the specified child item.
(package private) java.util.ArrayList<TreeItem>	getChildren()
(package private) Element	getContentElem()
protected Focusable	getFocusable() Returns a suggested Focusable instance to use when this tree item is selected.
protected HasFocus	getFocusableWidget() Deprecated. use getFocusable() instead
java.lang.String	getHTML() Gets this object's contents as HTML.
(package private) Element	getImageElement()
(package private) Element	getImageHolderElement()
TreeItem	getParentItem() Gets this item's parent.
boolean	getState() Gets whether this item's children are displayed.
java.lang.String	getText() Gets this object's text.
java.lang.String	getTitle() Gets the title associated with this object.
Tree	getTree() Gets the tree that contains this item.
java.lang.Object	getUserObject() Gets the user-defined object associated with this item.
Widget	getWidget() Gets the Widget associated with this tree item.
(package private) void	initChildren()
TreeItem	insertItem(int beforeIndex, SafeHtml itemHtml) Inserts a child tree item at the specified index containing the specified html.
void	insertItem(int beforeIndex, TreeItem item) Inserts an item as a child to this one.
TreeItem	insertItem(int beforeIndex, Widget widget) Inserts a child tree item at the specified index containing the specified widget.
TreeItem	insertTextItem(int beforeIndex, java.lang.String itemText) Inserts a child tree item at the specified index containing the specified text.
(package private) boolean	isFullNode()
boolean	isSelected() Determines whether this item is currently selected.
(package private) void	maybeRemoveItemFromParent(TreeItem item) Remove a tree item from its parent if it has one.
protected void	onEnsureDebugId(java.lang.String baseID) Affected Elements: -content = The text or Widget next to the image. -child# = The child at the specified index.
void	remove() Removes this item from its tree.
void	removeItem(IsTreeItem isItem) Removes one of this item's children.
void	removeItem(TreeItem item) Removes one of this item's children.
void	removeItems() Removes all of this item's children.
void	setHTML(SafeHtml html) Sets this object's contents via known-safe HTML.
void	setHTML(java.lang.String html) Sets this object's contents via HTML.
(package private) void	setParentItem(TreeItem parent)
void	setSelected(boolean selected) Selects or deselects this item.
void	setState(boolean open) Sets whether this item's children are displayed.
void	setState(boolean open, boolean fireEvents) Sets whether this item's children are displayed.
void	setText(java.lang.String text) Sets this object's text.
void	setTitle(java.lang.String title) Sets the title associated with this object.
(package private) void	setTree(Tree newTree)
void	setUserObject(java.lang.Object userObj) Sets the user-defined object associated with this item.
void	setWidget(Widget newWidget) Sets the current widget.
(package private) void	updateState(boolean animate, boolean updateTreeSelection)
(package private) void	updateStateRecursive()

Methods inherited from class com.google.gwt.user.client.ui.UIObject

addStyleDependentName, addStyleName, ensureDebugId, ensureDebugId, ensureDebugId, getAbsoluteLeft, getAbsoluteTop, getElement, getOffsetHeight, getOffsetWidth, getStyleElement, getStyleName, getStyleName, getStylePrimaryName, getStylePrimaryName, isVisible, isVisible, removeStyleDependentName, removeStyleName, replaceElement, resolvePotentialElement, setElement, setElement, setHeight, setPixelSize, setSize, setStyleDependentName, setStyleName, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setVisible, setVisible, setWidth, sinkBitlessEvent, sinkEvents, toString, unsinkEvents

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

IMAGE_PAD

static final int IMAGE_PAD

See Also:

Constant Field Values

Constructor Detail

TreeItem

public TreeItem()

Creates an empty tree item.

TreeItem

public TreeItem(SafeHtml html)

Constructs a tree item with the given HTML.

Parameters:

html - the item's HTML

TreeItem

public TreeItem(Widget widget)

Constructs a tree item with the given Widget.

Parameters:

widget - the item's widget

TreeItem

TreeItem(boolean isRoot)

Creates an empty tree item.

Parameters:

isRoot - true if this item is the root of a tree

Method Detail

addItem

public TreeItem addItem(SafeHtml itemHtml)

Adds a child tree item containing the specified html.

Specified by:

addItem in interface HasTreeItems

Parameters:

itemHtml - the item's HTML

Returns:

the item that was added

addItem

public void addItem(TreeItem item)

Adds another item as a child to this one.

Specified by:

addItem in interface HasTreeItems

Parameters:

item - the item to be added

addItem

public void addItem(IsTreeItem isItem)

Adds another item as a child to this one.

Specified by:

addItem in interface HasTreeItems

Parameters:

isItem - the wrapper of item to be added

addItem

public TreeItem addItem(Widget widget)

Adds a child tree item containing the specified widget.

Specified by:

addItem in interface HasTreeItems

Parameters:

widget - the widget to be added

Returns:

the item that was added

addTextItem

public TreeItem addTextItem(java.lang.String itemText)

Adds a child tree item containing the specified text.

Specified by:

addTextItem in interface HasTreeItems

Parameters:

itemText - the text of the item to be added

Returns:

the item that was added

asTreeItem

public TreeItem asTreeItem()

Description copied from interface: IsTreeItem

Returns the TreeItem aspect of the receiver.

Specified by:

asTreeItem in interface IsTreeItem

getChild

public TreeItem getChild(int index)

Gets the child at the specified index.

Parameters:

index - the index to be retrieved

Returns:

the item at that index

getChildCount

public int getChildCount()

Gets the number of children contained in this item.

Returns:

this item's child count.

getChildIndex

public int getChildIndex(TreeItem child)

Gets the index of the specified child item.

Parameters:

child - the child item to be found

Returns:

the child's index, or -1 if none is found

getHTML

public java.lang.String getHTML()

Description copied from interface: HasHTML

Gets this object's contents as HTML.

Specified by:

getHTML in interface HasHTML

Returns:

the object's HTML

getParentItem

public TreeItem getParentItem()

Gets this item's parent.

Returns:

the parent item

getState

public boolean getState()

Gets whether this item's children are displayed.

Returns:

true if the item is open

getText

public java.lang.String getText()

Description copied from interface: HasText

Gets this object's text.

Specified by:

getText in interface HasText

Returns:

the object's text

getTree

public final Tree getTree()

Gets the tree that contains this item.

Returns:

the containing tree

getUserObject

public java.lang.Object getUserObject()

Gets the user-defined object associated with this item.

Returns:

the item's user-defined object

getWidget

public Widget getWidget()

Gets the Widget associated with this tree item.

Returns:

the widget

getTitle

public java.lang.String getTitle()

Description copied from class: UIObject

Gets the title associated with this object. The title is the 'tool-tip' displayed to users when they hover over the object.

Overrides:

getTitle in class UIObject

Returns:

the object's title

setTitle

public void setTitle(java.lang.String title)

Description copied from class: UIObject

Sets the title associated with this object. The title is the 'tool-tip' displayed to users when they hover over the object.

Overrides:

setTitle in class UIObject

Parameters:

title - the object's new title

insertItem

public TreeItem insertItem(int beforeIndex,
                           SafeHtml itemHtml)
                    throws java.lang.IndexOutOfBoundsException

Inserts a child tree item at the specified index containing the specified html.

Parameters:

beforeIndex - the index where the item will be inserted

itemHtml - the item's HTML

Returns:

the item that was added

Throws:

java.lang.IndexOutOfBoundsException - if the index is out of range

insertItem

public void insertItem(int beforeIndex,
                       TreeItem item)
                throws java.lang.IndexOutOfBoundsException

Inserts an item as a child to this one.

Parameters:

beforeIndex - the index where the item will be inserted

item - the item to be added

Throws:

java.lang.IndexOutOfBoundsException - if the index is out of range

insertItem

public TreeItem insertItem(int beforeIndex,
                           Widget widget)
                    throws java.lang.IndexOutOfBoundsException

Inserts a child tree item at the specified index containing the specified widget.

Parameters:

beforeIndex - the index where the item will be inserted

widget - the widget to be added

Returns:

the item that was added

Throws:

java.lang.IndexOutOfBoundsException - if the index is out of range

insertTextItem

public TreeItem insertTextItem(int beforeIndex,
                               java.lang.String itemText)

Inserts a child tree item at the specified index containing the specified text.

Parameters:

beforeIndex - the index where the item will be inserted

itemText - the item's text

Returns:

the item that was added

Throws:

java.lang.IndexOutOfBoundsException - if the index is out of range

isSelected

public boolean isSelected()

Determines whether this item is currently selected.

Returns:

true if it is selected

remove

public void remove()

Removes this item from its tree.

removeItem

public void removeItem(TreeItem item)

Removes one of this item's children.

Specified by:

removeItem in interface HasTreeItems

Parameters:

item - the item to be removed

removeItem

public void removeItem(IsTreeItem isItem)

Removes one of this item's children.

Specified by:

removeItem in interface HasTreeItems

Parameters:

isItem - the wrapper of item to be removed

removeItems

public void removeItems()

Removes all of this item's children.

Specified by:

removeItems in interface HasTreeItems

setHTML

public void setHTML(java.lang.String html)

Description copied from interface: HasHTML

Sets this object's contents via HTML. Use care when setting an object's HTML; it is an easy way to expose script-based security problems. Consider using HasText.setText(String) whenever possible.

Specified by:

setHTML in interface HasHTML

Parameters:

html - the object's new HTML

setHTML

public void setHTML(SafeHtml html)

Description copied from interface: HasSafeHtml

Sets this object's contents via known-safe HTML.

The object will behave exactly the same as when a widget's HasHTML.setHTML(String) method is invoked; however the SafeHtml passed to this method observes the contract that it can be used in an HTML context without causing unsafe script execution. Thus, unlike HasHTML.setHTML(String), using this method cannot result in Cross-Site Scripting security vulnerabilities.

Specified by:

setHTML in interface HasSafeHtml

Parameters:

html - the object's new HTML, represented as a SafeHtml object

setSelected

public void setSelected(boolean selected)

Selects or deselects this item.

Parameters:

selected - true to select the item, false to deselect it

setState

public void setState(boolean open)

Sets whether this item's children are displayed.

Parameters:

open - whether the item is open

setState

public void setState(boolean open,
                     boolean fireEvents)

Sets whether this item's children are displayed.

Parameters:

open - whether the item is open

fireEvents - true to allow open/close events to be

setText

public void setText(java.lang.String text)

Description copied from interface: HasText

Sets this object's text.

Specified by:

setText in interface HasText

Parameters:

text - the object's new text

setUserObject

public void setUserObject(java.lang.Object userObj)

Sets the user-defined object associated with this item.

Parameters:

userObj - the item's user-defined object

setWidget

public void setWidget(Widget newWidget)

Sets the current widget. Any existing child widget will be removed.

Parameters:

newWidget - Widget to set

getFocusable

protected Focusable getFocusable()

Returns a suggested Focusable instance to use when this tree item is selected. The tree maintains focus if this method returns null. By default, if the tree item contains a focusable widget, that widget is returned. Note, the Tree will ignore this value if the user clicked on an input element such as a button or text area when selecting this item.

Returns:

the focusable item

getFocusableWidget

@Deprecated
protected HasFocus getFocusableWidget()

Deprecated. use getFocusable() instead

Returns the widget, if any, that should be focused on if this TreeItem is selected.

Returns:

widget to be focused.

onEnsureDebugId

protected void onEnsureDebugId(java.lang.String baseID)

Affected Elements:

• -content = The text or Widget next to the image.
• -child# = The child at the specified index.

Overrides:

onEnsureDebugId in class UIObject

Parameters:

baseID - the base ID used by the main element

See Also:

UIObject.onEnsureDebugId(String)

addTreeItems

void addTreeItems(java.util.List<TreeItem> accum)

getChildren

java.util.ArrayList<TreeItem> getChildren()

getContentElem

Element getContentElem()

getImageElement

Element getImageElement()

getImageHolderElement

Element getImageHolderElement()

initChildren

void initChildren()

isFullNode

boolean isFullNode()

maybeRemoveItemFromParent

void maybeRemoveItemFromParent(TreeItem item)

Remove a tree item from its parent if it has one.

Parameters:

item - the tree item to remove from its parent

setParentItem

void setParentItem(TreeItem parent)

setTree

void setTree(Tree newTree)

updateState

void updateState(boolean animate,
                 boolean updateTreeSelection)

updateStateRecursive

void updateStateRecursive()