Package com.google.gwt.user.client.ui

Class 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);
  }
}

    • 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

      • 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()