Package org.eclipse.jface.viewers

Class AbstractTreeViewer

  • All Implemented Interfaces:
    IInputProvider, IInputSelectionProvider, IPostSelectionProvider, ISelectionProvider
    Direct Known Subclasses:
    TreeViewer
    public abstract class AbstractTreeViewer
extends ColumnViewer
    Abstract base implementation for tree-structure-oriented viewers (trees and table trees).

    Nodes in the tree can be in either an expanded or a collapsed state, depending on whether the children on a node are visible. This class introduces public methods for controlling the expanding and collapsing of nodes.

    As of 3.2, AbstractTreeViewer supports multiple equal elements (each with a different parent chain) in the tree. This support requires that clients enable the element map by calling setUseHashlookup(true).

    Content providers for abstract tree viewers must implement one of the interfaces ITreeContentProvider or (as of 3.2, to support multiple equal elements) ITreePathContentProvider.

    This class is not intended to be subclassed outside of the JFace viewers framework.

    See Also:
    TreeViewer

    • Constructor Detail

      • AbstractTreeViewer

        protected AbstractTreeViewer()
        Creates an abstract tree viewer. The viewer has no input, no content provider, a default label provider, no sorter, no filters, and has auto-expand turned off.

    • Method Detail

      • add

        public void add​(Object parentElementOrTreePath,
                Object... childElements)
        Adds the given child elements to this viewer as children of the given parent element. If this viewer does not have a sorter, the elements are added at the end of the parent's list of children in the order given; otherwise, the elements are inserted at the appropriate positions. If a child already exists under the given parent, the child gets refreshed and not added twice.

        This method should be called (by the content provider) when elements have been added to the model, in order to cause the viewer to accurately reflect the model. This method only affects the viewer, not the model.

        Parameters:
        parentElementOrTreePath - the parent element
        childElements - the child elements to add

      • internalFindItems

        protected final Widget[] internalFindItems​(Object parentElementOrTreePath)
        Find the items for the given element of tree path
        Parameters:
        parentElementOrTreePath - the element or tree path
        Returns:
        the items for that element
        Since:
        3.3

      • internalAdd

        protected void internalAdd​(Widget widget,
                           Object parentElementOrTreePath,
                           Object[] childElements)
        Adds the given child elements to this viewer as children of the given parent element.

        EXPERIMENTAL. Not to be used except by JDT. This method was added to support JDT's explorations into grouping by working sets. This method cannot be removed without breaking binary backwards compatibility, but should not be called by clients.

        Parameters:
        widget - the widget for the parent element
        parentElementOrTreePath - the parent element
        childElements - the child elements to add
        Since:
        3.1

      • indexForElement

        protected int indexForElement​(Widget parent,
                              Object element)
        Returns the index where the item should be inserted.
        Parameters:
        parent - The parent widget the element will be inserted into.
        element - The element to insert.
        Returns:
        the index of the element

      • getSortedChildren

        protected Object[] getSortedChildren​(Object parentElementOrTreePath)
        Description copied from class: StructuredViewer
        Returns the sorted and filtered set of children of the given element. The resulting array must not be modified, as it may come directly from the model's internal state.
        Overrides:
        getSortedChildren in class StructuredViewer
        Parameters:
        parentElementOrTreePath - the parent element
        Returns:
        a sorted and filtered array of child elements

      • add

        public void add​(Object parentElementOrTreePath,
                Object childElement)
        Adds the given child element to this viewer as a child of the given parent element. If this viewer does not have a sorter, the element is added at the end of the parent's list of children; otherwise, the element is inserted at the appropriate position. If the child already exists under the given parent, the child gets refreshed and not added twice.

        This method should be called (by the content provider) when a single element has been added to the model, in order to cause the viewer to accurately reflect the model. This method only affects the viewer, not the model. Note that there is another method for efficiently processing the simultaneous addition of multiple elements.

        Parameters:
        parentElementOrTreePath - the parent element or path
        childElement - the child element

      • addSelectionListener

        @Deprecated
protected void addSelectionListener​(Control control,
                                    SelectionListener listener)
        Deprecated.
        Adds the given SWT selection listener to the given SWT control.
        Parameters:
        control - the SWT control
        listener - the SWT selection listener

      • addTreeListener

        public void addTreeListener​(ITreeViewerListener listener)
        Adds a listener for expand and collapse events in this viewer. Has no effect if an identical listener is already registered.
        Parameters:
        listener - a tree viewer listener

      • addTreeListener

        protected abstract void addTreeListener​(Control control,
                                        TreeListener listener)
        Adds the given SWT tree listener to the given SWT control.
        Parameters:
        control - the SWT control
        listener - the SWT tree listener

      • associate

        protected void associate​(Object element,
                         Item item)
        Description copied from class: StructuredViewer
        Associates the given element with the given widget. Sets the given item's data to be the element, and maps the element to the item in the element map (if enabled).
        Overrides:
        associate in class StructuredViewer
        Parameters:
        element - the element
        item - the widget

      • collapseAll

        public void collapseAll()
        Collapses all nodes of the viewer's tree, starting with the root. This method is equivalent to collapseToLevel(ALL_LEVELS).

      • collapseToLevel

        public void collapseToLevel​(Object elementOrTreePath,
                            int level)
        Collapses the subtree rooted at the given element or tree path to the given level.

        Note that the default implementation of this method does turn redraw off via this operation via a call to setRedraw

        Parameters:
        elementOrTreePath - the element or tree path
        level - non-negative level, or ALL_LEVELS to collapse all levels of the tree

      • createChildren

        protected void createChildren​(Widget widget)
        Creates all children for the given widget.

        The default implementation of this framework method assumes that widget.getData() returns the element corresponding to the node. Note: the node is not visually expanded! You may have to call parent.setExpanded(true).

        Parameters:
        widget - the widget

      • createTreeItem

        protected void createTreeItem​(Widget parent,
                              Object element,
                              int index)
        Creates a single item for the given parent and synchronizes it with the given element.
        Parameters:
        parent - the parent widget
        element - the element
        index - if non-negative, indicates the position to insert the item into its parent

      • disassociate

        protected void disassociate​(Item item)
        The AbstractTreeViewer implementation of this method also recurses over children of the corresponding element.
        Overrides:
        disassociate in class StructuredViewer
        Parameters:
        item - the widget

      • doFindInputItem

        protected Widget doFindInputItem​(Object element)
        Description copied from class: StructuredViewer
        Returns the widget in this viewer's control which represents the given element if it is the viewer's input.

        This method is internal to the framework; subclassers should not call this method.

        Specified by:
        doFindInputItem in class StructuredViewer
        Parameters:
        element - the element to find the representing widget for
        Returns:
        the corresponding widget, or null if none

      • doFindItem

        protected Widget doFindItem​(Object element)
        Description copied from class: StructuredViewer
        Returns the widget in this viewer's control which represent the given element. This method searches all the children of the input element.

        This method is internal to the framework; subclassers should not call this method.

        Specified by:
        doFindItem in class StructuredViewer
        Parameters:
        element - the element to find the representing widget for
        Returns:
        the corresponding widget, or null if none

      • doUpdateItem

        protected void doUpdateItem​(Item item,
                            Object element)
        Copies the attributes of the given element into the given SWT item.
        Parameters:
        item - the SWT item
        element - the element

      • isSameSelection

        protected boolean isSameSelection​(List<Item> items,
                                  Item[] current)
        Returns true if the given list and array of items refer to the same model elements. Order is unimportant.

        This method is not intended to be overridden by subclasses.

        Parameters:
        items - the list of items
        current - the array of items
        Returns:
        true if the refer to the same elements, false otherwise
        Since:
        3.1 in TreeViewer, moved to AbstractTreeViewer in 3.3

      • doUpdateItem

        protected void doUpdateItem​(Widget widget,
                            Object element,
                            boolean fullMap)
        Description copied from class: StructuredViewer
        Copies the attributes of the given element into the given SWT item. The element map is updated according to the value of fullMap. If fullMap is true then the current mapping from element to widgets is removed and the new mapping is added. If full map is false then only the new map gets installed. Installing only the new map is necessary in cases where only the order of elements changes but not the set of elements.

        This method is internal to the framework; subclassers should not call this method.

        Specified by:
        doUpdateItem in class StructuredViewer
        Parameters:
        widget - widget item to update
        element - the element to represent
        fullMap - true if mappings are added and removed, and false if only the new map gets installed

      • expandAll

        public void expandAll()
        Expands all nodes of the viewer's tree, starting with the root. This method is equivalent to expandToLevel(ALL_LEVELS).

      • expandAll

        public void expandAll​(boolean disableRedraw)
        Expands all nodes of the viewer's tree, starting with the root. This method is equivalent to expandToLevel(ALL_LEVELS).
        Parameters:
        disableRedraw - true when drawing operations should be disabled during expansion.
        Since:
        3.14

      • expandToLevel

        public void expandToLevel​(int level)
        Expands the root of the viewer's tree to the given level.
        Parameters:
        level - non-negative level, or ALL_LEVELS to expand all levels of the tree

      • expandToLevel

        public void expandToLevel​(int level,
                          boolean disableRedraw)
        Expands the root of the viewer's tree to the given level.
        Parameters:
        level - non-negative level, or ALL_LEVELS to expand all levels of the tree
        disableRedraw - true when drawing operations should be disabled during expansion. true when drawing operations should be enabled during expansion. Prefer using true as this results in a faster UI
        Since:
        3.14

      • expandToLevel

        public void expandToLevel​(Object elementOrTreePath,
                          int level)
        Expands all ancestors of the given element or tree path so that the given element becomes visible in this viewer's tree control, and then expands the subtree rooted at the given element to the given level.
        Parameters:
        elementOrTreePath - the element
        level - non-negative level, or ALL_LEVELS to expand all levels of the tree

      • expandToLevel

        public void expandToLevel​(Object elementOrTreePath,
                          int level,
                          boolean disableRedraw)
        Expands all ancestors of the given element or tree path so that the given element becomes visible in this viewer's tree control, and then expands the subtree rooted at the given element to the given level.
        Parameters:
        elementOrTreePath - the element
        level - non-negative level, or ALL_LEVELS to expand all levels of the tree
        disableRedraw - true when drawing operations should be disabled during expansion. false when drawing operations should be enabled during expansion. Prefer true as this results in a faster UI.
        Since:
        3.14

      • getAutoExpandLevel

        public int getAutoExpandLevel()
        Returns the auto-expand level.
        Returns:
        non-negative level, or ALL_LEVELS if all levels of the tree are expanded automatically
        See Also:
        setAutoExpandLevel(int)

      • getChildren

        protected abstract Item[] getChildren​(Widget widget)
        Returns the SWT child items for the given SWT widget.
        Parameters:
        widget - the widget
        Returns:
        the child items

      • getChild

        protected Item getChild​(Widget widget,
                        int index)
        Get the child for the widget at index. Note that the default implementation is not very efficient and should be overridden if this class is implemented.
        Parameters:
        widget - the widget to check
        index - the index of the widget
        Returns:
        Item or null if widget is not a type that can contain items.
        Throws:
        ArrayIndexOutOfBoundsException - if the index is not valid.
        Since:
        3.1

      • getExpanded

        protected abstract boolean getExpanded​(Item item)
        Returns whether the given SWT item is expanded or collapsed.
        Parameters:
        item - the item
        Returns:
        true if the item is considered expanded and false if collapsed

      • getExpandedElements

        public Object[] getExpandedElements()
        Returns a list of elements corresponding to expanded nodes in this viewer's tree, including currently hidden ones that are marked as expanded but are under a collapsed ancestor.

        This method is typically used when preserving the interesting state of a viewer; setExpandedElements is used during the restore.

        Returns:
        the array of expanded elements
        See Also:
        setExpandedElements(java.lang.Object...)

      • getExpandedState

        public boolean getExpandedState​(Object elementOrTreePath)
        Returns whether the node corresponding to the given element or tree path is expanded or collapsed.
        Parameters:
        elementOrTreePath - the element
        Returns:
        true if the node is expanded, and false if collapsed

      • getItemCount

        protected abstract int getItemCount​(Control control)
        Returns the number of child items of the given SWT control.
        Parameters:
        control - the control
        Returns:
        the number of children

      • getItemCount

        protected abstract int getItemCount​(Item item)
        Returns the number of child items of the given SWT item.
        Parameters:
        item - the item
        Returns:
        the number of children

      • getItems

        protected abstract Item[] getItems​(Item item)
        Returns the child items of the given SWT item.
        Parameters:
        item - the item
        Returns:
        the child items

      • getNextItem

        protected Item getNextItem​(Item item,
                           boolean includeChildren)
        Returns the item after the given item in the tree, or null if there is no next item.
        Parameters:
        item - the item
        includeChildren - true if the children are considered in determining which item is next, and false if subtrees are ignored
        Returns:
        the next item, or null if none

      • getParentItem

        protected abstract Item getParentItem​(Item item)
        Returns the parent item of the given item in the tree, or null if there is no parent item.
        Parameters:
        item - the item
        Returns:
        the parent item, or null if none

      • getPreviousItem

        protected Item getPreviousItem​(Item item)
        Returns the item before the given item in the tree, or null if there is no previous item.
        Parameters:
        item - the item
        Returns:
        the previous item, or null if none

      • getRawChildren

        protected Object[] getRawChildren​(Object parentElementOrTreePath)
        Description copied from class: StructuredViewer
        Returns the children of the given parent without sorting and filtering them. The resulting array must not be modified, as it may come directly from the model's internal state.

        Returns an empty array if the given parent is null.

        Overrides:
        getRawChildren in class ColumnViewer
        Parameters:
        parentElementOrTreePath - the parent element
        Returns:
        the child elements

      • getSelection

        protected abstract Item[] getSelection​(Control control)
        Returns all selected items for the given SWT control.
        Parameters:
        control - the control
        Returns:
        the list of selected items

      • handleDoubleSelect

        protected void handleDoubleSelect​(SelectionEvent event)
        Description copied from class: StructuredViewer
        Handles a double-click select event from the widget.

        This method is internal to the framework; subclassers should not call this method.

        Overrides:
        handleDoubleSelect in class StructuredViewer
        Parameters:
        event - the SWT selection event

      • handleTreeCollapse

        protected void handleTreeCollapse​(TreeEvent event)
        Handles a tree collapse event from the SWT widget.
        Parameters:
        event - the SWT tree event

      • handleTreeExpand

        protected void handleTreeExpand​(TreeEvent event)
        Handles a tree expand event from the SWT widget.
        Parameters:
        event - the SWT tree event

      • hookControl

        protected void hookControl​(Control control)
        Description copied from class: ContentViewer
        Adds event listener hooks to the given control.

        All subclasses must call this method when their control is first established.

        The ContentViewer implementation of this method hooks dispose events for the given control. Subclasses may override if they need to add other control hooks; however, super.hookControl must be invoked.

        Overrides:
        hookControl in class ColumnViewer
        Parameters:
        control - the control

      • inputChanged

        protected void inputChanged​(Object input,
                            Object oldInput)
        Description copied from class: Viewer
        Internal hook method called when the input to this viewer is initially set or subsequently changed.

        The default implementation does nothing. Subclassers may override this method to do something when a viewer's input is set. A typical use is populate the viewer.

        Overrides:
        inputChanged in class Viewer
        Parameters:
        input - the new input of this viewer, or null if none
        oldInput - the old input element or null if there was previously no input

      • internalInitializeTree

        protected void internalInitializeTree​(Control tree)
        Initializes the tree with root items, expanding to the appropriate level if necessary.
        Parameters:
        tree - the tree control
        Since:
        3.3

      • internalCollapseToLevel

        protected void internalCollapseToLevel​(Widget widget,
                                       int level)
        Recursively collapses the subtree rooted at the given widget to the given level.
        Parameters:
        widget - the widget
        level - non-negative level, or ALL_LEVELS to collapse all levels of the tree

      • internalExpand

        protected Widget internalExpand​(Object elementOrPath,
                                boolean expand)
        Tries to create a path of tree items for the given element or tree path. This method recursively walks up towards the root of the tree and in the case of an element (rather than a tree path) assumes that getParent returns the correct parent of an element.
        Parameters:
        elementOrPath - the element
        expand - true if all nodes on the path should be expanded, and false otherwise
        Returns:
        Widget

      • getParentElement

        protected Object getParentElement​(Object elementOrTreePath)
        This method takes a tree path or an element. If the argument is not a tree path, returns the parent of the given element or null if the parent is not known. If the argument is a tree path with more than one segment, returns its parent tree path, otherwise returns null.
        Parameters:
        elementOrTreePath - the element or path to find parent for
        Returns:
        the parent element, or parent path, or null
        Since:
        3.2

      • internalGetWidgetToSelect

        protected Widget internalGetWidgetToSelect​(Object elementOrTreePath)
        Returns the widget to be selected for the given element or tree path.
        Parameters:
        elementOrTreePath - the element or tree path to select
        Returns:
        the widget to be selected, or null if not found
        Since:
        3.1

      • internalExpandToLevel

        protected void internalExpandToLevel​(Widget widget,
                                     int level)
        Recursively expands the subtree rooted at the given widget to the given level.

        Note that the default implementation of this method does not call setRedraw.

        Parameters:
        widget - the widget
        level - non-negative level, or ALL_LEVELS to collapse all levels of the tree

      • internalRefresh

        protected void internalRefresh​(Object element,
                               boolean updateLabels)
        Description copied from class: StructuredViewer
        Refreshes this viewer starting at the given element. Labels are updated as described in refresh(boolean updateLabels).

        The default implementation simply calls internalRefresh(element), ignoring updateLabels.

        If this method is overridden to do the actual refresh, then internalRefresh(Object element) should simply call internalRefresh(element, true).

        Overrides:
        internalRefresh in class StructuredViewer
        Parameters:
        element - the element
        updateLabels - true to update labels for existing elements, false to only update labels as needed, assuming that labels for existing elements are unchanged.

      • internalRefresh

        protected void internalRefresh​(Widget widget,
                               Object element,
                               boolean doStruct,
                               boolean updateLabels)
        Refreshes the tree starting at the given widget.

        EXPERIMENTAL. Not to be used except by JDT. This method was added to support JDT's explorations into grouping by working sets. This method cannot be removed without breaking binary backwards compatibility, but should not be called by clients.

        Parameters:
        widget - the widget
        element - the element
        doStruct - true if structural changes are to be picked up, and false if only label provider changes are of interest
        updateLabels - true to update labels for existing elements, false to only update labels as needed, assuming that labels for existing elements are unchanged.
        Since:
        3.1

      • internalRemove

        protected void internalRemove​(Object[] elementsOrPaths)
        Removes the given elements from this viewer.

        EXPERIMENTAL. Not to be used except by JDT. This method was added to support JDT's explorations into grouping by working sets. This method cannot be removed without breaking binary backwards compatibility, but should not be called by clients.

        Parameters:
        elementsOrPaths - the elements or element paths to remove
        Since:
        3.1

      • internalRemove

        protected void internalRemove​(Object parent,
                              Object[] elements)
        Removes the given elements from this viewer, whenever those elements appear as children of the given parent.
        Parameters:
        parent - the parent element
        elements - the elements to remove
        Since:
        3.1

      • isExpandable

        public boolean isExpandable​(Object elementOrTreePath)
        Return whether the tree node representing the given element or path can be expanded. Clients should query expandability by path if the viewer's content provider is an ITreePathContentProvider.

        The default implementation of this framework method calls hasChildren on this viewer's content provider. It may be overridden if necessary.

        Parameters:
        elementOrTreePath - the element or path
        Returns:
        true if the tree node representing the given element can be expanded, or false if not
        See Also:
        setExpandPreCheckFilters(boolean)

      • labelProviderChanged

        protected void labelProviderChanged()
        Description copied from class: ContentViewer
        Notifies that the label provider has changed.

        The ContentViewer implementation of this method calls refresh(). Subclasses may reimplement or extend.

        Overrides:
        labelProviderChanged in class ContentViewer

      • newItem

        protected abstract Item newItem​(Widget parent,
                                int style,
                                int index)
        Creates a new item.
        Parameters:
        parent - the parent widget
        style - SWT style bits
        index - if non-negative, indicates the position to insert the item into its parent
        Returns:
        the newly-created item

      • remove

        public void remove​(Object... elementsOrTreePaths)
        Removes the given elements from this viewer. The selection is updated if required.

        This method should be called (by the content provider) when elements have been removed from the model, in order to cause the viewer to accurately reflect the model. This method only affects the viewer, not the model.

        Parameters:
        elementsOrTreePaths - the elements to remove

      • remove

        public void remove​(Object parent,
                   Object... elements)
        Removes the given elements from this viewer whenever they appear as children of the given parent element. If the given elements also appear as children of some other parent, the other parent will remain unchanged. The selection is updated if required.

        This method should be called (by the content provider) when elements have been removed from the model, in order to cause the viewer to accurately reflect the model. This method only affects the viewer, not the model.

        Parameters:
        parent - the parent of the elements to remove
        elements - the elements to remove
        Since:
        3.2

      • remove

        public void remove​(Object elementsOrTreePaths)
        Removes the given element from the viewer. The selection is updated if necessary.

        This method should be called (by the content provider) when a single element has been removed from the model, in order to cause the viewer to accurately reflect the model. This method only affects the viewer, not the model. Note that there is another method for efficiently processing the simultaneous removal of multiple elements.

        Parameters:
        elementsOrTreePaths - the element

      • removeAll

        protected abstract void removeAll​(Control control)
        Removes all items from the given control.
        Parameters:
        control - the control

      • removeTreeListener

        public void removeTreeListener​(ITreeViewerListener listener)
        Removes a listener for expand and collapse events in this viewer. Has no effect if an identical listener is not registered.
        Parameters:
        listener - a tree viewer listener

      • reveal

        public void reveal​(Object elementOrTreePath)
        This implementation of reveal() reveals the given element or tree path.
        Specified by:
        reveal in class StructuredViewer
        Parameters:
        elementOrTreePath - the element to reveal

      • scrollDown

        public Item scrollDown​(int x,
                       int y)
        Description copied from class: Viewer
        Scrolls the viewer's control down by one item from the given display-relative coordinates. Returns the newly revealed Item, or null if no scrolling occurred or if the viewer doesn't represent an item-based widget.
        Overrides:
        scrollDown in class Viewer
        Parameters:
        x - horizontal coordinate
        y - vertical coordinate
        Returns:
        the item scrolled down to

      • scrollUp

        public Item scrollUp​(int x,
                     int y)
        Description copied from class: Viewer
        Scrolls the viewer's control up by one item from the given display-relative coordinates. Returns the newly revealed Item, or null if no scrolling occurred or if the viewer doesn't represent an item-based widget.
        Overrides:
        scrollUp in class Viewer
        Parameters:
        x - horizontal coordinate
        y - vertical coordinate
        Returns:
        the item scrolled up to

      • setAutoExpandLevel

        public void setAutoExpandLevel​(int level)
        Sets the auto-expand level to be used when the input of the viewer is set using StructuredViewer.setInput(Object). The value 0 means that there is no auto-expand; 1 means that the invisible root element is expanded (since most concrete subclasses do not show the root element, there is usually no practical difference between using the values 0 and 1); 2 means that top-level elements are expanded, but not their children; 3 means that top-level elements are expanded, and their children, but not grandchildren; and so on.

        The value ALL_LEVELS means that all subtrees should be expanded.

        Note that in previous releases, the Javadoc for this method had an off-by one error. See bug 177669 for details.

        Parameters:
        level - non-negative level, or ALL_LEVELS to expand all levels of the tree

      • setExpanded

        protected abstract void setExpanded​(Item item,
                                    boolean expand)
        Sets the expand state of the given item.
        Parameters:
        item - the item
        expand - the expand state of the item

      • setExpandedElements

        public void setExpandedElements​(Object... elements)
        Sets which nodes are expanded in this viewer's tree. The given list contains the elements that are to be expanded; all other nodes are to be collapsed.

        This method is typically used when restoring the interesting state of a viewer captured by an earlier call to getExpandedElements.

        Parameters:
        elements - the array of expanded elements
        See Also:
        getExpandedElements()

      • setExpandedTreePaths

        public void setExpandedTreePaths​(TreePath... treePaths)
        Sets which nodes are expanded in this viewer's tree. The given list contains the tree paths that are to be expanded; all other nodes are to be collapsed.

        This method is typically used when restoring the interesting state of a viewer captured by an earlier call to getExpandedTreePaths.

        Parameters:
        treePaths - the array of expanded tree paths
        Since:
        3.2
        See Also:
        getExpandedTreePaths()

      • setExpandedState

        public void setExpandedState​(Object elementOrTreePath,
                             boolean expanded)
        Sets whether the node corresponding to the given element or tree path is expanded or collapsed.
        Parameters:
        elementOrTreePath - the element
        expanded - true if the node is expanded, and false if collapsed

      • setSelection

        protected abstract void setSelection​(List<Item> items)
        Sets the selection to the given list of items.
        Parameters:
        items - list of items (element type: org.eclipse.swt.widgets.Item)

      • setSelectionToWidget

        protected void setSelectionToWidget​(List v,
                                    boolean reveal)
        This implementation of setSelectionToWidget accepts a list of elements or a list of tree paths.
        Specified by:
        setSelectionToWidget in class StructuredViewer
        Parameters:
        v - list of selected elements (element type: Object) or null if the selection is to be cleared
        reveal - true if the selection is to be made visible, and false otherwise

      • showItem

        protected abstract void showItem​(Item item)
        Shows the given item.
        Parameters:
        item - the item

      • updateChildren

        @Deprecated
protected void updateChildren​(Widget widget,
                              Object parent,
                              Object[] elementChildren)
        Deprecated.
        this is no longer called by the framework
        Updates the tree items to correspond to the child elements of the given parent element. If null is passed for the children, this method obtains them (only if needed).
        Parameters:
        widget - the widget
        parent - the parent element
        elementChildren - the child elements, or null

      • getChildren

        @Deprecated
public Item[] getChildren​(Widget widget,
                          Object[] elementChildren)
        Deprecated.
        This method was inadvertently released as API but is not intended to be called by clients.
        Not to be called by clients. Return the items to be refreshed as part of an update. elementChildren are the new elements.
        Parameters:
        widget - widget to get children for
        elementChildren - unused
        Returns:
        Item[]
        Since:
        3.4

      • updatePlus

        protected void updatePlus​(Item item,
                          Object element)
        Updates the "+"/"-" icon of the tree node from the given element. It calls isExpandable to determine whether an element is expandable.
        Parameters:
        item - the item
        element - the element

      • getVisibleExpandedElements

        public Object[] getVisibleExpandedElements()
        Gets the expanded elements that are visible to the user. An expanded element is only visible if the parent is expanded.
        Returns:
        the visible expanded elements
        Since:
        2.0

      • getTreePathFromItem

        protected TreePath getTreePathFromItem​(Item item)
        Returns the tree path for the given item.
        Parameters:
        item - item to get path for
        Returns:
        TreePath
        Since:
        3.2

      • getSelection

        public ISelection getSelection()
        The AbstractTreeViewer implementation of this method returns the result as an ITreeSelection.

        Call getStructuredSelection() instead to get an instance of ITreeSelection directly.

        Subclasses do not typically override this method, but implement getSelectionFromWidget(List) instead. If they override this method, they should return an ITreeSelection as well.
        Specified by:
        getSelection in interface ISelectionProvider
        Overrides:
        getSelection in class StructuredViewer
        Returns:
        ISelection
        Since:
        3.2

      • setSelectionToWidget

        protected void setSelectionToWidget​(ISelection selection,
                                    boolean reveal)
        Description copied from class: StructuredViewer
        Converts the selection to a List and calls setSelectionToWidget(List, boolean). The selection is expected to be an IStructuredSelection of elements. If not, the selection is cleared.

        Subclasses do not typically override this method, but implement setSelectionToWidget(List, boolean) instead.

        Overrides:
        setSelectionToWidget in class StructuredViewer
        Parameters:
        selection - an IStructuredSelection of elements
        reveal - true to reveal the first element in the selection, or false otherwise

      • getExpandedTreePaths

        public TreePath[] getExpandedTreePaths()
        Returns a list of tree paths corresponding to expanded nodes in this viewer's tree, including currently hidden ones that are marked as expanded but are under a collapsed ancestor.

        This method is typically used when preserving the interesting state of a viewer; setExpandedElements is used during the restore.

        Returns:
        the array of expanded tree paths
        Since:
        3.2
        See Also:
        setExpandedElements(java.lang.Object...)

      • insert

        public void insert​(Object parentElementOrTreePath,
                   Object element,
                   int position)
        Inserts the given element as a new child element of the given parent element at the given position. If this viewer has a sorter, the position is ignored and the element is inserted at the correct position in the sort order.

        This method should be called (by the content provider) when elements have been added to the model, in order to cause the viewer to accurately reflect the model. This method only affects the viewer, not the model.

        Parameters:
        parentElementOrTreePath - the parent element, or the tree path to the parent
        element - the element
        position - a 0-based position relative to the model, or -1 to indicate the last position
        Since:
        3.2

      • getColumnViewerOwner

        protected Widget getColumnViewerOwner​(int columnIndex)
        Description copied from class: ColumnViewer
        Returns the column widget at the given column index.
        Specified by:
        getColumnViewerOwner in class ColumnViewer
        Parameters:
        columnIndex - the column index
        Returns:
        Widget the column widget

      • getItemAt

        protected Item getItemAt​(Point point)
        This implementation of getItemAt(Point) returns null to ensure API backwards compatibility. Subclasses should override.
        Specified by:
        getItemAt in class ColumnViewer
        Parameters:
        point - the widget-relative coordinates
        Returns:
        the Item at the coordinates or null if there is no item at the given coordinates
        Since:
        3.3

      • createViewerEditor

        protected ColumnViewerEditor createViewerEditor()
        This implementation of createViewerEditor() returns null to ensure API backwards compatibility. Subclasses should override.
        Specified by:
        createViewerEditor in class ColumnViewer
        Returns:
        the editor, or null if this viewer does not support editing cell contents.
        Since:
        3.3

      • doGetColumnCount

        protected int doGetColumnCount()
        Returns the number of columns of this viewer.

        Subclasses should overwrite this method, which has a default implementation (returning 0) for API backwards compatility reasons

        Specified by:
        doGetColumnCount in class ColumnViewer
        Returns:
        the number of columns
        Since:
        3.3

      • internalIsInputOrEmptyPath

        protected final boolean internalIsInputOrEmptyPath​(Object elementOrTreePath)
        Returns true if the given object is either the input or an empty tree path.
        Parameters:
        elementOrTreePath - an element which could either be the viewer's input, or a tree path
        Returns:
        true if the given object is either the input or an empty tree path, false otherwise.
        Since:
        3.3

      • getViewerRowFromItem

        protected ViewerRow getViewerRowFromItem​(Widget item)
        Description copied from class: ColumnViewer
        Returns a ViewerRow associated with the given row widget. Implementations may re-use the same instance for different row widgets; callers can only use the viewer row locally and until the next call to this method.
        Specified by:
        getViewerRowFromItem in class ColumnViewer
        Parameters:
        item - the row widget
        Returns:
        ViewerRow a viewer row object

      • setExpandPreCheckFilters

        public void setExpandPreCheckFilters​(boolean checkFilters)
        Instructs isExpandable(Object) to consult filters to more accurately determine if an item can be expanded.

        Setting this value to true will affect performance of the tree viewer.

        To improve performance, by default the tree viewer does not consult filters when determining if a tree node could be expanded.

        Parameters:
        checkFilters - true to instruct tree viewer to consult filters
        Since:
        3.8
        See Also:
        isExpandable(Object)