Package org.vaadin.firitin.components

Class Tree<T>

java.lang.Object

com.vaadin.flow.component.Component

com.vaadin.flow.component.Composite<com.vaadin.flow.component.orderedlayout.VerticalLayout>

org.vaadin.firitin.components.Tree<T>

Type Parameters:

T - the type of items listed as nodes of Tree. Use Object if nothing else.

All Implemented Interfaces:

com.vaadin.flow.component.AttachNotifier, com.vaadin.flow.component.DetachNotifier, com.vaadin.flow.component.HasElement, com.vaadin.flow.component.HasStyle, Serializable

@StyleSheet("context://frontend/org/vaadin/firitin/components/tree.css")
public class Tree<T>
extends com.vaadin.flow.component.Composite<com.vaadin.flow.component.orderedlayout.VerticalLayout>

A Tree component to display hierarchical data sets.

Author:

mstahv

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	Tree.ChildrenProvider<T>
static interface	Tree.ItemDecorator<T>	This can be used to further configure the created TreeItem instances.
static interface	Tree.ItemGenerator<T>	Tree.ItemGenerator can be used to customize how to item is shown.
static interface	Tree.ItemIconGenerator<T>	Tree.ItemIconGenerator can be used to customize the icon shown before the label of an item.
static interface	Tree.SelectionListener<T>	A listener to track when the selected node is changed.

Constructor Summary

Constructors

Constructor	Description
Tree()

Method Summary

Modifier and Type	Method	Description
void	addChild(T parent, T item)	Adds child of the node in UI.
void	addItemDecorator(Tree.ItemDecorator<T> decorator)	Adds an Tree.ItemDecorator to further configure TreeItems generated automatically when setItems(List, ChildrenProvider) method is called.
void	addSelectionListener(Tree.SelectionListener<T> listener)	Adds selection listener to nodes.
protected TreeItem	createTreeItem(T item)
void	deselectAllItems()	Deselects all tree items in the UI.
void	editChild(T item)	Edits child in UI.
protected void	fillTree(Tree.ChildrenProvider<T> childrenProvider, T item, TreeItem treeItem)
protected void	fillWithProviders(int level, T item, TreeItem treeItem, Tree.ChildrenProvider... providers)
void	hideChildren(T item)	Hides children of the node in UI.
void	moveChild(T parent, List<T> items, int index, boolean up)	Moves child of the node in UI.
void	removeChild(T parent, T item)	Removes child of the node in UI.
void	removeItemDecorator(Tree.ItemDecorator<T> decorator)
void	removeSelectionListener(Tree.SelectionListener<T> listener)
TreeItem	scrollItemToView(T item)	Scrolls the tree item representing given item to be visible in the UI.
void	selectItem(T item, boolean selected)	Selects (or deselects) the tree item representing given item in the UI.
void	setItemGenerator(Tree.ItemGenerator<T> itemGenerator)	Sets the strategy to generate component for for the items.
void	setItemIconGenerator(Tree.ItemIconGenerator<T> itemIconGenerator)	Sets the strategy to generate icons for the items.
void	setItemLabelGenerator(com.vaadin.flow.component.ItemLabelGenerator<T> itemLabelGenerator)	Sets the strategy to generate label texts for the items.
void	setItems(com.vaadin.flow.data.provider.hierarchy.TreeData<T> treeData, Tree.ChildrenProvider<T> childrenProvider)	Deprecated. Helper to move from TreeGrid usage, in case the TreeData (from Vaadin core) happens to be used to describe the hierarchy.
void	setItems(List<? extends T> roots, Tree.ChildrenProvider<? extends T>... providersForNextLevels)	Sets root items with multiple children providers used to fetch sub-sequent levels.
void	setItems(List<? extends T> rootNodes, Tree.ChildrenProvider<T> childrenProvider)	Sets the root nodes for the tree with a strategy to fetch children for items (recursively).
void	setItems(T root, Tree.ChildrenProvider<? extends T>... providersForNextLevels)	Sets root item with multiple children providers used to fetch sub-sequent levels.
void	setItems(T rootNode, Tree.ChildrenProvider<T> childrenProvider)	Sets the root node for the tree with a strategy to fetch children for items (recursively).
void	showChildren(T item)	Shows children of the node in UI.
void	showChildrenRecursively(T item)	Shows children of the node in UI recursively.
void	styleChild(T item, String styleName, String styleValue)

Methods inherited from class com.vaadin.flow.component.Composite

getChildren, getContent, getElement, initContent

Methods inherited from class com.vaadin.flow.component.Component

addListener, findAncestor, fireEvent, from, get, getEventBus, getId, getListeners, getLocale, getParent, getTranslation, getTranslation, getTranslation, getTranslation, getTranslation, getTranslation, getUI, hasListener, isAttached, isTemplateMapped, isVisible, onAttach, onDetach, onEnabledStateChanged, removeFromParent, scrollIntoView, scrollIntoView, set, setElement, setId, setVisible

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.vaadin.flow.component.AttachNotifier

addAttachListener

Methods inherited from interface com.vaadin.flow.component.DetachNotifier

addDetachListener

Methods inherited from interface com.vaadin.flow.component.HasStyle

addClassName, addClassNames, getClassName, getClassNames, getStyle, hasClassName, removeClassName, removeClassNames, setClassName, setClassName

Constructor Details

Tree

public Tree()

Method Details

setItems

public void setItems(List<? extends T> rootNodes,
 Tree.ChildrenProvider<T> childrenProvider)

Sets the root nodes for the tree with a strategy to fetch children for items (recursively). The nodes will be closed by default and tree structure will be populated lazily when nodes are opened.

Code example:

   List<Dude> rootNodes = getRootNodes();
   dudeTree.setItems(rootNodes, Dude::getSubordinates);
   dudeTree.showChildrenRecursively(rootNodes.get(0));
 

Parameters:

rootNodes - the items to be shown in the Tree at the root level

childrenProvider - the strategy to fetch children from the nodes

setItems

public void setItems(T rootNode,
 Tree.ChildrenProvider<T> childrenProvider)

Sets the root node for the tree with a strategy to fetch children for items (recursively). The nodes will be closed by default and tree structure will be populated lazily when nodes are opened.

Code example:

   dudeTree.setItems(dude, Dude::getSubordinates);
   dudeTree.showChildrenRecursively(dude);
 

Parameters:

rootNode - the item to be shown in the Tree at the root level

childrenProvider - the strategy to fetch children from the nodes

setItems

public void setItems(List<? extends T> roots,
 Tree.ChildrenProvider<? extends T>... providersForNextLevels)

Sets root items with multiple children providers used to fetch sub-sequent levels. This approach is handy if the hierarchy in the Tree comes from class hierarchy (different levels are different Java classes). The T type of the Tree in this case needs to be some common super type of the classes (java.lang.Object if no other exist).

Code example:

  Tree<AbstractPlace> tree = new Tree<>();
  tree.setItemLabelGenerator(AbstractPlace::getName);
  tree.seItems(cities,
          (Tree.ChildrenProvider<City>) c -> c.getStreets(),
          (Tree.ChildrenProvider<Street>) s -> s.getHouses()
   );
 

Parameters:

roots - root items in the Tree

providersForNextLevels - the children providers for next levels of tree, that fetch the children for given item representing the tree node.

setItems

public void setItems(T root,
 Tree.ChildrenProvider<? extends T>... providersForNextLevels)

Sets root item with multiple children providers used to fetch sub-sequent levels. This approach is handy if the hierarchy in the Tree comes from class hierarchy (different levels are different Java classes). The T type of the Tree in this case needs to be some common super type of the classes (java.lang.Object if no other exist).

Code example:

  Tree<AbstractPlace> tree = new Tree<>();
  tree.setItemLabelGenerator(AbstractPlace::getName);
  tree.seItems(city,
          (Tree.ChildrenProvider<City>) c -> c.getStreets(),
          (Tree.ChildrenProvider<Street>) s -> s.getHouses()
   );
 

Parameters:

root - root item in the Tree

providersForNextLevels - the children providers for next levels of tree, that fetch the children for given item representing the tree node.

fillWithProviders

protected void fillWithProviders(int level,
 T item,
 TreeItem treeItem,
 Tree.ChildrenProvider... providers)

setItems

@Deprecated
public void setItems(com.vaadin.flow.data.provider.hierarchy.TreeData<T> treeData,
 Tree.ChildrenProvider<T> childrenProvider)

Deprecated.

Helper to move from TreeGrid usage, in case the TreeData (from Vaadin core) happens to be used to describe the hierarchy.

Parameters:

treeData - d

childrenProvider - p

createTreeItem

protected TreeItem createTreeItem(T item)

fillTree

protected void fillTree(Tree.ChildrenProvider<T> childrenProvider,
 T item,
 TreeItem treeItem)

addItemDecorator

public void addItemDecorator(Tree.ItemDecorator<T> decorator)

Adds an Tree.ItemDecorator to further configure TreeItems generated automatically when setItems(List, ChildrenProvider) method is called.

Parameters:

decorator - the Tree.ItemDecorator

removeItemDecorator

public void removeItemDecorator(Tree.ItemDecorator<T> decorator)

setItemLabelGenerator

public void setItemLabelGenerator(com.vaadin.flow.component.ItemLabelGenerator<T> itemLabelGenerator)

Sets the strategy to generate label texts for the items.

Parameters:

itemLabelGenerator - the ItemLabelGenerator

setItemIconGenerator

public void setItemIconGenerator(Tree.ItemIconGenerator<T> itemIconGenerator)

Sets the strategy to generate icons for the items.

Parameters:

itemIconGenerator - the Tree.ItemIconGenerator

setItemGenerator

public void setItemGenerator(Tree.ItemGenerator<T> itemGenerator)

Sets the strategy to generate component for for the items.

Note that this overrides possibly configured Tree.ItemIconGenerator and ItemLabelGenerator.

Parameters:

itemGenerator - the Tree.ItemGenerator

addSelectionListener

public void addSelectionListener(Tree.SelectionListener<T> listener)

Adds selection listener to nodes.

Parameters:

listener - the listener to be called when selected item changes

removeSelectionListener

public void removeSelectionListener(Tree.SelectionListener<T> listener)

showChildren

public void showChildren(T item)

Shows children of the node in UI. Same as user would click on the caret in the UI.

Parameters:

item - the item whose children should be visible in the UI

showChildrenRecursively

public void showChildrenRecursively(T item)

Shows children of the node in UI recursively. Same as user would click on the caret in the UI.

Parameters:

item - the item whose children should be visible in the UI

hideChildren

public void hideChildren(T item)

Hides children of the node in UI. Same as user would click on the caret in the UI when children are visible.

Parameters:

item - the item whose children should be hidden in the UI

moveChild

public void moveChild(T parent,
 List<T> items,
 int index,
 boolean up)

Moves child of the node in UI.

Parameters:

parent - the parent whose child should be moved in the UI, may be null

items - the items within which one is to be moved

index - the index of the item to be moved

up - True then move up else move down

addChild

public void addChild(T parent,
 T item)

Adds child of the node in UI.

Parameters:

parent - the parent whose child should be added in the UI, may be null

item - the item to be added in the UI

removeChild

public void removeChild(T parent,
 T item)

Removes child of the node in UI.

Parameters:

parent - the parent whose child should be removed in the UI, may be null

item - the item to be removed in the UI

editChild

public void editChild(T item)

Edits child in UI.

Parameters:

item - the item to be edited in the UI

styleChild

public void styleChild(T item,
 String styleName,
 String styleValue)

Parameters:

item - the item to be styled in the UI

styleName - the style property name as camelCase, not null

styleValue - the style property value (if null, the property will be removed)

scrollItemToView

public TreeItem scrollItemToView(T item)

Scrolls the tree item representing given item to be visible in the UI.

Note, the item needs to be visible for the method to work.

Parameters:

item - the item to be shown in the UI

Returns:

The TreeItem for the scroll

selectItem

public void selectItem(T item,
 boolean selected)

Selects (or deselects) the tree item representing given item in the UI.

Parameters:

item - item the item to be selected in the UI

selected - if True then select else deselect

deselectAllItems

public void deselectAllItems()

Deselects all tree items in the UI.