Package com.vaadin.flow.data.provider.hierarchy

Interface HasHierarchicalDataProvider<T>

Type Parameters:

T - the item data type

All Superinterfaces:

Serializable

public interface HasHierarchicalDataProvider<T>
extends Serializable

A generic interface for hierarchical listing components that use a data provider for showing hierarchical data.

Since:

1.1

Author:

Vaadin Ltd

Method Summary

Modifier and Type	Method	Description
HierarchicalDataProvider<T,com.vaadin.flow.function.SerializablePredicate<T>>	getDataProvider()
default TreeData<T>	getTreeData()	Gets the backing TreeData instance of the data provider, if the data provider is a TreeDataProvider.
void	setDataProvider(HierarchicalDataProvider<T,?> hierarchicalDataProvider)	Sets the hierarchical data provider for this listing.
default void	setItems(Collection<T> rootItems, com.vaadin.flow.function.ValueProvider<T,Collection<T>> childItemProvider)	Deprecated. This method will change its behavior in Vaadin 26.
default void	setItems(Stream<T> rootItems, com.vaadin.flow.function.ValueProvider<T,Stream<T>> childItemProvider)	Deprecated. This method will change its behavior in Vaadin 26.
default void	setTreeData(TreeData<T> treeData)	Deprecated. This method will change its behavior in Vaadin 26.

Method Details

getDataProvider

HierarchicalDataProvider<T,com.vaadin.flow.function.SerializablePredicate<T>> getDataProvider()

setTreeData

@Deprecated(since="25.3")
default void setTreeData(TreeData<T> treeData)

Deprecated.

This method will change its behavior in Vaadin 26. It will create a TreeDataProvider with HierarchicalDataProvider.HierarchyFormat.FLATTENED, which may affect TreeGrid methods whose behavior depends on the hierarchy format, such as scrollToIndex. To preserve the current behavior, create a TreeDataProvider manually with HierarchicalDataProvider.HierarchyFormat.NESTED and set it via setDataProvider(HierarchicalDataProvider) instead of using this shorthand method.

Sets a new TreeDataProvider wrapping the given TreeData.

Parameters:

treeData - the tree data to set

getTreeData

default TreeData<T> getTreeData()

Gets the backing TreeData instance of the data provider, if the data provider is a TreeDataProvider.

Returns:

the TreeData instance used by the data provider

Throws:

IllegalStateException - if the type of the data provider is not TreeDataProvider

setItems

@Deprecated(since="25.3")
default void setItems(Collection<T> rootItems,
 com.vaadin.flow.function.ValueProvider<T,Collection<T>> childItemProvider)

Deprecated.

This method will change its behavior in Vaadin 26. It will create a TreeDataProvider with HierarchicalDataProvider.HierarchyFormat.FLATTENED, which may affect TreeGrid methods whose behavior depends on the hierarchy format, such as scrollToIndex. To preserve the current behavior, create a TreeDataProvider manually with HierarchicalDataProvider.HierarchyFormat.NESTED and set it via setDataProvider(HierarchicalDataProvider) instead of using this shorthand method.

Sets the root data items of this component provided as a collection and recursively populates them with child items with the given value provider.

The provided items are wrapped into a TreeDataProvider backed by a flat TreeData structure. The data provider instance is used as a parameter for the setDataProvider(HierarchicalDataProvider) method. It means that the items collection can be accessed later on via getTreeData():

 
 Collection<Person> grandParents = getGrandParents();
 HasHierarchicalDataProvider<Person> treeGrid = new TreeGrid<>();
 treeGrid.setItems(grandParents, Person::getChildren);
 ...

 TreeData<Person> data = treeGrid.getTreeData();
 
 

The returned TreeData instance may be used as-is to add, remove or modify items in the hierarchy. These modifications to the object are not automatically reflected back to the TreeGrid. Items modified should be refreshed with DataProvider.refreshItem(Object) and when adding or removing items DataProvider.refreshAll() should be called.

Parameters:

rootItems - the root items to display, not null

childItemProvider - the value provider used to recursively populate the given root items with child items, not null

setItems

@Deprecated(since="25.3")
default void setItems(Stream<T> rootItems,
 com.vaadin.flow.function.ValueProvider<T,Stream<T>> childItemProvider)

Deprecated.

This method will change its behavior in Vaadin 26. It will create a TreeDataProvider with HierarchicalDataProvider.HierarchyFormat.FLATTENED, which may affect TreeGrid methods whose behavior depends on the hierarchy format, such as scrollToIndex. To preserve the current behavior, create a TreeDataProvider manually with HierarchicalDataProvider.HierarchyFormat.NESTED and set it via setDataProvider(HierarchicalDataProvider) instead of using this shorthand method.

Sets the root data items of this component provided as a stream and recursively populates them with child items with the given value provider.

The provided items are wrapped into a TreeDataProvider backed by a flat TreeData structure. The data provider instance is used as a parameter for the setDataProvider(HierarchicalDataProvider) method. It means that the items collection can be accessed later on via getTreeData():

 
 Stream<Person> grandParents = getGrandParents();
 HasHierarchicalDataProvider<Person> treeGrid = new TreeGrid<>();
 treeGrid.setItems(grandParents, Person::getChildren);
 ...

 TreeData<Person> data = treeGrid.getTreeData();
 
 

The returned TreeData instance may be used as-is to add, remove or modify items in the hierarchy. These modifications to the object are not automatically reflected back to the TreeGrid. Items modified should be refreshed with DataProvider.refreshItem(Object) and when adding or removing items DataProvider.refreshAll() should be called.

Parameters:

rootItems - the root items to display, not null

childItemProvider - the value provider used to recursively populate the given root items with child items, not null

setDataProvider

void setDataProvider(HierarchicalDataProvider<T,?> hierarchicalDataProvider)

Sets the hierarchical data provider for this listing. The data provider provides the items and the hierarchy as needed.

Parameters:

hierarchicalDataProvider - the hierarchical data provider to use, not null

Since:

4.0