Class ComboBox<T>

Constructor Detail

• ComboBox

  public ComboBox​(int pageSize)

  Creates an empty combo box with the defined page size for lazy loading.

  The default page size is 50.

  The page size is also the largest number of items that can support client-side filtering. If you provide more items than the page size, the component has to fall back to server-side filtering.

  Parameters:

  pageSize - the amount of items to request at a time for lazy loading

• ComboBox

  public ComboBox()

  Default constructor. Creates an empty combo box.

• ComboBox

  public ComboBox​(String label)

  Creates an empty combo box with the defined label.

  Parameters:

  label - the label describing the combo box

  See Also:

  setLabel(String)

• ComboBox

  public ComboBox​(String label,
                  Collection<T> items)

  Creates a combo box with the defined label and populated with the items in the collection.

  Parameters:

  label - the label describing the combo box

  items - the items to be shown in the list of the combo box

  See Also:

  setLabel(String), setItems(Collection)

• ComboBox

  @SafeVarargs
  public ComboBox​(String label,
                  T... items)

  Creates a combo box with the defined label and populated with the items in the array.

  Parameters:

  label - the label describing the combo box

  items - the items to be shown in the list of the combo box

  See Also:

  setLabel(String), HasListDataView.setItems(Object...)

• ComboBox

  public ComboBox​(HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>> listener)

  Constructs a combo box with a value change listener.

  Parameters:

  listener - the value change listener to add

  See Also:

  AbstractField.addValueChangeListener(ValueChangeListener)

• ComboBox

  public ComboBox​(String label,
                  HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>> listener)

  Constructs a combo box with the defined label and a value change listener.

  Parameters:

  label - the label describing the combo box

  listener - the value change listener to add

  See Also:

  setLabel(String), AbstractField.addValueChangeListener(ValueChangeListener)

• ComboBox

  @SafeVarargs
  public ComboBox​(String label,
                  HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>> listener,
                  T... items)

  Constructs a combo box with the defined label, a value change listener and populated with the items in the array.

  Parameters:

  label - the label describing the combo box

  listener - the value change listener to add

  items - the items to be shown in the list of the combo box

  See Also:

  setLabel(String), AbstractField.addValueChangeListener(ValueChangeListener), HasListDataView.setItems(Object...)

Method Detail

• setValue

  public void setValue​(T value)

  Description copied from interface: HasValue

  Sets the value of this object. If the new value is not equal to getValue(), fires a value change event. May throw IllegalArgumentException if the value is not acceptable.

  Implementation note: the implementing class should document whether null values are accepted or not, and override HasValue.getEmptyValue() if the empty value is not null.

  Specified by:

  setValue in interface HasValue<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>,​T>

  Overrides:

  setValue in class AbstractField<ComboBox<T>,​T>

  Parameters:

  value - the new value

• setRenderer

  public void setRenderer​(Renderer<T> renderer)

  Sets the Renderer responsible to render the individual items in the list of possible choices of the ComboBox. It doesn't affect how the selected item is rendered - that can be configured by using setItemLabelGenerator(ItemLabelGenerator).

  Parameters:

  renderer - a renderer for the items in the selection list of the ComboBox, not null Note that filtering of the ComboBox is not affected by the renderer that is set here. Filtering is done on the original values and can be affected by setItemLabelGenerator(ItemLabelGenerator).

• setItems

  public ComboBoxListDataView<T> setItems​(Collection<T> items)

  Sets the items from the given Collection and returns a ListDataView that provides information and allows operations on the items.

  Filtering will use a case insensitive match to show all items where the filter text is a substring of the label displayed for that item, which you can configure with setItemLabelGenerator(ItemLabelGenerator).

  Filtering will be handled in the client-side if the size of the data set is less than the page size. To force client-side filtering with a larger data set (at the cost of increased network traffic), you can increase the page size with setPageSize(int).

  Setting the items resets the combo box's value to null.

  Specified by:

  setItems in interface HasListDataView<T,​ComboBoxListDataView<T>>

  Parameters:

  items - the items to display, not null

  Returns:

  ListDataView providing access to the items

• setItems

  public ComboBoxListDataView<T> setItems​(ComboBox.ItemFilter<T> itemFilter,
                                          Collection<T> items)

  Sets the data items of this combo box and a filtering function for defining which items are displayed when user types into the combo box.

  Note that defining a custom filter will force the component to make server roundtrips to handle the filtering. Otherwise it can handle filtering in the client-side, if the size of the data set is less than the pageSize.

  Setting the items resets the combo box's value to null.

  The returned data view object can be used for further access to combo box items, or later on fetched with getListDataView(). For using lazy data loading, use one of the setItems methods which take a fetch callback parameter instead.

  Parameters:

  itemFilter - filter to check if an item is shown when user typed some text into the ComboBox

  items - the data items to display

  Returns:

  the in-memory data view instance that provides access to the data bound to the combo box

• setItems

  public ComboBoxListDataView<T> setItems​(ComboBox.ItemFilter<T> itemFilter,
                                          T... items)

  Sets the data items of this combo box and a filtering function for defining which items are displayed when user types into the combo box.

  Note that defining a custom filter will force the component to make server roundtrips to handle the filtering. Otherwise it can handle filtering in the client-side, if the size of the data set is less than the pageSize.

  Setting the items resets the combo box's value to null.

  The returned data view object can be used for further access to combo box items, or later on fetched with getListDataView(). For using lazy data loading, use one of the setItems methods which take a fetch callback parameter instead.

  Parameters:

  itemFilter - filter to check if an item is shown when user typed some text into the ComboBox

  items - the data items to display

  Returns:

  the in-memory data view instance that provides access to the data bound to the combo box

• setItems

  @Deprecated
  public void setItems​(Stream<T> streamOfItems)

  Deprecated.

  Because the stream is collected to a list anyway, use setItems(Collection) or setItems(CallbackDataProvider.FetchCallback) instead.

• setItems

  public ComboBoxDataView<T> setItems​(DataProvider<T,​String> dataProvider)

  Description copied from interface: HasDataView

  Set a generic data provider for the component to use and returns the base DataView that provides API to get information on the items.

  This method should be used only when the data provider type is not either ListDataProvider or BackEndDataProvider.

  Specified by:

  setItems in interface HasDataView<T,​String,​ComboBoxDataView<T>>

  Parameters:

  dataProvider - DataProvider instance to use, not null

  Returns:

  DataView providing information on the data

• setItems

  @Deprecated
  public ComboBoxDataView<T> setItems​(InMemoryDataProvider<T> dataProvider)

  Deprecated.

  does not work so don't use

  The method is not supported for the ComboBox component, use another overloaded method with filter converter setItems(InMemoryDataProvider, SerializableFunction)

  Always throws an UnsupportedOperationException.

  Specified by:

  setItems in interface HasDataView<T,​String,​ComboBoxDataView<T>>

  Parameters:

  dataProvider - InMemoryDataProvider to use, not null

  Returns:

  DataView providing information on the data

  Throws:

  UnsupportedOperationException

  See Also:

  setItems(InMemoryDataProvider, SerializableFunction)

• setItems

  public ComboBoxDataView<T> setItems​(InMemoryDataProvider<T> inMemoryDataProvider,
                                      SerializableFunction<String,​SerializablePredicate<T>> filterConverter)

  Sets an in-memory data provider for the combo box to use, taking into account both in-memory filtering from data provider and combo box's text filter.

  Text filter is transformed into a predicate filter through the given filter converter. Example of filter converter which produces the Person's name predicate: (String nameFilter) -> person -> person.getName().equalsIgnoreCase (nameFilter);

  Filtering will be handled in the client-side if the size of the data set is less than the page size. To force client-side filtering with a larger data set (at the cost of increased network traffic), you can increase the page size with setPageSize(int).

  Note! Using a ListDataProvider instead of a InMemoryDataProvider is recommended to get access to ListDataView API by using setItems(ListDataProvider).

  Parameters:

  inMemoryDataProvider - InMemoryDataProvider to use, not null

  filterConverter - a function which converts a component's internal filter into a predicate applied to the data provider

  Returns:

  DataView providing information on the data

• getGenericDataView

  public ComboBoxDataView<T> getGenericDataView()

  Gets the generic data view for the ComboBox. This data view can be used when getListDataView() or getLazyDataView() are not applicable for the underlying data provider, or you don't want to distinct between which type of data view to use.

  Specified by:

  getGenericDataView in interface HasDataView<T,​String,​ComboBoxDataView<T>>

  Returns:

  the generic DataView implementation for ComboBox

  See Also:

  getListDataView(), getLazyDataView()

• setItems

  public ComboBoxLazyDataView<T> setItems​(BackEndDataProvider<T,​String> dataProvider)

  Description copied from interface: HasLazyDataView

  Supply items with a BackEndDataProvider that lazy loads items from a backend. Note that component will query the data provider for the item count. In case that is not desired for performance reasons, use HasLazyDataView.setItems(CallbackDataProvider.FetchCallback) instead.

  The returned data view object can be used for further configuration, or later on fetched with HasLazyDataView.getLazyDataView(). For using in-memory data, like Collection, use HasListDataView.setItems(Collection) instead.

  Specified by:

  setItems in interface HasLazyDataView<T,​String,​ComboBoxLazyDataView<T>>

  Parameters:

  dataProvider - BackEndDataProvider instance

  Returns:

  LazyDataView instance for further configuration

• getLazyDataView

  public ComboBoxLazyDataView<T> getLazyDataView()

  Gets the lazy data view for the ComboBox. This data view should only be used when the items are provided lazily from the backend with:

  • setItems(CallbackDataProvider.FetchCallback)
  • setItemsWithFilterConverter(CallbackDataProvider.FetchCallback, SerializableFunction)
  • setItems(CallbackDataProvider.FetchCallback, CallbackDataProvider.CountCallback)
  • setItemsWithFilterConverter(CallbackDataProvider.FetchCallback, CallbackDataProvider.CountCallback, SerializableFunction)
  • setItems(BackEndDataProvider)
  If the items are not fetched lazily an exception is thrown. When the items are in-memory, use getListDataView() instead.

  Specified by:

  getLazyDataView in interface HasLazyDataView<T,​String,​ComboBoxLazyDataView<T>>

  Returns:

  the lazy data view that provides access to the data bound to the ComboBox

  Throws:

  IllegalStateException - if no items fetch callback(s) set

• setItems

  public ComboBoxListDataView<T> setItems​(ListDataProvider<T> dataProvider)

  Description copied from interface: HasListDataView

  Sets a ListDataProvider for the component to use and returns a ListDataView that provides information and allows operations on the items.

  Specified by:

  setItems in interface HasListDataView<T,​ComboBoxListDataView<T>>

  Parameters:

  dataProvider - ListDataProvider providing items to the component.

  Returns:

  ListDataView providing access to the items

• getListDataView

  public ComboBoxListDataView<T> getListDataView()

  Gets the list data view for the ComboBox. This data view should only be used when the items are in-memory set with:

  • setItems(Collection)
  • HasListDataView.setItems(Object[])
  • setItems(ListDataProvider)
  • setItems(ItemFilter, ListDataProvider)
  • setItems(ItemFilter, Object[])
  • setItems(ItemFilter, Collection)
  If the items are not in-memory an exception is thrown. When the items are fetched lazily, use getLazyDataView() instead.

  Specified by:

  getListDataView in interface HasListDataView<T,​ComboBoxListDataView<T>>

  Returns:

  the list data view that provides access to the items in the ComboBox

• setDataProvider

  @Deprecated
  public void setDataProvider​(DataProvider<T,​String> dataProvider)

  Deprecated.

  use instead one of the setItems methods which provide access to either ComboBoxListDataView or ComboBoxLazyDataView

  The filter-type of the given data provider must be String so that it can handle the filters typed into the ComboBox by users. If your data provider uses some other type of filter, you can provide a function which converts the ComboBox's filter-string into that type via setDataProvider(DataProvider, SerializableFunction). Another way to do the same thing is to use this method with your data provider converted with DataProvider.withConvertedFilter(SerializableFunction).

  Changing the combo box's data provider resets its current value to null.

• setItemsWithFilterConverter

  public <C> ComboBoxLazyDataView<T> setItemsWithFilterConverter​(CallbackDataProvider.FetchCallback<T,​C> fetchCallback,
                                                                 SerializableFunction<String,​C> filterConverter)

  Supply items lazily with a callback from a backend, using custom filter type. The combo box will automatically fetch more items and adjust its size until the backend runs out of items. Usage example:

  comboBox.setItemsWithFilterConverter( query -> orderService.getOrdersByCount(query.getFilter(), query.getOffset, query.getLimit()), orderCountStr -> Integer.parseInt(orderCountStr)); Note: Validations for orderCountStr are omitted for briefness.

  Combo box's client-side filter typed by the user is transformed into a callback's filter through the given filter converter.

  The returned data view object can be used for further configuration, or later on fetched with getLazyDataView(). For using in-memory data, like Collection, use setItems(Collection) instead.

  Type Parameters:

  C - filter type used by a callback

  Parameters:

  fetchCallback - function that returns a stream of items from the backend based on the offset, limit and a object filter

  filterConverter - a function which converts a combo box's filter-string typed by the user into a callback's object filter

  Returns:

  ComboBoxLazyDataView instance for further configuration

• setItemsWithFilterConverter

  public <C> ComboBoxLazyDataView<T> setItemsWithFilterConverter​(CallbackDataProvider.FetchCallback<T,​C> fetchCallback,
                                                                 CallbackDataProvider.CountCallback<T,​C> countCallback,
                                                                 SerializableFunction<String,​C> filterConverter)

  Supply items lazily with callbacks: the first one fetches the items based on offset, limit and an optional filter, the second provides the exact count of items in the backend. Use this only in case getting the count is cheap and the user benefits from the component showing immediately the exact size. Usage example:

  comboBox.setItemsWithFilterConverter( query -> orderService.getOrdersByCount(query.getFilter(), query.getOffset, query.getLimit()), query -> orderService.getSize(query.getFilter()), orderCountStr -> Integer.parseInt(orderCountStr)); Note: Validations for orderCountStr are omitted for briefness.

  Combo box's client-side filter typed by the user is transformed into a custom filter type through the given filter converter.

  The returned data view object can be used for further configuration, or later on fetched with getLazyDataView(). For using in-memory data, like Collection, use setItems(Collection) instead.

  Type Parameters:

  C - filter type used by a callbacks

  Parameters:

  fetchCallback - function that returns a stream of items from the backend based on the offset, limit and a object filter

  filterConverter - a function which converts a combo box's filter-string typed by the user into a callback's object filter

  Returns:

  ComboBoxLazyDataView instance for further configuration

• setDataProvider

  @Deprecated
  public <C> void setDataProvider​(DataProvider<T,​C> dataProvider,
                                  SerializableFunction<String,​C> filterConverter)

  Deprecated.

  use instead one of the setItems methods which provide access to either ComboBoxListDataView or ComboBoxLazyDataView

  ComboBox triggers filtering queries based on the strings users type into the field. For this reason you need to provide the second parameter, a function which converts the filter-string typed by the user into filter-type used by your data provider. If your data provider already supports String as the filter-type, it can be used without a converter function via setDataProvider(DataProvider).

  Using this method provides the same result as using a data provider wrapped with DataProvider.withConvertedFilter(SerializableFunction).

  Changing the combo box's data provider resets its current value to null.

• onAttach

  protected void onAttach​(AttachEvent attachEvent)

  Description copied from class: Component

  Called when the component is attached to a UI.

  The default implementation does nothing.

  This method is invoked before the AttachEvent is fired for the component.

  Overrides:

  onAttach in class Component

  Parameters:

  attachEvent - the attach event

• onDetach

  protected void onDetach​(DetachEvent detachEvent)

  Description copied from class: Component

  Called when the component is detached from a UI.

  The default implementation does nothing.

  This method is invoked before the DetachEvent is fired for the component.

  Overrides:

  onDetach in class Component

  Parameters:

  detachEvent - the detach event

• setDataProvider

  @Deprecated
  public void setDataProvider​(ListDataProvider<T> listDataProvider)

  Deprecated.

  use instead one of the setItems methods which provide access to ComboBoxListDataView

  Sets a list data provider as the data provider of this combo box.

  Filtering will use a case insensitive match to show all items where the filter text is a substring of the label displayed for that item, which you can configure with setItemLabelGenerator(ItemLabelGenerator).

  Filtering will be handled in the client-side if the size of the data set is less than the page size. To force client-side filtering with a larger data set (at the cost of increased network traffic), you can increase the page size with setPageSize(int).

  Changing the combo box's data provider resets its current value to null.

  Parameters:

  listDataProvider - the list data provider to use, not null

• setDataProvider

  @Deprecated
  public void setDataProvider​(ComboBox.FetchItemsCallback<T> fetchItems,
                              SerializableFunction<String,​Integer> sizeCallback)

  Deprecated.

  use instead setItems(CallbackDataProvider.FetchCallback, CallbackDataProvider.CountCallback) which provide access to ComboBoxLazyDataView

  Sets a CallbackDataProvider using the given fetch items callback and a size callback.

  This method is a shorthand for making a CallbackDataProvider that handles a partial Query object.

  Changing the combo box's data provider resets its current value to null.

  Parameters:

  fetchItems - a callback for fetching items, not null

  sizeCallback - a callback for getting the count of items, not null

  See Also:

  CallbackDataProvider, setDataProvider(DataProvider)

• setDataProvider

  @Deprecated
  public void setDataProvider​(ComboBox.ItemFilter<T> itemFilter,
                              ListDataProvider<T> listDataProvider)

  Deprecated.

  use instead setItems(ItemFilter, ListDataProvider) which provide access to ComboBoxListDataView

  Sets a list data provider with an item filter as the data provider of this combo box. The item filter is used to compare each item to the filter text entered by the user.

  Note that defining a custom filter will force the component to make server roundtrips to handle the filtering. Otherwise it can handle filtering in the client-side, if the size of the data set is less than the pageSize.

  Changing the combo box's data provider resets its current value to null.

  Parameters:

  itemFilter - filter to check if an item is shown when user typed some text into the ComboBox

  listDataProvider - the list data provider to use, not null

• setItems

  public ComboBoxListDataView<T> setItems​(ComboBox.ItemFilter<T> itemFilter,
                                          ListDataProvider<T> listDataProvider)

  Sets a ListDataProvider for this combo box and a filtering function for defining which items are displayed when user types into the combo box.

  Note that defining a custom filter will force the component to make server roundtrips to handle the filtering. Otherwise it can handle filtering in the client-side, if the size of the data set is less than the pageSize.

  Setting the items resets the combo box's value to null.

  The returned data view object can be used for further access to combo box items, or later on fetched with getListDataView(). For using lazy data loading, use one of the setItems methods which take a fetch callback parameter instead.

  Parameters:

  itemFilter - filter to check if an item is shown when user typed some text into the ComboBox.

  listDataProvider - ListDataProvider providing items to the component.

  Returns:

  the in-memory data view instance that provides access to the data bound to the combo box

• getDataProvider

  public DataProvider<T,​?> getDataProvider()

  Gets the data provider used by this ComboBox.

  Returns:

  the data provider used by this ComboBox

• setItemLabelGenerator

  public void setItemLabelGenerator​(ItemLabelGenerator<T> itemLabelGenerator)

  Sets the item label generator that is used to produce the strings shown in the combo box for each item. By default, String.valueOf(Object) is used.

  When the setRenderer(Renderer) is used, the ItemLabelGenerator is only used to show the selected item label.

  Parameters:

  itemLabelGenerator - the item label provider to use, not null

• getItemLabelGenerator

  public ItemLabelGenerator<T> getItemLabelGenerator()

  Gets the item label generator that is used to produce the strings shown in the combo box for each item.

  Returns:

  the item label generator used, not null

• setPageSize

  public void setPageSize​(int pageSize)

  Sets the page size, which is the number of items requested at a time from the data provider. This does not guarantee a maximum query size to the backend; when the overlay has room to render more new items than the page size, multiple "pages" will be requested at once.

  The page size is also the largest number of items that can support client-side filtering. If you provide more items than the page size, the component has to fall back to server-side filtering.

  Setting the page size after the ComboBox has been rendered effectively resets the component, and the current page(s) and sent over again.

  The default page size is 50.

  Parameters:

  pageSize - the maximum number of items sent per request, should be greater than zero

• getPageSize

  public int getPageSize()

  Gets the page size, which is the number of items fetched at a time from the data provider.

  The page size is also the largest number of items that can support client-side filtering. If you provide more items than the page size, the component has to fall back to server-side filtering.

  The default page size is 50.

  Returns:

  the maximum number of items sent per request

• setOpened

  public void setOpened​(boolean opened)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  True if the dropdown is open, false otherwise.

  Overrides:

  setOpened in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  opened - the boolean value to set

• isOpened

  public boolean isOpened()

  Gets the states of the drop-down.

  Returns:

  true if the drop-down is opened, false otherwise

• setInvalid

  public void setInvalid​(boolean invalid)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  Set to true if the value is invalid.

  Specified by:

  setInvalid in interface HasValidation

  Overrides:

  setInvalid in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  invalid - the boolean value to set

• isInvalid

  public boolean isInvalid()

  Gets the validity of the combobox output.

  return true, if the value is invalid.

  Specified by:

  isInvalid in interface HasValidation

  Returns:

  the validity property from the component

• setErrorMessage

  public void setErrorMessage​(String errorMessage)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  The error message to display when the input is invalid.

  Specified by:

  setErrorMessage in interface HasValidation

  Overrides:

  setErrorMessage in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  errorMessage - the String value to set

• getErrorMessage

  public String getErrorMessage()

  Gets the current error message from the combobox.

  Specified by:

  getErrorMessage in interface HasValidation

  Returns:

  the current error message

• setAllowCustomValue

  public void setAllowCustomValue​(boolean allowCustomValue)

  Enables or disables the component firing events for custom string input.

  When enabled, a GeneratedVaadinComboBox.CustomValueSetEvent will be fired when the user inputs a string value that does not match any existing items and commits it eg. by blurring or pressing the enter-key.

  Note that ComboBox doesn't do anything with the custom value string automatically. Use the addCustomValueSetListener(ComponentEventListener) method to determine how the custom value should be handled. For example, when the ComboBox has String as the value type, you can add a listener which sets the custom string as the value of the ComboBox with setValue(Object).

  Setting to true also allows an unfocused ComboBox to display a string that doesn't match any of its items nor its current value, unless this is explicitly handled with addCustomValueSetListener(ComponentEventListener). When set to false, an unfocused ComboBox will always display the label of the currently selected item.

  Overrides:

  setAllowCustomValue in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  allowCustomValue - true to enable custom value set events, false to disable them

  See Also:

  addCustomValueSetListener(ComponentEventListener)

• isAllowCustomValue

  public boolean isAllowCustomValue()

  If true, the user can input string values that do not match to any existing item labels, which will fire a GeneratedVaadinComboBox.CustomValueSetEvent.

  Returns:

  true if the component fires custom value set events, false otherwise

  See Also:

  setAllowCustomValue(boolean), addCustomValueSetListener(ComponentEventListener)

• setAutoOpen

  public void setAutoOpen​(boolean autoOpen)

  Enables or disables the dropdown opening automatically. If false the dropdown is only opened when clicking the toggle button or pressing Up or Down arrow keys.

  Parameters:

  autoOpen - false to prevent the dropdown from opening automatically

• isAutoOpen

  public boolean isAutoOpen()

  Gets whether dropdown will open automatically or not.

  Returns:

• setAutofocus

  public void setAutofocus​(boolean autofocus)

  Set the combobox to be input focused when the page loads.

  Overrides:

  setAutofocus in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  autofocus - the boolean value to set

• isAutofocus

  public boolean isAutofocus()

  Get the state for the auto-focus property of the combobox.

  This property is not synchronized automatically from the client side, so the returned value may not be the same as in client side.

  Returns:

  the autofocus property from the combobox

• setPreventInvalidInput

  public void setPreventInvalidInput​(boolean preventInvalidInput)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  Set to true to prevent the user from entering invalid input.

  Overrides:

  setPreventInvalidInput in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  preventInvalidInput - the boolean value to set

• isPreventInvalidInput

  public boolean isPreventInvalidInput()

  Determines whether preventing the user from inputing invalid value.

  This property is not synchronized automatically from the client side, so the returned value may not be the same as in client side.

  Returns:

  the preventInvalidInput property of the combobox

• setRequired

  public void setRequired​(boolean required)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  Set to true to mark the input as required.

  Overrides:

  setRequired in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  required - the boolean value to set

• isRequired

  public boolean isRequired()

  Determines whether the combobox is marked as input required.

  This property is not synchronized automatically from the client side, so the returned value may not be the same as in client side.

  Returns:

  true if the input is required, false otherwise

• setLabel

  public void setLabel​(String label)

  Sets the label for the combobox.

  Specified by:

  setLabel in interface HasLabel

  Overrides:

  setLabel in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  label - value for the label property in the combobox

• getLabel

  public String getLabel()

  Gets the label of the combobox.

  Specified by:

  getLabel in interface HasLabel

  Returns:

  the label property of the combobox

• setPlaceholder

  public void setPlaceholder​(String placeholder)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  A placeholder string in addition to the label.

  Overrides:

  setPlaceholder in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  placeholder - the String value to set

• getPlaceholder

  public String getPlaceholder()

  Gets the placeholder of the combobox.

  Returns:

  the placeholder property of the combobox

• setPattern

  public void setPattern​(String pattern)

  Description copied from class: GeneratedVaadinComboBox

  Description copied from corresponding location in WebComponent:

  A pattern to validate the input with.

  Overrides:

  setPattern in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  pattern - the String value to set

• getPattern

  public String getPattern()

  Gets the valid input pattern

  Returns:

  the pattern property of the combobox

• getEmptyValue

  public T getEmptyValue()

  Description copied from interface: HasValue

  Returns the value that represents an empty value.

  By default HasValue is expected to support null as empty values. Specific implementations might not support this.

  Specified by:

  getEmptyValue in interface HasValue<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>,​T>

  Overrides:

  getEmptyValue in class AbstractField<ComboBox<T>,​T>

  Returns:

  empty value

• addCustomValueSetListener

  public Registration addCustomValueSetListener​(ComponentEventListener<GeneratedVaadinComboBox.CustomValueSetEvent<ComboBox<T>>> listener)

  Adds a listener for the event which is fired when user inputs a string value that does not match any existing items and commits it eg. by blurring or pressing the enter-key.

  Note that ComboBox doesn't do anything with the custom value string automatically. Use this method to determine how the custom value should be handled. For example, when the ComboBox has String as the value type, you can add a listener which sets the custom string as the value of the ComboBox with setValue(Object).

  As a side effect, this makes the ComboBox allow custom values. If you want to disable the firing of custom value set events once the listener is added, please disable it explicitly via the setAllowCustomValue(boolean) method.

  The custom value becomes disallowed automatically once the last custom value set listener is removed.

  Overrides:

  addCustomValueSetListener in class GeneratedVaadinComboBox<ComboBox<T>,​T>

  Parameters:

  listener - the listener to be notified when a new value is filled

  Returns:

  a Registration for removing the event listener

  See Also:

  setAllowCustomValue(boolean)

• setRequiredIndicatorVisible

  public void setRequiredIndicatorVisible​(boolean requiredIndicatorVisible)

  Description copied from interface: HasValue

  Sets the required indicator visible or not.

  If set visible, it is visually indicated in the user interface.

  The method is intended to be used with Binder which does server-side validation. In case HTML element has its own (client-side) validation it should be disabled when setRequiredIndicatorVisible(true) is called and re-enabled back on setRequiredIndicatorVisible(false). It's responsibility of each component implementation to follow the contract so that the method call doesn't do anything else than show/hide the "required" indication. Usually components provide their own setRequired method which should be called in case the client-side validation is required.

  Specified by:

  setRequiredIndicatorVisible in interface HasValue<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>,​T>

  Specified by:

  setRequiredIndicatorVisible in interface HasValueAndElement<AbstractField.ComponentValueChangeEvent<ComboBox<T>,​T>,​T>

  Parameters:

  requiredIndicatorVisible - true to make the required indicator visible, false if not

• setItems

  public ComboBoxLazyDataView<T> setItems​(CallbackDataProvider.FetchCallback<T,​String> fetchCallback)

  Supply items lazily with a callback from a backend. The ComboBox will automatically fetch more items and adjust its size until the backend runs out of items. Usage example without component provided filter:

  comboBox.setItems(query -> orderService.getOrders(query.getOffset(), query.getLimit());

  Since ComboBox supports filtering, it can be fetched via query.getFilter():

  comboBox.setItems(query -> orderService.getOrders(query.getFilter(), query.getOffset(), query.getLimit());

  The returned data view object can be used for further configuration, or later on fetched with getLazyDataView(). For using in-memory data, like Collection, use HasListDataView.setItems(Collection) instead.

  If item filtering by some value type other than String is preferred and backend service is able to fetch and filter items by such type, converter for client side's filter string can be set along with fetch callback. See: setItemsWithFilterConverter(CallbackDataProvider.FetchCallback, SerializableFunction)

  Specified by:

  setItems in interface HasLazyDataView<T,​String,​ComboBoxLazyDataView<T>>

  Parameters:

  fetchCallback - function that returns a stream of items from the backend based on the offset, limit and an optional filter provided by the query object

  Returns:

  ComboBoxLazyDataView instance for further configuration

• setItems

  public ComboBoxLazyDataView<T> setItems​(CallbackDataProvider.FetchCallback<T,​String> fetchCallback,
                                          CallbackDataProvider.CountCallback<T,​String> countCallback)

  Supply items lazily with callbacks: the first one fetches the items based on offset, limit and an optional filter, the second provides the exact count of items in the backend. Use this only in case getting the count is cheap and the user benefits from the ComboBox showing immediately the exact size. Usage example without component provided filter:

  comboBox.setItems( query -> orderService.getOrders(query.getOffset, query.getLimit()), query -> orderService.getSize());

  Since ComboBox supports filtering, it can be fetched via query.getFilter():

  comboBox.setItems( query -> orderService.getOrders(query.getFilter(), query.getOffset, query.getLimit()), query -> orderService.getSize(query.getFilter()));

  The returned data view object can be used for further configuration, or later on fetched with getLazyDataView(). For using in-memory data, like Collection, use HasListDataView.setItems(Collection) instead.

  If item filtering by some value type other than String is preferred and backend service is able to fetch and filter items by such type, converter for client side's filter string can be set along with fetch callback. See: setItemsWithFilterConverter(CallbackDataProvider.FetchCallback, CallbackDataProvider.CountCallback, SerializableFunction)

  Specified by:

  setItems in interface HasLazyDataView<T,​String,​ComboBoxLazyDataView<T>>

  Parameters:

  fetchCallback - function that returns a stream of items from the back end for a query

  countCallback - function that return the number of items in the back end for a query

  Returns:

  ComboBoxLazyDataView instance for further configuration

• addThemeVariants

  public void addThemeVariants​(ComboBoxVariant... variants)

  Adds theme variants to the component.

  Parameters:

  variants - theme variants to add

• removeThemeVariants

  public void removeThemeVariants​(ComboBoxVariant... variants)

  Removes theme variants from the component.

  Parameters:

  variants - theme variants to remove