GWT 2.3.0

com.google.gwt.view.client
Class ListDataProvider<T>

java.lang.Object
  extended by com.google.gwt.view.client.AbstractDataProvider<T>
      extended by com.google.gwt.view.client.ListDataProvider<T>
Type Parameters:
T - the data type of the list
All Implemented Interfaces:
ProvidesKey<T>

public class ListDataProvider<T>
extends AbstractDataProvider<T>

A concrete subclass of AbstractDataProvider that is backed by an in-memory list.

Example

public class ListDataProviderExample implements EntryPoint {

  public void onModuleLoad() {
    // Create a CellList.
    CellList<String> cellList = new CellList<String>(new TextCell());

    // Create a list data provider.
    final ListDataProvider<String> dataProvider = new ListDataProvider<String>();

    // Add the cellList to the dataProvider.
    dataProvider.addDataDisplay(cellList);

    // Create a form to add values to the data provider.
    final TextBox valueBox = new TextBox();
    valueBox.setText("Enter new value");
    Button addButton = new Button("Add value", new ClickHandler() {
      public void onClick(ClickEvent event) {
        // Get the value from the text box.
        String newValue = valueBox.getText();

        // Get the underlying list from data dataProvider.
        List<String> list = dataProvider.getList();

        // Add the value to the list. The dataProvider will update the cellList.
        list.add(newValue);
      }
    });

    // Add the widgets to the root panel.
    VerticalPanel vPanel = new VerticalPanel();
    vPanel.add(valueBox);
    vPanel.add(addButton);
    vPanel.add(cellList);
    RootPanel.get().add(vPanel);
  }
}


Constructor Summary
ListDataProvider()
          Creates an empty model.
ListDataProvider(java.util.List<T> listToWrap)
          Creates a list model that wraps the given list.
ListDataProvider(java.util.List<T> listToWrap, ProvidesKey<T> keyProvider)
          Creates a list model that wraps the given list.
ListDataProvider(ProvidesKey<T> keyProvider)
          Creates an empty list model that wraps the given collection.
 
Method Summary
 void flush()
          Flush pending list changes to the displays.
 java.util.List<T> getList()
          Get the list that backs this model.
protected  void onRangeChanged(HasData<T> display)
          Called when a display changes its range of interest.
 void refresh()
          Refresh all of the displays listening to this adapter.
 void setList(java.util.List<T> listToWrap)
          Replace this model's list.
 
Methods inherited from class com.google.gwt.view.client.AbstractDataProvider
addDataDisplay, getDataDisplays, getKey, getKeyProvider, getRanges, removeDataDisplay, updateRowCount, updateRowData, updateRowData
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ListDataProvider

public ListDataProvider()
Creates an empty model.


ListDataProvider

public ListDataProvider(java.util.List<T> listToWrap)
Creates a list model that wraps the given list. Changes to the wrapped list must be made via this model in order to be correctly applied to displays.

Parameters:
listToWrap - the List to be wrapped

ListDataProvider

public ListDataProvider(ProvidesKey<T> keyProvider)
Creates an empty list model that wraps the given collection.

Parameters:
keyProvider - an instance of ProvidesKey, or null if the record object should act as its own key

ListDataProvider

public ListDataProvider(java.util.List<T> listToWrap,
                        ProvidesKey<T> keyProvider)
Creates a list model that wraps the given list. Changes to the wrapped list must be made via this model in order to be correctly applied to displays.

Parameters:
listToWrap - the List to be wrapped
keyProvider - an instance of ProvidesKey, or null if the record object should act as its own key
Method Detail

flush

public void flush()
Flush pending list changes to the displays. By default, displays are informed of modifications to the underlying list at the end of the current event loop, which makes it possible to perform multiple operations synchronously without repeatedly refreshing the displays. This method can be called to flush the changes immediately instead of waiting until the end of the current event loop.


getList

public java.util.List<T> getList()
Get the list that backs this model. Changes to the list will be reflected in the model.

Returns:
the list
See Also:
setList(List)

refresh

public void refresh()
Refresh all of the displays listening to this adapter.


setList

public void setList(java.util.List<T> listToWrap)
Replace this model's list.

Parameters:
listToWrap - the model's new list
See Also:
getList()

onRangeChanged

protected void onRangeChanged(HasData<T> display)
Description copied from class: AbstractDataProvider
Called when a display changes its range of interest.

Specified by:
onRangeChanged in class AbstractDataProvider<T>
Parameters:
display - the display whose range has changed

GWT 2.3.0