com.vaadin.client.renderers

Class ImageRenderer

java.lang.Object

com.vaadin.client.renderers.ComplexRenderer<T>

com.vaadin.client.renderers.WidgetRenderer<T,W>

com.vaadin.client.renderers.ClickableRenderer<String,com.google.gwt.user.client.ui.Image>

com.vaadin.client.renderers.ImageRenderer

All Implemented Interfaces:

com.google.gwt.event.dom.client.ClickHandler, com.google.gwt.event.shared.EventHandler, Renderer<String>

public class ImageRenderer
extends ClickableRenderer<String,com.google.gwt.user.client.ui.Image>

A renderer that renders an image into a cell. Click handlers can be added to the renderer, invoked every time any of the images rendered by that rendered is clicked.

Since:

7.4

Author:

Vaadin Ltd

Nested Class Summary

Nested classes/interfaces inherited from class com.vaadin.client.renderers.ClickableRenderer

ClickableRenderer.RendererClickEvent<R>, ClickableRenderer.RendererClickHandler<R>

Field Summary

Fields

Modifier and Type	Field and Description
static String	TRANSPARENT_GIF_1PX Placeholder URL for the image.

Constructor Summary

Constructors

Constructor and Description
ImageRenderer()

Method Summary

Modifier and Type	Method and Description
com.google.gwt.user.client.ui.Image	createWidget() Creates a widget to attach to a cell.
void	render(RendererCellReference cell, String url, com.google.gwt.user.client.ui.Image image) Renders a cell with a widget.

Methods inherited from class com.vaadin.client.renderers.ClickableRenderer

addClickHandler, onClick

Methods inherited from class com.vaadin.client.renderers.WidgetRenderer

getWidget, getWidget, init, render

Methods inherited from class com.vaadin.client.renderers.ComplexRenderer

destroy, destroy, getConsumedEvents, onActivate, onBrowserEvent, setContentVisible

Methods inherited from class java.lang.Object

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

Field Detail

TRANSPARENT_GIF_1PX

public static final String TRANSPARENT_GIF_1PX

Placeholder URL for the image. Used if URL data is set to null.

See Also:

Constant Field Values

Constructor Detail

ImageRenderer

public ImageRenderer()

Method Detail

createWidget

public com.google.gwt.user.client.ui.Image createWidget()

Description copied from class: ClickableRenderer

Creates a widget to attach to a cell. The widgets will be attached to the cell after the cell element has been attached to DOM.

Implementation note: It is the implementing method's responsibility to add this as a click handler of the returned widget, or a widget nested therein, in order to make click events propagate properly to handlers registered via addClickHandler.

Specified by:

createWidget in class ClickableRenderer<String,com.google.gwt.user.client.ui.Image>

Returns:

widget to attach to a cell. All returned instances should be new widget instances without a parent.

render

public void render(RendererCellReference cell,
                   String url,
                   com.google.gwt.user.client.ui.Image image)

Description copied from class: WidgetRenderer

Renders a cell with a widget. This provides a way to update any information in the widget that is cell specific. Do not detach the Widget here, it will be done automatically by the Grid when the widget is no longer needed.

For optimal performance, work done in this method should be kept to a minimum since it will be called continuously while the user is scrolling. The renderer can use Widget.setLayoutData(Object) to store cell data that might be needed in e.g. event listeners.

Specified by:

render in class WidgetRenderer<String,com.google.gwt.user.client.ui.Image>

Parameters:

cell - The cell to render. Note that the cell is a flyweight and should not be stored and used outside of this method as its contents will change.

url - the data of the cell

image - the widget embedded in the cell