GWT RootLayoutPanel

GWT RootLayoutPanel allows us to choose the starting point of layout panel. In this panel, RequiresResize.onResize() method gets called at a time of creation or whenever the window is resized.

GWT RootLayoutPanel Class Declaration

Let's see the declaration of com.google.gwt.user.client.ui.RootLayoutPanel

GWT RootLayoutPanel Methods

Modifier and Types	Method	Description
static RootLayoutPanel	get()	It gets the singleton instance of RootLayoutPanel.
protected void	onLoad()	It is called immediately after a widget becomes attached to the browser's document.

GWT RootLayoutPanel Example

import com.google.gwt.event.logical.shared.ResizeEvent;
import com.google.gwt.event.logical.shared.ResizeHandler;
import com.google.gwt.user.client.Window;

/* This is the entry point method. */ 

public void onModuleLoad() {

// Attach two child widgets to a LayoutPanel, laying them out horizontally, splitting at 50%. Widget 

childOne = new HTML("left");
Widget childTwo = new HTML("right");
LayoutPanel p = new LayoutPanel();
p.add(childOne);
p.add(childTwo);
p.setWidgetLeftWidth(childOne, 0, Unit.PCT, 50, Unit.PCT);
p.setWidgetRightWidth(childTwo, 0, Unit.PCT, 50, Unit.PCT);

// Attach the LayoutPanel to the RootLayoutPanel
RootLayoutPanel.get().add(p);
 }

Output: