GWT ScrollPanel get max size of children without scrolling - gwt

Question

I was wondering is there any possibility to get the inner size of a
com.google.gwt.user.client.ui.ScrollPanel
object in GWT? I would like to create a children of the ScrollPanel that fits exactly into the empty space, without activating the scroll bars.
The ScrollPanel is initialized as follows:
[begin update after answer of #Abhijith Nagaraja]
public void onModuleLoad() {
Window.setMargin("0px");
TabLayoutPanel tabs = new TabLayoutPanel(30, Unit.PX);
//attach the tab panel to the body element
RootPanel.get(null).add(tabs);
//set the TabLayoutPanel to full size of the window.
String width = (Window.getClientWidth()) + "px";
String height = (Window.getClientHeight()) + "px";
tabs.setSize(width, height);
//create the scroll panel and activate the scroll bars
ScrollPanel scrollPanel = new ScrollPanel(new Button("a second button"));
scrollPanel.getElement().getStyle().setOverflowX(Overflow.SCROLL);
scrollPanel.getElement().getStyle().setOverflowY(Overflow.SCROLL);
//attach the scroll panel to the DOM
tabs.add(scrollPanel, "tab1");
System.out.println(scrollPanel.getOffsetWidth()); // --> 0
System.out.println(scrollPanel.getOffsetHeight()); // --> 0
}
[end update]
Reason: I want to initialize a dynamic visualization (which requires scrollbars at a later point in time) in such a way that, it looks nice and avoiding to add the ScrollPanel later.

Answer 1

ScrollPanel sp = new ScrollPanel();
...
int innerWidth = sp.getOffsetWidth()- sp.getElement().getScrollWidth();
...
NOTE: You can use the above code only if your scrollPanell is attached to the screen. In other words it should be rendered.

Answer 2

DOM.setStyleAttribute(scrollpanel.getElement(), "maxHeight", mMainHeight + "px");;