question on GWT and dockpanel , sizing and resizing

question on dock panels within gwt

So i want the dockpanel to take up the whole size of the browser window

        dockPanel.setSize("100%", "100%");

if this correct

Next Question, i am going to add a north panel , that will be 100px high and take up the whole width of the browser

    topPanel.setSize("100%", "100px");
    dockPanel.add(topPanel, DockPanel.NORTH);

is this correct, then i want to add a west panel that is 200px wide and the whole length of the browser up to just under the north panel westSideStackPanel.setSize("200px","100%") mainPanel开发者_运维技巧.add(westSideStackPanel,DockPanel.WEST);

i have created all this but when i look at my dockpanel there is a big gap between the west panel and the north panel the whole way accross the screen. why would this be?

The north panel stays at 100px, and then there is a gap of about 100px high the whole width of the screen.

Try using RootLayoutPanel as the base panel (this resizes to the browser window) then use a DockLayoutPanel (v similar to a DockPanel). This approach is documented here.

public void onModuleLoad() {
    RootLayoutPanel rp = RootLayoutPanel.get();
    DockLayoutPanel dp = new DockLayoutPanel(Unit.PX);
    rp.add(dp);
    ...
}

I have experienced some kind of similar problem with DockLayoutPanel in the past and my solution for you would be : switch to LayoutPanel. LayoutPanel can do everything a DockLayoutPanel can do but gives you way more flexibility. In the end, you'll only win out of using LayoutPanel.

Have you tried

dockPanel.setCellHeight(topPanel, "100px");
dockPanel.setCellHeight(westSideStackPanel, "100%");

I don't have much experience with the old DockPanel, but I assume, this could work, because it should set the height of the cells - as opposed to the height of the widgets inside the cells.

In any case, it's probably a good idea to use Firebug to find out exactly, where the gap comes from!