Class SplitLayoutPanel

All Implemented Interfaces:
HasAttachHandlers, HasHandlers, EventListener, AnimatedLayout, HasVisibility, HasWidgets, HasWidgets.ForIsWidget, IndexedPanel, IndexedPanel.ForIsWidget, IsWidget, ProvidesResize, RequiresResize, Iterable<Widget>

public class SplitLayoutPanel extends DockLayoutPanel
A panel that adds user-positioned splitters between each of its child widgets.

This panel is used in the same way as DockLayoutPanel, except that its children's sizes are always specified in Style.Unit.PX units, and each pair of child widgets has a splitter between them that the user can drag.

This widget will only work in standards mode, which requires that the HTML page in which it is run have an explicit <!DOCTYPE> declaration.

CSS Style Rules

  • .gwt-SplitLayoutPanel { the panel itself }
  • .gwt-SplitLayoutPanel .gwt-SplitLayoutPanel-HDragger { horizontal dragger }
  • .gwt-SplitLayoutPanel .gwt-SplitLayoutPanel-VDragger { vertical dragger }


public class SplitLayoutPanelExample implements EntryPoint {

  public void onModuleLoad() {
    // Create a three-pane layout with splitters. 
    SplitLayoutPanel p = new SplitLayoutPanel();
    p.addWest(new HTML("navigation"), 128);
    p.addNorth(new HTML("list"), 384);
    p.add(new HTML("details"));

    // Attach the LayoutPanel to the RootLayoutPanel. The latter will listen for
    // resize events on the window to ensure that its children are informed of
    // possible size changes.
    RootLayoutPanel rp = RootLayoutPanel.get();

  • Constructor Details

    • SplitLayoutPanel

      public SplitLayoutPanel()
      Construct a new SplitLayoutPanel with the default splitter size of 8px.
    • SplitLayoutPanel

      public SplitLayoutPanel(int splitterSize)
      Construct a new SplitLayoutPanel with the specified splitter size in pixels.
      splitterSize - the size of the splitter in pixels
  • Method Details

    • getSplitterSize

      public int getSplitterSize()
      Return the size of the splitter in pixels.
      the splitter size
    • insert

      public void insert(Widget child, DockLayoutPanel.Direction direction, double size, Widget before)
      Description copied from class: DockLayoutPanel
      Adds a widget to the specified edge of the dock. If the widget is already a child of this panel, this method behaves as though DockLayoutPanel.remove(Widget) had already been called.
      insert in class DockLayoutPanel
      child - the widget to be added
      direction - the widget's direction in the dock
      before - the widget before which to insert the new child, or null to append
    • remove

      public boolean remove(Widget child)
      Description copied from class: Panel
      Removes a child widget.

      How to Override this Method

      There are several important things that must take place in the correct order to properly remove a Widget from a Panel. Not all of these steps will be relevant to every Panel, but all of the steps must be considered.

      1. Validate: Make sure this Panel is actually the parent of the child Widget; return false if it is not.
      2. Orphan: Call Panel.orphan(Widget) first while the child Widget is still attached.
      3. Physical Detach: Adjust the DOM to account for the removal of the child Widget. The Widget's Element must be physically removed from the DOM.
      4. Logical Detach: Update the Panel's state variables to reflect the removal of the child Widget. Example: the Widget is removed from the Panel's WidgetCollection.

      Specified by:
      remove in interface HasWidgets
      remove in class DockLayoutPanel
      child - the widget to be removed
      true if the child was present
    • setWidgetHidden

      public void setWidgetHidden(Widget widget, boolean hidden)
      Description copied from class: DockLayoutPanel
      Sets whether or not the given widget should be hidden.
      setWidgetHidden in class DockLayoutPanel
      widget - the widget to hide or display
      hidden - true to hide the widget, false to display it
    • setWidgetMinSize

      public void setWidgetMinSize(Widget child, int minSize)
      Sets the minimum allowable size for the given widget.

      Its associated splitter cannot be dragged to a position that would make it smaller than this size. This method has no effect for the DockLayoutPanel.Direction.CENTER widget.

      child - the child whose minimum size will be set
      minSize - the minimum size for this widget
    • setWidgetSnapClosedSize

      public void setWidgetSnapClosedSize(Widget child, int snapClosedSize)
      Sets a size below which the slider will close completely. This can be used in conjunction with setWidgetMinSize(, int) to provide a speed-bump effect where the slider will stick to a preferred minimum size before closing completely.

      This method has no effect for the DockLayoutPanel.Direction.CENTER widget.

      child - the child whose slider should snap closed
      snapClosedSize - the width below which the widget will close or -1 to disable.
    • setWidgetToggleDisplayAllowed

      public void setWidgetToggleDisplayAllowed(Widget child, boolean allowed)
      Sets whether or not double-clicking on the splitter should toggle the display of the widget.
      child - the child whose display toggling will be allowed or not.
      allowed - whether or not display toggling is allowed for this widget