--- a/flys-client/src/main/java/de/intevation/flys/client/client/ui/GaugePanel.java	Thu Oct 25 14:01:46 2012 +0200
+++ b/flys-client/src/main/java/de/intevation/flys/client/client/ui/GaugePanel.java	Thu Oct 25 14:02:39 2012 +0200
@@ -9,6 +9,7 @@
 
 import com.smartgwt.client.types.Overflow;
 import com.smartgwt.client.widgets.Canvas;
+import com.smartgwt.client.widgets.WidgetCanvas;
 import com.smartgwt.client.widgets.events.ResizedEvent;
 import com.smartgwt.client.widgets.events.ResizedHandler;
 import com.smartgwt.client.widgets.layout.SectionStackSection;
@@ -47,6 +48,10 @@
 
     protected RiverInfoPanel riverinfopanel;
 
+    public final static String SECTION_ID = "GaugePanelSection";
+    private final static String GAUGE_TREE_CANVAS_ID =
+        "GaugeTreeCanvas";
+
     /**
      * Creates a new VLayout with a SectionStackSection
      * The GaugePanel's SectionStackSection is hidden by default.
@@ -54,16 +59,24 @@
      * @param flys The FLYS object
      * @param section The section stack section to place the VLayout in.
      */
-    public GaugePanel(FLYS flys, SectionStackSection section) {
+    public GaugePanel(FLYS flys) {
+        SectionStackSection section = new SectionStackSection();
+        section.setExpanded(false);
+        section.setTitle(MSG.gaugePanelTitle());
+        section.setName(SECTION_ID);
+        section.setID(SECTION_ID);
+
         gaugetree = new GaugeTree(flys);
-        gaugetreecanvas = new Canvas();
-        gaugetreecanvas.addChild(gaugetree);
+        gaugetreecanvas = new WidgetCanvas(gaugetree);
+        gaugetreecanvas.setID(GAUGE_TREE_CANVAS_ID);
 
         setOverflow(Overflow.HIDDEN);
+        setStyleName("gaugepanel");
+
         section.setHidden(true);
         section.setItems(this);
         this.section = section;
-        setStyleName("gaugepanel");
+
         addResizedHandler(this);
     }
 
@@ -88,6 +101,8 @@
      * Loads the river info and renders it afterwards
      */
     public void refresh() {
+        contract();
+
         riverInfoService.getGauges(this.river, new AsyncCallback<RiverInfo>() {
             @Override
             public void onFailure(Throwable e) {
@@ -98,6 +113,7 @@
             public void onSuccess(RiverInfo riverinfo) {
                 GWT.log("Loaded river info");
                 renderGaugeOverviewInfo(riverinfo);
+                expand();
             }
         });
     }
@@ -106,11 +122,10 @@
         gaugetree.setGauges(riverinfo);
 
         if (riverinfopanel == null) {
-            removeMembers(getMembers());
+            removeAllMembers();
+
             riverinfopanel = new RiverInfoPanel(riverinfo);
 
-            gaugetreecanvas.setWidth("100%");
-
             addMember(riverinfopanel);
             addMember(gaugetreecanvas);
         }
@@ -135,10 +150,6 @@
 
         gaugetree.setHeight("" + height + "px");
         gaugetree.setWidth("" + width + "px");
-
-        for (Canvas canvas : getMembers()) {
-            GWT.log("GaugePanel - member height " + canvas.getHeight());
-        }
     }
 
 
@@ -163,12 +174,34 @@
     @Override
     public void addMember(Canvas component) {
         super.addMember(component);
-        section.setExpanded(true);
+        expand();
     }
 
     @Override
     public void removeMembers(Canvas[] components) {
         super.removeMembers(components);
+        contract();
+    }
+
+    public SectionStackSection getSection() {
+        return this.section;
+    }
+
+    private void removeAllMembers() {
+        removeMembers(getMembers());
+    }
+
+    /**
+     * Expands the gauge section
+     */
+    public void expand() {
+        section.setExpanded(true);
+    }
+
+    /**
+     * Contracts/shrinks the expanded gauge section
+     */
+    public void contract() {
         section.setExpanded(false);
     }
 }

--- a/flys-client/src/main/java/de/intevation/flys/client/client/ui/ParameterList.java	Thu Oct 25 14:01:46 2012 +0200
+++ b/flys-client/src/main/java/de/intevation/flys/client/client/ui/ParameterList.java	Thu Oct 25 14:02:39 2012 +0200
@@ -115,6 +115,8 @@
     protected GaugePanel gaugePanel;
     protected Canvas  reportPanel;
 
+    private SectionStack stack;
+
     public ParameterList(FLYS flys, CollectionView cView, String title) {
         super(title);
 
@@ -206,18 +208,11 @@
 
 
     protected SectionStack createSectionStack() {
-        final SectionStack stack = new SectionStack();
+        stack = new SectionStack();
         stack.setHeight100();
         stack.setCanResizeSections(true);
         stack.setVisibilityMode(VisibilityMode.MULTIPLE);
 
-        final SectionStackSection gaugeSection = new SectionStackSection();
-        gaugeSection.setExpanded(false);
-        gaugeSection.setTitle(MSG.gaugePanelTitle());
-        gaugePanel = new GaugePanel(flys, gaugeSection);
-        gaugePanel.setWidth100();
-        gaugePanel.setHeight100();
-
         // This canvas is used to render helper widgets.
         final SectionStackSection helperSection = new SectionStackSection();
         helperSection.setExpanded(false);
@@ -260,7 +255,7 @@
         tablePanel.setWidth100();
         tableSection.setItems(tablePanel);
 
-        stack.setSections(gaugeSection, helperSection, tableSection);
+        stack.setSections(helperSection, tableSection);
 
         return stack;
     }
@@ -758,13 +753,17 @@
         }
         if (art instanceof WINFOArtifact) {
             String river = desc.getRiver();
+
             if (river != null) {
                 renderGaugeInfo(desc.getRiver(), desc.getOldData());
             }
             else {
-                gaugePanel.hide();
+                hideGaugePanel();
             }
         }
+        else {
+            removeGaugePanel();
+        }
 
         addOldDatas(
             desc.getOldData(),
@@ -943,10 +942,51 @@
     }
 
 
+    private void createGaugePanel() {
+        GWT.log("ParameterList - createGaugePanel");
+        if (gaugePanel == null) {
+            gaugePanel = new GaugePanel(flys);
+            gaugePanel.setWidth100();
+            gaugePanel.setHeight100();
+        }
+    }
+
+    private void addGaugePanel() {
+        GWT.log("ParameterList - addGaugePanel");
+        createGaugePanel();
+        stack.addSection(gaugePanel.getSection(), 0);
+    }
+
+    private void showGaugePanel() {
+        GWT.log("ParameterList - showGaugePanel");
+
+        /* Don't add GaugePanel twice */
+        SectionStackSection exists = stack.getSection(GaugePanel.SECTION_ID);
+        if (exists == null) {
+            addGaugePanel();
+        }
+
+        gaugePanel.show();
+    }
+
+    private void hideGaugePanel() {
+        GWT.log("ParameterList - hideGaugePanel");
+
+        if (gaugePanel != null) {
+            gaugePanel.hide();
+        }
+    }
+
+    private void removeGaugePanel() {
+        GWT.log("ParameterList - removeGaugePanel");
+        stack.removeSection(GaugePanel.SECTION_ID);
+    }
+
+
     private void renderGaugeInfo(String river, DataList[] data) {
+        showGaugePanel();
         gaugePanel.setRiver(river);
         gaugePanel.setData(data);
-        gaugePanel.show();
     }
 
 }