SLI-585 Rework SonarLint tool window layout

* Splitter layout will adapt depending on the docking position
* Default split value is 50%
* Removed useless borders on some panels
* Splitter now have a 1px border to "grab"

src/main/java/org/sonarlint/intellij/ui/AbstractIssuesPanel.java

@@ -20,7 +20,6 @@
 package org.sonarlint.intellij.ui;
 
 import com.intellij.ide.OccurenceNavigator;
-import com.intellij.ide.util.PropertiesComponent;
 import com.intellij.openapi.actionSystem.ActionGroup;
 import com.intellij.openapi.actionSystem.ActionManager;
 import com.intellij.openapi.actionSystem.ActionToolbar;
@@ -29,12 +28,12 @@
 import com.intellij.openapi.fileEditor.OpenFileDescriptor;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.SimpleToolWindowPanel;
-import com.intellij.openapi.ui.Splitter;
 import com.intellij.tools.SimpleActionGroup;
 import com.intellij.ui.ScrollPaneFactory;
 import com.intellij.ui.components.JBTabbedPane;
 import com.intellij.ui.treeStructure.Tree;
 import com.intellij.util.ui.tree.TreeUtil;
+
 import java.awt.event.FocusAdapter;
 import java.awt.event.FocusEvent;
 import java.awt.event.KeyAdapter;
@@ -43,14 +42,14 @@
 import javax.annotation.CheckForNull;
 import javax.annotation.Nullable;
 import javax.swing.Box;
-import javax.swing.JComponent;
 import javax.swing.JScrollPane;
 import javax.swing.ScrollPaneConstants;
 import javax.swing.tree.DefaultMutableTreeNode;
 import javax.swing.tree.DefaultTreeModel;
 import javax.swing.tree.TreeNode;
 import javax.swing.tree.TreePath;
 import javax.swing.tree.TreeSelectionModel;
+
 import org.sonarlint.intellij.editor.EditorDecorator;
 import org.sonarlint.intellij.issue.LiveIssue;
 import org.sonarlint.intellij.ui.nodes.AbstractNode;
@@ -89,36 +88,22 @@ public void refreshToolbar() {
 
   private void createTabs() {
     // Flows panel with tree
-    JScrollPane flowsPanel = ScrollPaneFactory.createScrollPane(flowsTree);
+    JScrollPane flowsPanel = ScrollPaneFactory.createScrollPane(flowsTree, true);
     flowsPanel.getVerticalScrollBar().setUnitIncrement(10);
 
     // Rule panel
     rulePanel = new SonarLintRulePanel(project);
-    JScrollPane scrollableRulePanel = ScrollPaneFactory.createScrollPane(
-      rulePanel.getPanel(),
-      ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
-      ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
+    JScrollPane scrollableRulePanel = ScrollPaneFactory.createScrollPane(rulePanel.getPanel(), true);
+
+    scrollableRulePanel.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
+    scrollableRulePanel.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED);
     scrollableRulePanel.getVerticalScrollBar().setUnitIncrement(10);
 
     detailsTab = new JBTabbedPane();
     detailsTab.insertTab("Rule", null, scrollableRulePanel, "Details about the rule", RULE_TAB_INDEX);
     detailsTab.insertTab("Locations", null, flowsPanel, "All locations involved in the issue", LOCATIONS_TAB_INDEX);
   }
 
-  protected JComponent createSplitter(JComponent c1, JComponent c2, String proportionProperty, boolean vertical, float defaultSplit) {
-    float savedProportion = PropertiesComponent.getInstance(project).getFloat(proportionProperty, defaultSplit);
-
-    final Splitter splitter = new Splitter(vertical);
-    splitter.setFirstComponent(c1);
-    splitter.setSecondComponent(c2);
-    splitter.setProportion(savedProportion);
-    splitter.setHonorComponentsMinimumSize(true);
-    splitter.addPropertyChangeListener(Splitter.PROP_PROPORTION,
-      evt -> PropertiesComponent.getInstance(project).setValue(proportionProperty, Float.toString(splitter.getProportion())));
-
-    return splitter;
-  }
-
   protected void issueTreeSelectionChanged() {
     IssueNode[] selectedNodes = tree.getSelectedNodes(IssueNode.class, null);
     if (selectedNodes.length > 0) {
@@ -184,7 +169,8 @@ public void keyPressed(KeyEvent e) {
       }
     });
     tree.addFocusListener(new FocusAdapter() {
-      @Override public void focusGained(FocusEvent e) {
+      @Override
+      public void focusGained(FocusEvent e) {
         if (!e.isTemporary()) {
           issueTreeSelectionChanged();
         }
@@ -211,7 +197,8 @@ private OccurenceNavigator.OccurenceInfo occurrence(@Nullable IssueNode node) {
       -1);
   }
 
-  @Override public boolean hasNextOccurence() {
+  @Override
+  public boolean hasNextOccurence() {
     // relies on the assumption that a TreeNodes will always be the last row in the table view of the tree
     TreePath path = tree.getSelectionPath();
     if (path == null) {
@@ -225,7 +212,8 @@ private OccurenceNavigator.OccurenceInfo occurrence(@Nullable IssueNode node) {
     }
   }
 
-  @Override public boolean hasPreviousOccurence() {
+  @Override
+  public boolean hasPreviousOccurence() {
     TreePath path = tree.getSelectionPath();
     if (path == null) {
       return false;
@@ -259,18 +247,20 @@ public OccurenceNavigator.OccurenceInfo goPreviousOccurence() {
     return occurrence(treeBuilder.getPreviousIssue((AbstractNode) path.getLastPathComponent()));
   }
 
-  @Override public String getNextOccurenceActionName() {
+  @Override
+  public String getNextOccurenceActionName() {
     return "Next Issue";
   }
 
-  @Override public String getPreviousOccurenceActionName() {
+  @Override
+  public String getPreviousOccurenceActionName() {
     return "Previous Issue";
   }
 
   public void setSelectedIssue(LiveIssue issue) {
     DefaultMutableTreeNode issueNode = TreeUtil.findNode(((DefaultMutableTreeNode) tree.getModel().getRoot()),
       (node) -> node instanceof IssueNode && ((IssueNode) node).issue().equals(issue));
-    if(issueNode == null) {
+    if (issueNode == null) {
       return;
     }
     tree.setSelectionPath(null);

src/main/java/org/sonarlint/intellij/ui/SonarLintAnalysisResultsPanel.java

@@ -32,6 +32,8 @@
 import org.sonarlint.intellij.messages.StatusListener;
 import org.sonarlint.intellij.util.SonarLintActions;
 
+import static org.sonarlint.intellij.ui.SonarLintToolWindowFactory.createSplitter;
+
 public class SonarLintAnalysisResultsPanel extends AbstractIssuesPanel implements Disposable {
   private static final String SPLIT_PROPORTION_PROPERTY = "SONARLINT_ANALYSIS_RESULTS_SPLIT_PROPORTION";
 
@@ -50,7 +52,7 @@ public SonarLintAnalysisResultsPanel(Project project) {
     setToolbar(createActionGroup());
 
     // Put everything together
-    super.setContent(createSplitter(issuesPanel, detailsTab, SPLIT_PROPORTION_PROPERTY, false, 0.65f));
+    super.setContent(createSplitter(project, this, this, issuesPanel, detailsTab, SPLIT_PROPORTION_PROPERTY, 0.5f));
 
     // Subscribe to events
     subscribeToEvents();

src/main/java/org/sonarlint/intellij/ui/SonarLintHotspotDescriptionPanel.java

@@ -58,7 +58,6 @@ public SonarLintHotspotDescriptionPanel(Project project) {
     styleSheet.addRule("td.pad {padding: 0px 10px 0px 0px;}");
 
     panel = new JPanel(new BorderLayout());
-    panel.setBorder(IdeBorderFactory.createBorder(SideBorder.LEFT));
 
     JComponent titleComp = new JLabel("Select a hotspot to see more details", SwingConstants.CENTER);
     panel.add(titleComp, BorderLayout.CENTER);

src/main/java/org/sonarlint/intellij/ui/SonarLintHotspotsPanel.java

@@ -19,19 +19,22 @@
  */
 package org.sonarlint.intellij.ui;
 
-import com.intellij.ide.util.PropertiesComponent;
+import com.intellij.openapi.Disposable;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.SimpleToolWindowPanel;
-import com.intellij.openapi.ui.Splitter;
 import com.intellij.ui.ScrollPaneFactory;
 import com.intellij.ui.components.JBTabbedPane;
+
 import javax.swing.JComponent;
 import javax.swing.JScrollPane;
 import javax.swing.ScrollPaneConstants;
+
 import org.sonarlint.intellij.issue.hotspot.LocalHotspot;
 import org.sonarsource.sonarlint.core.serverapi.hotspot.ServerHotspot;
 
-public class SonarLintHotspotsPanel extends SimpleToolWindowPanel {
+import static org.sonarlint.intellij.ui.SonarLintToolWindowFactory.createSplitter;
+
+public class SonarLintHotspotsPanel extends SimpleToolWindowPanel implements Disposable {
   private static final String SPLIT_PROPORTION_PROPERTY = "SONARLINT_HOTSPOTS_SPLIT_PROPORTION";
   private static final float DEFAULT_SPLIT_PROPORTION = 0.5f;
 
@@ -58,32 +61,17 @@ public SonarLintHotspotsPanel(Project project) {
     hotspotDetailsTab.addTab("Details", null, scrollable(detailsPanel.getPanel()), "Details about the hotspot");
     hotspotDetailsTab.setVisible(false);
 
-    super.setContent(createSplitter(hotspotsListPanel.getPanel(), hotspotDetailsTab, SPLIT_PROPORTION_PROPERTY, project));
+    super.setContent(createSplitter(project, this, this, hotspotsListPanel.getPanel(), hotspotDetailsTab, SPLIT_PROPORTION_PROPERTY, DEFAULT_SPLIT_PROPORTION));
   }
 
   private static JScrollPane scrollable(JComponent component) {
-    JScrollPane scrollableRulePanel = ScrollPaneFactory.createScrollPane(
-      component,
-      ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
-      ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
+    JScrollPane scrollableRulePanel = ScrollPaneFactory.createScrollPane(component, true);
+    scrollableRulePanel.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
+    scrollableRulePanel.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED);
     scrollableRulePanel.getVerticalScrollBar().setUnitIncrement(10);
     return scrollableRulePanel;
   }
 
-  protected JComponent createSplitter(JComponent c1, JComponent c2, String proportionProperty, Project project) {
-    float savedProportion = PropertiesComponent.getInstance(project).getFloat(proportionProperty, DEFAULT_SPLIT_PROPORTION);
-
-    final Splitter splitter = new Splitter(false);
-    splitter.setFirstComponent(c1);
-    splitter.setSecondComponent(c2);
-    splitter.setProportion(savedProportion);
-    splitter.setHonorComponentsMinimumSize(true);
-    splitter.addPropertyChangeListener(Splitter.PROP_PROPORTION,
-      evt -> PropertiesComponent.getInstance(project).setValue(proportionProperty, Float.toString(splitter.getProportion())));
-
-    return splitter;
-  }
-
   public void setHotspot(LocalHotspot hotspot) {
     hotspotDetailsTab.setVisible(true);
     hotspotsListPanel.setHotspot(hotspot);
@@ -94,4 +82,8 @@ public void setHotspot(LocalHotspot hotspot) {
     detailsPanel.setDetails(hotspot);
   }
 
+  @Override
+  public void dispose() {
+    // Nothing to do
+  }
 }

src/main/java/org/sonarlint/intellij/ui/SonarLintIssuesPanel.java

@@ -19,14 +19,16 @@
  */
 package org.sonarlint.intellij.ui;
 
+import com.intellij.openapi.Disposable;
 import com.intellij.openapi.actionSystem.ActionManager;
 import com.intellij.openapi.actionSystem.AnAction;
 import com.intellij.openapi.actionSystem.CommonDataKeys;
-import com.intellij.openapi.actionSystem.DataProvider;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.ui.JBSplitter;
 import com.intellij.ui.ScrollPaneFactory;
 import com.intellij.util.ui.tree.TreeUtil;
+
 import java.awt.BorderLayout;
 import java.awt.EventQueue;
 import java.util.ArrayList;
@@ -35,14 +37,18 @@
 import java.util.List;
 import javax.annotation.Nullable;
 import javax.swing.JPanel;
+
 import org.jetbrains.annotations.NonNls;
 import org.sonarlint.intellij.issue.LiveIssue;
 import org.sonarlint.intellij.util.SonarLintActions;
 import org.sonarlint.intellij.util.SonarLintUtils;
 
-public class SonarLintIssuesPanel extends AbstractIssuesPanel implements DataProvider {
+import static org.sonarlint.intellij.ui.SonarLintToolWindowFactory.createSplitter;
+
+public class SonarLintIssuesPanel extends AbstractIssuesPanel implements Disposable {
   private static final String SPLIT_PROPORTION_PROPERTY = "SONARLINT_ISSUES_SPLIT_PROPORTION";
   private final CurrentFileController scope;
+  private final JBSplitter splitter;
 
   public SonarLintIssuesPanel(Project project, CurrentFileController scope) {
     super(project);
@@ -54,11 +60,16 @@ public SonarLintIssuesPanel(Project project, CurrentFileController scope) {
     issuesPanel.add(ScrollPaneFactory.createScrollPane(tree), BorderLayout.CENTER);
     issuesPanel.add(new AutoTriggerStatusPanel(project).getPanel(), BorderLayout.SOUTH);
 
-    super.setContent(createSplitter(issuesPanel, detailsTab, SPLIT_PROPORTION_PROPERTY, false, 0.65f));
-
+    splitter = createSplitter(project, this, this, issuesPanel, detailsTab, SPLIT_PROPORTION_PROPERTY, 0.5f);
+    super.setContent(splitter);
     subscribeToEvents();
   }
 
+  @Override
+  public void dispose() {
+    // Nothing to do
+  }
+
   private static Collection<AnAction> actions() {
     SonarLintActions sonarLintActions = SonarLintActions.getInstance();
     List<AnAction> list = new ArrayList<>();

src/main/java/org/sonarlint/intellij/ui/SonarLintRulePanel.java

@@ -67,7 +67,6 @@ public class SonarLintRulePanel {
   public SonarLintRulePanel(Project project) {
     this.project = project;
     panel = new JPanel(new BorderLayout());
-    panel.setBorder(IdeBorderFactory.createBorder(SideBorder.LEFT));
     setRuleKey(null);
     show();
   }

src/main/java/org/sonarlint/intellij/ui/SonarLintToolWindowFactory.java

@@ -19,13 +19,22 @@
  */
 package org.sonarlint.intellij.ui;
 
+import com.intellij.openapi.Disposable;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.wm.ToolWindow;
+import com.intellij.openapi.wm.ToolWindowAnchor;
 import com.intellij.openapi.wm.ToolWindowFactory;
+import com.intellij.openapi.wm.ToolWindowManager;
 import com.intellij.openapi.wm.ToolWindowType;
+import com.intellij.openapi.wm.ex.ToolWindowManagerListener;
+import com.intellij.ui.JBSplitter;
+import com.intellij.ui.OnePixelSplitter;
 import com.intellij.ui.content.Content;
 import com.intellij.ui.content.ContentManager;
+
+import javax.swing.JComponent;
+
 import org.jetbrains.annotations.NotNull;
 import org.sonarlint.intellij.actions.SonarLintToolWindow;
 import org.sonarlint.intellij.issue.IssueManager;
@@ -65,6 +74,40 @@ public void createToolWindowContent(Project project, final ToolWindow toolWindow
     }
   }
 
+  public static JBSplitter createSplitter(Project project, JComponent parentComponent, Disposable parentDisposable, JComponent c1, JComponent c2, String proportionProperty,
+    float defaultSplit) {
+    JBSplitter splitter = new OnePixelSplitter(splitVertically(project), proportionProperty, defaultSplit);
+    splitter.setFirstComponent(c1);
+    splitter.setSecondComponent(c2);
+    splitter.setHonorComponentsMinimumSize(true);
+
+    final ToolWindowManagerListener listener = new ToolWindowManagerListener() {
+      @Override
+      public void stateChanged(@NotNull ToolWindowManager toolWindowManager) {
+        splitter.setOrientation(splitVertically(project));
+        parentComponent.revalidate();
+        parentComponent.repaint();
+      }
+    };
+    project.getMessageBus().connect(parentDisposable).subscribe(ToolWindowManagerListener.TOPIC, listener);
+    Disposer.register(parentDisposable, () -> {
+      parentComponent.remove(splitter);
+      splitter.dispose();
+    });
+
+    return splitter;
+  }
+
+  public static boolean splitVertically(Project project) {
+    final ToolWindow toolWindow = ToolWindowManager.getInstance(project).getToolWindow(SonarLintToolWindowFactory.TOOL_WINDOW_ID);
+    boolean splitVertically = false;
+    if (toolWindow != null) {
+      final ToolWindowAnchor anchor = toolWindow.getAnchor();
+      splitVertically = anchor == ToolWindowAnchor.LEFT || anchor == ToolWindowAnchor.RIGHT;
+    }
+    return splitVertically;
+  }
+
   private static void addIssuesTab(Project project, @NotNull ContentManager contentManager) {
     IssueManager issueManager = getService(project, IssueManager.class);
     CurrentFileController scope = new CurrentFileController(project, issueManager);
@@ -95,16 +138,15 @@ private static void addAnalysisResultsTab(Project project, @NotNull ContentManag
   private static void addTaintIssuesTab(Project project, @NotNull ContentManager contentManager) {
     TaintVulnerabilitiesPanel vulnerabilitiesPanel = new TaintVulnerabilitiesPanel(project);
     Content analysisResultsContent = contentManager.getFactory()
-            .createContent(
-                    vulnerabilitiesPanel,
-                    buildVulnerabilitiesTabName(0),
-                    false);
+      .createContent(
+        vulnerabilitiesPanel,
+        buildVulnerabilitiesTabName(0),
+        false);
     analysisResultsContent.setCloseable(false);
     contentManager.addDataProvider(vulnerabilitiesPanel);
     contentManager.addContent(analysisResultsContent);
   }
 
-
   private static void addLogTab(Project project, ToolWindow toolWindow) {
     Content logContent = toolWindow.getContentManager().getFactory()
       .createContent(