From 1893964afa23a04df463798559f75bb0eeff0aba Mon Sep 17 00:00:00 2001
From: Kirill Kirichenko <kirill.kirichenko@jetbrains.com>
Date: Tue, 14 Jan 2020 11:54:03 +0300
Subject: [PATCH] IDEA-228866 Add theme switch delay and restoration of
 original theme on Escape

GitOrigin-RevId: 4498e1a376c921d0b20785a996c1418a4e7a5608
---
 .../ide/actions/QuickChangeLookAndFeel.java   | 27 +++++++++++++++----
 .../util/resources/misc/registry.properties   |  2 ++
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/platform/platform-impl/src/com/intellij/ide/actions/QuickChangeLookAndFeel.java b/platform/platform-impl/src/com/intellij/ide/actions/QuickChangeLookAndFeel.java
index 498a1dde7c06..39454b5f7ee9 100644
--- a/platform/platform-impl/src/com/intellij/ide/actions/QuickChangeLookAndFeel.java
+++ b/platform/platform-impl/src/com/intellij/ide/actions/QuickChangeLookAndFeel.java
@@ -10,11 +10,14 @@ import com.intellij.openapi.actionSystem.*;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.project.DumbAwareAction;
 import com.intellij.openapi.project.Project;
+import com.intellij.openapi.ui.popup.JBPopupListener;
+import com.intellij.openapi.ui.popup.LightweightWindowEvent;
 import com.intellij.openapi.ui.popup.ListPopup;
 import com.intellij.openapi.util.Condition;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.util.Ref;
 import com.intellij.openapi.util.registry.Registry;
+import com.intellij.util.Alarm;
 import com.intellij.util.ui.StartupUiUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -25,32 +28,46 @@ import javax.swing.*;
  * @author max
  */
 public class QuickChangeLookAndFeel extends QuickSwitchSchemeAction {
+  private UIManager.LookAndFeelInfo initialLaf;
+  private final Alarm switchAlarm = new Alarm();
 
   @Override
   protected void fillActions(Project project, @NotNull DefaultActionGroup group, @NotNull DataContext dataContext) {
     LafManager lafMan = LafManager.getInstance();
     UIManager.LookAndFeelInfo[] lfs = lafMan.getInstalledLookAndFeels();
-    UIManager.LookAndFeelInfo currentLaf = lafMan.getCurrentLookAndFeel();
+    initialLaf = lafMan.getCurrentLookAndFeel();
 
     for (UIManager.LookAndFeelInfo lf : lfs) {
-      group.add(new LafChangeAction(lf, currentLaf == lf));
+      group.add(new LafChangeAction(lf, initialLaf == lf));
     }
   }
 
   @Override
   protected void showPopup(AnActionEvent e, ListPopup popup) {
+    switchAlarm.cancelAllRequests();
     if (Registry.is("ide.instant.theme.switch")) {
-      LafManager lafMan = LafManager.getInstance();
       popup.addListSelectionListener(event -> {
         JList list = (JList)event.getSource();
         Object item = list.getSelectedValue();
         if (item instanceof AnActionHolder) {
-          LafChangeAction action = (LafChangeAction)((AnActionHolder)item).getAction();
-          switchLafAndUpdateUI(lafMan, action.myLookAndFeelInfo, false);
+          switchAlarm.cancelAllRequests();
+          switchAlarm.addRequest(() -> {
+            LafChangeAction action = (LafChangeAction)((AnActionHolder)item).getAction();
+            switchLafAndUpdateUI(LafManager.getInstance(), action.myLookAndFeelInfo, false);
+          }, Registry.get("ide.instant.theme.switch.delay").asInteger());
         }
       });
     }
 
+    popup.addListener(new JBPopupListener() {
+      @Override
+      public void onClosed(@NotNull LightweightWindowEvent event) {
+        if (Registry.is("ide.instant.theme.switch") && !event.isOk()) {
+          switchLafAndUpdateUI(LafManager.getInstance(), initialLaf, false);
+        }
+      }
+    });
+
     super.showPopup(e, popup);
   }
 
diff --git a/platform/util/resources/misc/registry.properties b/platform/util/resources/misc/registry.properties
index 945bbda3428a..6d2190074c3f 100644
--- a/platform/util/resources/misc/registry.properties
+++ b/platform/util/resources/misc/registry.properties
@@ -1169,6 +1169,8 @@ ide.find.in.file.highlight.usages=false
 ide.find.in.file.highlight.usages.description=Delegate FindUsagesInFile action to HighlightUsagesInFile
 ide.instant.theme.switch=true
 ide.instant.theme.switch.description=Switch theme in the quick switcher instantly, upon selection
+ide.instant.theme.switch.delay=500
+ide.instant.theme.switch.delay.description=Instant theme switch delay in milliseconds
 
 git.execute.with.mediator=true
 git.execute.with.mediator.description=Use wrapper executable on Windows to support soft Git process cancellation.