From 22aed2e59d862f10d131f05dbe9aff52b545156c Mon Sep 17 00:00:00 2001
From: Maria Sokolova <maria.sokolova@jetbrains.com>
Date: Wed, 12 Nov 2025 20:11:47 +0000
Subject: [PATCH] [debugger] Do not update XThreadsView if it's not visible

IDEA-381500

Merge-request: IJ-MR-182151
Merged-by: Maria Sokolova <maria.sokolova@jetbrains.com>
(cherry picked from commit 58f3197837b12bade23c35641aca22bda8b691df)


(cherry picked from commit f0c0e5f1c39cb6e48dccd842362f0f8fdf9092ac)

IJ-CR-182318

GitOrigin-RevId: 741ad09f14be497232fc1b1e16fda0143d73e3cc
---
 .../xdebugger/impl/frame/XThreadsView.kt      | 46 ++++++++++++++++---
 1 file changed, 40 insertions(+), 6 deletions(-)

diff --git a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/frame/XThreadsView.kt b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/frame/XThreadsView.kt
index c143adca80ce..647392d198fa 100644
--- a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/frame/XThreadsView.kt
+++ b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/frame/XThreadsView.kt
@@ -1,6 +1,7 @@
 // Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.xdebugger.impl.frame
 
+import com.intellij.openapi.application.EDT
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.util.NlsSafe
 import com.intellij.platform.debugger.impl.rpc.XDebugSessionApi
@@ -18,15 +19,26 @@ import com.intellij.xdebugger.impl.ui.tree.XDebuggerTree
 import com.intellij.xdebugger.impl.ui.tree.XDebuggerTreePanel
 import com.intellij.xdebugger.impl.ui.tree.nodes.XValueContainerNode
 import com.intellij.xdebugger.impl.ui.tree.nodes.XValueNodeImpl
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.FlowPreview
+import kotlinx.coroutines.channels.BufferOverflow
+import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.collectLatest
+import kotlinx.coroutines.flow.debounce
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import org.jetbrains.annotations.ApiStatus
 import java.awt.Component
+import java.awt.event.HierarchyEvent
 import javax.swing.JPanel
 
+@OptIn(FlowPreview::class)
 @ApiStatus.Internal
 class XThreadsView(project: Project, session: XDebugSessionProxy) : XDebugView() {
 
+  private val rebuildRequests = MutableSharedFlow<Unit>(replay = 1, extraBufferCapacity = 1, onBufferOverflow = BufferOverflow.DROP_OLDEST)
+  private var wasShowing = false
+
   @ApiStatus.Obsolete
   constructor(project: Project, session: XDebugSession) : this(project, session.asProxy())
 
@@ -52,16 +64,36 @@ class XThreadsView(project: Project, session: XDebugSessionProxy) : XDebugView()
       }
     }.install(tree)
 
+    panel.addHierarchyListener { e ->
+      if ((e.changeFlags and HierarchyEvent.SHOWING_CHANGED.toLong()) > 0) {
+        val isCurrentlyShowing = panel.isShowing
+        if (!wasShowing && isCurrentlyShowing) {
+          requestRebuild()
+        }
+        wasShowing = isCurrentlyShowing
+      }
+    }
+
     subscribeToThreadRefreshEvents(session)
+
+    session.coroutineScope.launch {
+      rebuildRequests
+        .debounce(200)
+        .collectLatest {
+          withContext(Dispatchers.EDT) {
+            if (panel.isShowing) {
+              tree.setRoot(XThreadsRootNode(tree, session), false)
+            }
+          }
+        }
+    }
   }
 
   private fun subscribeToThreadRefreshEvents(session: XDebugSessionProxy) {
     session.coroutineScope.launch {
       XDebugSessionApi.getInstance().getUiUpdateEventsFlow(session.id)
         .collectLatest {
-          DebuggerUIUtil.invokeLater {
-            tree.setRoot(XThreadsRootNode(tree, session), false)
-          }
+          requestRebuild()
         }
     }
   }
@@ -74,6 +106,10 @@ class XThreadsView(project: Project, session: XDebugSessionProxy) : XDebugView()
 
   fun getDefaultFocusedComponent(): XDebuggerTree = tree
 
+  private fun requestRebuild() {
+    rebuildRequests.tryEmit(Unit)
+  }
+
   override fun clear() {
     DebuggerUIUtil.invokeLater {
       tree.setRoot(object : XValueContainerNode<XValueContainer>(tree, null, true, object : XValueContainer() {}) {}, false)
@@ -98,9 +134,7 @@ class XThreadsView(project: Project, session: XDebugSessionProxy) : XDebugView()
       cancelClear()
       clear()
     }
-    DebuggerUIUtil.invokeLater {
-      tree.setRoot(XThreadsRootNode(tree, session), false)
-    }
+    requestRebuild()
   }
 
   override fun dispose() {