From 98574d61ca1763323baaafe2ab49839964b7e93d Mon Sep 17 00:00:00 2001
From: Alex Ross <alros@microsoft.com>
Date: Tue, 27 Aug 2019 14:02:31 +0200
Subject: [PATCH] Move tree create to happen when the data provider is set

, not when the view is activated.

Fixes #79889
---
 src/vs/workbench/api/browser/mainThreadTreeViews.ts | 4 +++-
 src/vs/workbench/browser/parts/views/customView.ts  | 5 ++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/vs/workbench/api/browser/mainThreadTreeViews.ts b/src/vs/workbench/api/browser/mainThreadTreeViews.ts
index 3c2e1c7080177..db7d95f0d2231 100644
--- a/src/vs/workbench/api/browser/mainThreadTreeViews.ts
+++ b/src/vs/workbench/api/browser/mainThreadTreeViews.ts
@@ -35,9 +35,11 @@ export class MainThreadTreeViews extends Disposable implements MainThreadTreeVie
 			this._dataProviders.set(treeViewId, dataProvider);
 			const viewer = this.getTreeView(treeViewId);
 			if (viewer) {
-				viewer.dataProvider = dataProvider;
+				// Order is important here. The internal tree isn't created until the dataProvider is set.
+				// Set all other properties first!
 				viewer.showCollapseAllAction = !!options.showCollapseAll;
 				viewer.canSelectMany = !!options.canSelectMany;
+				viewer.dataProvider = dataProvider;
 				this.registerListeners(treeViewId, viewer);
 				this._proxy.$setVisible(treeViewId, viewer.visible);
 			} else {
diff --git a/src/vs/workbench/browser/parts/views/customView.ts b/src/vs/workbench/browser/parts/views/customView.ts
index 2fcbf196e0d3a..956b6c10e0ae9 100644
--- a/src/vs/workbench/browser/parts/views/customView.ts
+++ b/src/vs/workbench/browser/parts/views/customView.ts
@@ -228,6 +228,10 @@ export class CustomTreeView extends Disposable implements ITreeView {
 	}
 
 	set dataProvider(dataProvider: ITreeViewDataProvider | undefined) {
+		if (this.tree === undefined) {
+			this.createTree();
+		}
+
 		if (dataProvider) {
 			this._dataProvider = new class implements ITreeViewDataProvider {
 				async getChildren(node: ITreeItem): Promise<ITreeItem[]> {
@@ -578,7 +582,6 @@ export class CustomTreeView extends Disposable implements ITreeView {
 
 	private activate() {
 		if (!this.activated) {
-			this.createTree();
 			this.progressService.withProgress({ location: this.viewContainer.id }, () => this.extensionService.activateByEvent(`onView:${this.id}`))
 				.then(() => timeout(2000))
 				.then(() => {