From 0f315a63f35af17cda05159b8a8ada70141f33b8 Mon Sep 17 00:00:00 2001
From: Carlos Garnacho <carlosg@gnome.org>
Date: Thu, 18 Nov 2021 00:56:44 +0100
Subject: [PATCH] grabHelper: Use Clutter.grab() underneath

This is subject to further possible simplifications. Use Clutter.grab
to redirect input and focus, a fundamental difference here is that
we do redirect input to the topmost owner of the grabhelper stack,
instead of the stage. This is better behaved with the presence of
other grabs, at the cost of some behavioral changes.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2045>
---
 js/ui/grabHelper.js | 33 +++++----------------------------
 1 file changed, 5 insertions(+), 28 deletions(-)

diff --git a/js/ui/grabHelper.js b/js/ui/grabHelper.js
index e70285bde..89e1bee32 100644
--- a/js/ui/grabHelper.js
+++ b/js/ui/grabHelper.js
@@ -6,31 +6,6 @@ const { Clutter, St } = imports.gi;
 const Main = imports.ui.main;
 const Params = imports.misc.params;
 
-let _capturedEventId = 0;
-let _grabHelperStack = [];
-function _onCapturedEvent(actor, event) {
-    let grabHelper = _grabHelperStack[_grabHelperStack.length - 1];
-    return grabHelper.onCapturedEvent(event);
-}
-
-function _pushGrabHelper(grabHelper) {
-    _grabHelperStack.push(grabHelper);
-
-    if (_capturedEventId == 0)
-        _capturedEventId = global.stage.connect('captured-event', _onCapturedEvent);
-}
-
-function _popGrabHelper(grabHelper) {
-    let poppedHelper = _grabHelperStack.pop();
-    if (poppedHelper != grabHelper)
-        throw new Error("incorrect grab helper pop");
-
-    if (_grabHelperStack.length == 0) {
-        global.stage.disconnect(_capturedEventId);
-        _capturedEventId = 0;
-    }
-}
-
 // GrabHelper:
 // @owner: the actor that owns the GrabHelper
 // @params: optional parameters to pass to Main.pushModal()
@@ -209,7 +184,10 @@ var GrabHelper = class GrabHelper {
             if (!Main.pushModal(this._owner, this._modalParams))
                 return false;
 
-            _pushGrabHelper(this);
+            this._capturedEventId = this._owner.connect('captured-event',
+                (actor, event) => {
+                    return this.onCapturedEvent(event);
+                });
         }
 
         this._modalCount++;
@@ -221,8 +199,7 @@ var GrabHelper = class GrabHelper {
         if (this._modalCount > 0)
             return;
 
-        _popGrabHelper(this);
-
+        this._owner.disconnect(this._capturedEventId);
         this._ignoreUntilRelease = false;
 
         Main.popModal(this._owner);