From 886fe7e69f61fff5c58e1d84c640398c97a4c1ab Mon Sep 17 00:00:00 2001
From: Linus Groh <mail@linusgroh.de>
Date: Sun, 6 Dec 2020 20:53:29 +0000
Subject: [PATCH] LibGUI: Allow GUI::Action to swallow key events when disabled

Sometimes an action should be disabled and the KeyEvent not posted to
the app's event loop nonetheless. In other words the action swallows the
KeyEvent without being activated.

Specific use-case: Terminal's Ctrl+Shift+{C,V}.
---
 Libraries/LibGUI/Action.h                   |  4 ++++
 Libraries/LibGUI/WindowServerConnection.cpp | 10 +++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/Libraries/LibGUI/Action.h b/Libraries/LibGUI/Action.h
index 44bb3ec223..8b1f9f4d1d 100644
--- a/Libraries/LibGUI/Action.h
+++ b/Libraries/LibGUI/Action.h
@@ -132,6 +132,9 @@ public:
     }
     void set_checked(bool);
 
+    bool swallow_key_event_when_disabled() const { return m_swallow_key_event_when_disabled; }
+    void set_swallow_key_event_when_disabled(bool swallow) { m_swallow_key_event_when_disabled = swallow; }
+
     void register_button(Badge<Button>, Button&);
     void unregister_button(Badge<Button>, Button&);
     void register_menu_item(Badge<MenuItem>, MenuItem&);
@@ -159,6 +162,7 @@ private:
     bool m_enabled { true };
     bool m_checkable { false };
     bool m_checked { false };
+    bool m_swallow_key_event_when_disabled { false };
     ShortcutScope m_scope { ShortcutScope::None };
 
     HashTable<Button*> m_buttons;
diff --git a/Libraries/LibGUI/WindowServerConnection.cpp b/Libraries/LibGUI/WindowServerConnection.cpp
index b1bb2703c4..20629dda95 100644
--- a/Libraries/LibGUI/WindowServerConnection.cpp
+++ b/Libraries/LibGUI/WindowServerConnection.cpp
@@ -173,9 +173,13 @@ void WindowServerConnection::handle(const Messages::WindowClient::KeyDown& messa
 #endif
     }
 
-    if (action && action->is_enabled()) {
-        action->activate();
-        return;
+    if (action) {
+        if (action->is_enabled()) {
+            action->activate();
+            return;
+        }
+        if (action->swallow_key_event_when_disabled())
+            return;
     }
 
     bool focused_widget_accepts_emoji_input = window->focused_widget() && window->focused_widget()->accepts_emoji_input();