From 8b99a103b1f9a04368992c5426635907387aaee5 Mon Sep 17 00:00:00 2001
From: Roman Gilg <subdiff@gmail.com>
Date: Wed, 6 Feb 2019 09:23:56 +0100
Subject: [PATCH] [server] Add selectionChanged signal

Summary: This signal notifies a compositor about selection changes on a seat.

Reviewers: #kwin, davidedmundson

Reviewed By: #kwin, davidedmundson

Subscribers: kde-frameworks-devel

Tags: #frameworks

Differential Revision: https://phabricator.kde.org/D15023
---
 src/wayland/seat_interface.cpp |  7 +++++++
 src/wayland/seat_interface.h   | 10 ++++++++++
 2 files changed, 17 insertions(+)

diff --git a/src/wayland/seat_interface.cpp b/src/wayland/seat_interface.cpp
index 0c48e53a98..bfa57b2d98 100644
--- a/src/wayland/seat_interface.cpp
+++ b/src/wayland/seat_interface.cpp
@@ -273,6 +273,7 @@ void SeatInterface::Private::registerDataDevice(DataDeviceInterface *dataDevice)
         if (currentSelection == dataDevice) {
             // current selection is cleared
             currentSelection = nullptr;
+            emit q->selectionChanged(nullptr);
             if (keys.focus.selection) {
                 keys.focus.selection->sendClearSelection();
             }
@@ -405,6 +406,7 @@ void SeatInterface::Private::cancelPreviousSelection(DataDeviceInterface *dataDe
 
 void SeatInterface::Private::updateSelection(DataDeviceInterface *dataDevice, bool set)
 {
+    bool selChanged = currentSelection != dataDevice;
     if (keys.focus.surface && (keys.focus.surface->client() == dataDevice->client())) {
         // cancel the previous selection
         cancelPreviousSelection(dataDevice);
@@ -419,9 +421,13 @@ void SeatInterface::Private::updateSelection(DataDeviceInterface *dataDevice, bo
             } else {
                 keys.focus.selection->sendClearSelection();
                 currentSelection = nullptr;
+                selChanged = true;
             }
         }
     }
+    if (selChanged) {
+        emit q->selectionChanged(currentSelection);
+    }
 }
 
 void SeatInterface::setHasKeyboard(bool has)
@@ -1580,6 +1586,7 @@ void SeatInterface::setSelection(DataDeviceInterface *dataDevice)
             d->keys.focus.selection->sendClearSelection();
         }
     }
+    emit selectionChanged(dataDevice);
 }
 
 }
diff --git a/src/wayland/seat_interface.h b/src/wayland/seat_interface.h
index 85a7afebad..5187c70990 100644
--- a/src/wayland/seat_interface.h
+++ b/src/wayland/seat_interface.h
@@ -644,6 +644,7 @@ public:
     /**
      * @returns The DataDeviceInterface holding the current clipboard selection.
      * @since 5.24
+     * @see selectionChanged
      * @see setSelection
      **/
     DataDeviceInterface *selection() const;
@@ -657,6 +658,7 @@ public:
      *
      * @param dataDevice Sets the current clipboard selection.
      * @see selection
+     * @see selectionChanged
      * @since 5.24
      **/
     void setSelection(DataDeviceInterface *dataDevice);
@@ -682,6 +684,14 @@ Q_SIGNALS:
      **/
     void focusedPointerChanged(KWayland::Server::PointerInterface*);
 
+    /**
+     * Emitted whenever the selection changes
+     * @since 5.56
+     * @see selection
+     * @see setSelection
+     **/
+    void selectionChanged(DataDeviceInterface*);
+
     /**
      * Emitted when a drag'n'drop operation is started
      * @since 5.6