[wayland] Change keyboard focus window when active window changes

We used to change it only on keypresses. This resulted in the strange
situation that e.g. the input method virtual keyboard doesn't show up
until one presses a real key, because e.g. maliit only activates the
keyboard if there is an active focus object in the Qt application.

input.cpp

@@ -256,6 +256,7 @@ InputRedirection::InputRedirection(QObject *parent)
         }
     }
 #endif
+    connect(kwinApp(), &Application::workspaceCreated, this, &InputRedirection::setupWorkspace);
 }
 
 InputRedirection::~InputRedirection()
@@ -263,6 +264,15 @@ InputRedirection::~InputRedirection()
     s_self = NULL;
 }
 
+void InputRedirection::setupWorkspace()
+{
+#if HAVE_WAYLAND
+    if (waylandServer()) {
+        connect(workspace(), &Workspace::clientActivated, this, &InputRedirection::updateKeyboardWindow);
+    }
+#endif
+}
+
 #if HAVE_WAYLAND
 static KWayland::Server::SeatInterface *findSeat()
 {
@@ -732,6 +742,32 @@ void InputRedirection::processPointerAxis(InputRedirection::PointerAxis axis, qr
 #endif
 }
 
+void InputRedirection::updateKeyboardWindow()
+{
+#if HAVE_WAYLAND
+    if (!workspace()) {
+        return;
+    }
+    if (auto seat = findSeat()) {
+        // TODO: this needs better integration
+        // check unmanaged
+        Toplevel *t = nullptr;
+        if (!workspace()->unmanagedList().isEmpty()) {
+            // TODO: better check whether this unmanaged should get the key event
+            t = workspace()->unmanagedList().first();
+        }
+        if (!t) {
+            t = workspace()->activeClient();
+        }
+        if (t && t->surface()) {
+            if (t->surface() != seat->focusedKeyboardSurface()) {
+                seat->setFocusedKeyboardSurface(t->surface());
+            }
+        }
+    }
+#endif
+}
+
 void InputRedirection::processKeyboardKey(uint32_t key, InputRedirection::KeyboardKeyState state, uint32_t time)
 {
 #if HAVE_XKB
@@ -786,22 +822,7 @@ void InputRedirection::processKeyboardKey(uint32_t key, InputRedirection::Keyboa
 #if HAVE_WAYLAND
     if (auto seat = findSeat()) {
         seat->setTimestamp(time);
-        // TODO: this needs better integration
-        // check unmanaged
-        Toplevel *t = nullptr;
-        if (!workspace()->unmanagedList().isEmpty()) {
-            // TODO: better check whether this unmanaged should get the key event
-            t = workspace()->unmanagedList().first();
-        }
-        if (!t) {
-            t = workspace()->activeClient();
-        }
-        if (t && t->surface()) {
-            if (t->surface() != seat->focusedKeyboardSurface()) {
-                seat->setFocusedKeyboardSurface(t->surface());
-            }
-            state == InputRedirection::KeyboardKeyPressed ? seat->keyPressed(key) : seat->keyReleased(key);
-        }
+        state == InputRedirection::KeyboardKeyPressed ? seat->keyPressed(key) : seat->keyReleased(key);
     }
 #endif
 }

input.h

@@ -197,6 +197,8 @@ private:
     void pointerInternalWindowVisibilityChanged(bool visible);
     void installCursorFromDecoration();
     bool areButtonsPressed() const;
+    void updateKeyboardWindow();
+    void setupWorkspace();
     QPointF m_globalPointer;
     QHash<uint32_t, PointerButtonState> m_pointerButtons;
 #if HAVE_XKB