tdf#130857 qt weld: Add a QtInstanceToggleButton

QAbstractButton, which is a base class for both,
QPushButton and QToggleButton already provides the
API needed for toggling.

Use a QToggleButton, as the QPushButton doc [1] says:

> As a general rule, use a push button when the application or dialog
> window performs an action when the user clicks on it (such as Apply,
> Cancel, Close and Help) and when the widget is supposed to have
> a wide, rectangular shape with a text label. Small, typically square
> buttons that change the state of the window rather than performing an
> action (such as the buttons in the top-right corner of the QFileDialog)
> are not command buttons, but tool buttons. Qt provides a special
> class (QToolButton) for these buttons.
>
> If you need toggle behavior (see setCheckable()) or a button that
> auto-repeats the activation signal when being pushed down like the
> arrows in a scroll bar (see setAutoRepeat()), a command button is
> probably not what you want. When in doubt, use a tool button.

For the weld::Toggleable::{g,s}et_inconsistent overrides, it's a bit unclear
to me what these should reasonably do for a button. Just let
them trigger an assert for now.

[1] https://doc.qt.io/qt-6/qpushbutton.html

Change-Id: I51605ee02709bd78f77aeddf9c1993f930fcddd8
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/178848
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

1 files changed, 12 insertions, 0 deletions

diff --git a/vcl/inc/qt6/QtInstanceToggleButton.hxx b/vcl/inc/qt6/QtInstanceToggleButton.hxx
new file mode 100644
index 000000000000..83a0c7ecac77
--- /dev/null
+++ b/vcl/inc/qt6/QtInstanceToggleButton.hxx
@@ -0,0 +1,12 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include "../qt5/QtInstanceToggleButton.hxx"
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */