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/*
widget-layouting.qdoc
This file is part of GammaRay, the Qt application inspection and manipulation tool.
SPDX-FileCopyrightText: 2016 Klarälvdalens Datakonsult AB, a KDAB Group company <info@kdab.com>
Author: Volker Krause <volker.krause@kdab.com>
SPDX-License-Identifier: GPL-2.0-or-later
Contact KDAB at <info@kdab.com> for commercial licensing options.
*/
// TODO: expand this example to also include size policy issues, but for that we need to
// first be able to actually edit the size policies...
/*!
\example widget-layouting
\title Widget Layouting
\brief Analyze widget layouting behavior.
\ingroup examples-gammaray
This examples shows GammaRay's capabilities in analyzing widget layouting issues.
\section1 Problem
The widget layouting example application shows a complex dialog window that cannot be
resized as small as one would expect.
\section1 Investigation
GammaRay supports several approaches of analyzing widget layouting issues. All of them revolve around the \l{Widget Inspector}.
\section2 In-app widget picking
You can select the widget occupying a specific screen pixel by clicking on the area you are interested in the
target applicationi while holding Ctrl+Shift. This will select the top-most QWidget occupying this space.
This is particularly useful for identifying the "owner" of seemingly empty space. In our example this can
be used to identify the QLabel on the lower left that has an unnecessarily high minimum size set.
\section2 Property inspection
For the selected QWidget or QLayout instance you can look at and edit many layouting-relevant properties in the
\l{Properties} view on the right. Tweaking these values at runtime avoids lengthy recompile and restart cycles just
to verify a specific change.
In our example, we can change the minimum size of the offending QLabel in the lower left to something
more reasonable and immediately verify that the window resizing has improved.
\section2 Bisection layouting problems
A useful approach for identifying more complicated layouting issues is bisecting them, that is, take our parts
of the UI and verify if the problem persists. You can do this at runtime with GammaRay too, without needing
to recompile or restart the target application, by setting the relevant QWidget sub-tree to invisible in the
\l{Properties} view.
In our example, we can use this to exclude the QGroupBox instances at the right side as a possible source
for the window resizing issue. Hiding one of them makes it a lot more apparent that the actual source of the
problem is the QLabel on the lower left.
*/
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