Differential D24361 Diff 67699 kcms/style/previewitem.cpp

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kcms/style/previewitem.cpp

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1​/*
2​ * Copyright © 2003-2007 Fredrik Höglund <fredrik@kde.org>
3​ * Copyright 2019 Kai Uwe Broulik <kde@broulik.de>
4​ *
5​ * This program is free software; you can redistribute it and/or
6​ * modify it under the terms of the GNU General Public
7​ * License version 2 as published by the Free Software Foundation.
8​ *
9​ * This program is distributed in the hope that it will be useful,
10​ * but WITHOUT ANY WARRANTY; without even the implied warranty of
11​ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12​ * General Public License for more details.
13​ *
14​ * You should have received a copy of the GNU General Public License
15​ * along with this program; see the file COPYING. If not, write to
16​ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17​ * Boston, MA 02110-1301, USA.
18​ */
19​
20​#include "previewitem.h"
21​
22​#include <QHoverEvent>
23​#include <QMouseEvent>
24​#include <QPainter>
25​#include <QPixmapCache>
26​#include <QQuickWindow>
27​#include <QStyleFactory>
28​#include <QWidget>
29​
30​#include <KColorScheme>
31​#include <KSharedConfig>
32​
33​PreviewItem::PreviewItem(QQuickItem *parent)
34​ : QQuickPaintedItem(parent)
35​{
36​ setAcceptHoverEvents(true);
37​
38​ // HACK QtCurve deadlocks on application teardown when the Q_GLOBAL_STATIC QFactoryLoader
39​ // in QStyleFactory is destroyed which destroys all loaded styles prompting QtCurve
40​ // to disconnect from DBus stalling the application.
41​ // This also happens before any of the KCM objects are destroyed, so our only chance
42​ // is cleaning up in response to aboutToQuit
43​ connect(qApp, &QApplication::aboutToQuit, this, [this] {
44​ m_style.reset();
45​ });
46​}
47​
48​PreviewItem::~PreviewItem() = default;
49​
50​void PreviewItem::componentComplete()
51​{
52​ QQuickPaintedItem::componentComplete();
53​ reload();
54​}
55​
56​bool PreviewItem::eventFilter(QObject *watched, QEvent *event)
57​{
58​ if (watched == m_widget.data()) {
59​ switch (event->type()) {
60​ case QEvent::Show:
61​ case QEvent::UpdateRequest:
62​ update();
63​ break;
64​ default:
65​ break;
66​ }
67​ }
68​
69​ return QQuickPaintedItem::eventFilter(watched, event);
70​}
71​
72​QString PreviewItem::styleName() const
73​{
74​ return m_styleName;
75​}
76​
77​void PreviewItem::setStyleName(const QString &styleName)
78​{
79​ if (m_styleName == styleName) {
80​ return;
81​ }
82​
83​ m_styleName = styleName;
84​ reload();
85​ emit styleNameChanged();
86​}
87​
88​bool PreviewItem::isValid() const
89​{
90​ return m_style && m_widget;
91​}
92​
93​void setStyleRecursively(QWidget *widget, QStyle *style)
94​{
95​ // Don't let styles kill the palette for other styles being previewed.
96​ widget->setPalette(QPalette());
97​
98​ QPalette newPalette(KColorScheme::createApplicationPalette(KSharedConfig::openConfig()));
99​ style->polish(newPalette);
100​
101​ widget->setPalette(newPalette);
102​
103​ widget->setStyle(style);
104​
105​ const auto children = widget->children();
106​ for (QObject *child : children) {
107​ if (child->isWidgetType()) {
108​ setStyleRecursively(static_cast<QWidget *>(child), style);
109​ }
110​ }
111​}
112​
113​void PreviewItem::reload()
114​{
115​ if (!isComponentComplete()) {
116​ return;
117​ }
118​
119​ const bool oldValid = isValid();
120​
121​ m_style.reset(QStyleFactory::create(m_styleName));
122​ if (!m_style) {
123​ qWarning() << "Failed to load style" << m_styleName;
124​ if (oldValid != isValid()) {
125​ emit validChanged();
126​ }
127​ return;
128​ }
129​
130​ m_widget.reset(new QWidget);
131​ // Don't actually show the widget as a separate window when calling show()
132​ m_widget->setAttribute(Qt::WA_DontShowOnScreen);
133​ // Do not wait for this widget to close before the app closes
134​ m_widget->setAttribute(Qt::WA_QuitOnClose, false);
135​
136​ m_ui.setupUi(m_widget.data());
137​
138​ // Prevent Qt from wrongly caching radio button images
139​ QPixmapCache::clear();
140​
141​ setStyleRecursively(m_widget.data(), m_style.data());
142​
143​ m_widget->ensurePolished();
144​
145​ const auto sizeHint = m_widget->sizeHint();
146​ setImplicitSize(sizeHint.width(), sizeHint.height());
147​
148​ m_widget->resize(qRound(width()), qRound(height()));
149​
150​ m_widget->installEventFilter(this);
151​
152​ m_widget->show();
153​
154​ if (oldValid != isValid()) {
155​ emit validChanged();
156​ }
157​}
158​
159​void PreviewItem::paint(QPainter *painter)
160​{
161​ if (m_widget && m_widget->isVisible()) {
162​ m_widget->render(painter);
163​ }
164​}
165​
166​void PreviewItem::hoverMoveEvent(QHoverEvent *event)
167​{
168​ sendHoverEvent(event);
169​}
170​
171​void PreviewItem::hoverLeaveEvent(QHoverEvent *event)
172​{
173​ if (m_lastWidgetUnderMouse) {
174​ dispatchEnterLeave(nullptr, m_lastWidgetUnderMouse, mapToGlobal(event->pos()));
175​ m_lastWidgetUnderMouse = nullptr;
176​ }
177​}
178​
179​void PreviewItem::sendHoverEvent(QHoverEvent *event)
180​{
181​ if (!m_widget || !m_widget->isVisible()) {
182​ return;
183​ }
184​
185​ QPointF pos = event->pos();
186​
187​ QWidget *child = m_widget->childAt(pos.toPoint());
188​ QWidget *receiver = child ? child : m_widget.data();
189​
190​ dispatchEnterLeave(receiver, m_lastWidgetUnderMouse, mapToGlobal(event->pos()));
191​
192​ m_lastWidgetUnderMouse = receiver;
193​
194​ pos = receiver->mapFrom(m_widget.data(), pos.toPoint());
195​
196​ QMouseEvent mouseEvent(QEvent::MouseMove, pos, receiver->mapTo(receiver->topLevelWidget(), pos.toPoint()),
197​ receiver->mapToGlobal(pos.toPoint()),
198​ Qt::NoButton, {} /*buttons*/, event->modifiers());
199​
200​ qApp->sendEvent(receiver, &mouseEvent);
201​
202​ event->setAccepted(mouseEvent.isAccepted());
203​}
204​
205​// Simplified copy of QApplicationPrivate::dispatchEnterLeave
206​void PreviewItem::dispatchEnterLeave(QWidget *enter, QWidget *leave, const QPointF &globalPosF)
207​{
208​ if ((!enter && !leave) || (enter == leave)) {
209​ return;
210​ }
211​
212​ QWidgetList leaveList;
213​ QWidgetList enterList;
214​
215​ bool sameWindow = leave && enter && leave->window() == enter->window();
216​ if (leave && !sameWindow) {
217​ auto *w = leave;
218​ do {
219​ leaveList.append(w);
220​ } while (!w->isWindow() && (w = w->parentWidget()));
221​ }
222​ if (enter && !sameWindow) {
223​ auto *w = enter;
224​ do {
225​ enterList.append(w);
226​ } while (!w->isWindow() && (w = w->parentWidget()));
227​ }
228​ if (sameWindow) {
229​ int enterDepth = 0;
230​ int leaveDepth = 0;
231​ auto *e = enter;
232​ while (!e->isWindow() && (e = e->parentWidget()))
233​ enterDepth++;
234​ auto *l = leave;
235​ while (!l->isWindow() && (l = l->parentWidget()))
236​ leaveDepth++;
237​ QWidget* wenter = enter;
238​ QWidget* wleave = leave;
239​ while (enterDepth > leaveDepth) {
240​ wenter = wenter->parentWidget();
241​ enterDepth--;
242​ }
243​ while (leaveDepth > enterDepth) {
244​ wleave = wleave->parentWidget();
245​ leaveDepth--;
246​ }
247​ while (!wenter->isWindow() && wenter != wleave) {
248​ wenter = wenter->parentWidget();
249​ wleave = wleave->parentWidget();
250​ }
251​
252​ for (auto *w = leave; w != wleave; w = w->parentWidget())
253​ leaveList.append(w);
254​
255​ for (auto *w = enter; w != wenter; w = w->parentWidget())
256​ enterList.append(w);
257​ }
258​
259​ const QPoint globalPos = globalPosF.toPoint();
260​
261​ QEvent leaveEvent(QEvent::Leave);
262​ for (int i = 0; i < leaveList.size(); ++i) {
263​ auto *w = leaveList.at(i);
264​ QApplication::sendEvent(w, &leaveEvent);
265​ if (w->testAttribute(Qt::WA_Hover)) {
266​ QHoverEvent he(QEvent::HoverLeave, QPoint(-1, -1), w->mapFromGlobal(globalPos),
267​ QApplication::keyboardModifiers());
268​ QApplication::sendEvent(w, &he);
269​ }
270​ }
271​ if (!enterList.isEmpty()) {
272​ const QPoint windowPos = qAsConst(enterList).back()->window()->mapFromGlobal(globalPos);
273​ for (auto it = enterList.crbegin(), end = enterList.crend(); it != end; ++it) {
274​ auto *w = *it;
275​ const QPointF localPos = w->mapFromGlobal(globalPos);
276​ QEnterEvent enterEvent(localPos, windowPos, globalPosF);
277​ QApplication::sendEvent(w, &enterEvent);
278​ if (w->testAttribute(Qt::WA_Hover)) {
279​ QHoverEvent he(QEvent::HoverEnter, localPos, QPoint(-1, -1),
280​ QApplication::keyboardModifiers());
281​ QApplication::sendEvent(w, &he);
282​ }
283​ }
284​ }
285​}
286​
287​void PreviewItem::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
288​{
289​ if (!m_widget || newGeometry == oldGeometry) {
290​ return;
291​ }
292​
293​ m_widget->resize(qRound(newGeometry.width()), qRound(newGeometry.height()));
294​}
295​