File: kled.cpp

package info (click to toggle)
kwidgetsaddons 5.28.0-3
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 62,388 kB
  • ctags: 3,611
  • sloc: cpp: 26,647; python: 682; sh: 23; makefile: 6
file content (283 lines) | stat: -rw-r--r-- 6,789 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
/* This file is part of the KDE libraries
    Copyright (C) 1998 Jörg Habenicht (j.habenicht@europemail.com)
    Copyright (C) 2010 Christoph Feck <cfeck@kde.org>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/

#include "kled.h"

#include <QApplication>
#include <QPainter>
#include <QImage>
#include <QStyle>
#include <QStyleOption>

class KLed::Private
{
public:
    Private()
        : darkFactor(300),
          state(On), look(Raised), shape(Circular)
    {
    }

    int darkFactor;
    QColor color;
    State state;
    Look look;
    Shape shape;

    QPixmap cachedPixmap[2]; // for both states
};

KLed::KLed(QWidget *parent)
    : QWidget(parent),
      d(new Private)
{
    setColor(Qt::green);
    updateAccessibleName();
}

KLed::KLed(const QColor &color, QWidget *parent)
    : QWidget(parent),
      d(new Private)
{
    setColor(color);
    updateAccessibleName();
}

KLed::KLed(const QColor &color, State state, Look look, Shape shape,
           QWidget *parent)
    : QWidget(parent),
      d(new Private)
{
    d->state = (state == Off ? Off : On);
    d->look = look;
    d->shape = shape;

    setColor(color);
    updateAccessibleName();
}

KLed::~KLed()
{
    delete d;
}

KLed::State KLed::state() const
{
    return d->state;
}

KLed::Shape KLed::shape() const
{
    return d->shape;
}

QColor KLed::color() const
{
    return d->color;
}

KLed::Look KLed::look() const
{
    return d->look;
}

void KLed::setState(State state)
{
    if (d->state == state) {
        return;
    }

    d->state = (state == Off ? Off : On);
    updateCachedPixmap();
    updateAccessibleName();
}

void KLed::setShape(Shape shape)
{
    if (d->shape == shape) {
        return;
    }

    d->shape = shape;
    updateCachedPixmap();
}

void KLed::setColor(const QColor &color)
{
    if (d->color == color) {
        return;
    }

    d->color = color;
    updateCachedPixmap();
}

void KLed::setDarkFactor(int darkFactor)
{
    if (d->darkFactor == darkFactor) {
        return;
    }

    d->darkFactor = darkFactor;
    updateCachedPixmap();
}

int KLed::darkFactor() const
{
    return d->darkFactor;
}

void KLed::setLook(Look look)
{
    if (d->look == look) {
        return;
    }

    d->look = look;
    updateCachedPixmap();
}

void KLed::toggle()
{
    d->state = (d->state == On ? Off : On);
    updateCachedPixmap();
    updateAccessibleName();
}

void KLed::on()
{
    setState(On);
}

void KLed::off()
{
    setState(Off);
}

void KLed::resizeEvent(QResizeEvent *)
{
    updateCachedPixmap();
}

QSize KLed::sizeHint() const
{
    QStyleOption option;
    option.initFrom(this);
    int iconSize = style()->pixelMetric(QStyle::PM_SmallIconSize, &option, this);
    return QSize(iconSize,  iconSize);
}

QSize KLed::minimumSizeHint() const
{
    return QSize(16, 16);
}

void KLed::updateAccessibleName()
{
#ifndef QT_NO_ACCESSIBILITY
    QString onName = tr("LED on", "Accessible name of a Led whose state is on");
    QString offName = tr("LED off", "Accessible name of a Led whose state is off");
    QString lastName = accessibleName();

    if (lastName.isEmpty() || lastName == onName || lastName == offName) {
        //Accessible name has not been manually set.

        setAccessibleName(d->state == On ? onName : offName);
    }
#endif
}

void KLed::updateCachedPixmap()
{
    d->cachedPixmap[Off] = QPixmap();
    d->cachedPixmap[On] = QPixmap();
    update();
}

void KLed::paintEvent(QPaintEvent *)
{
    if (!d->cachedPixmap[d->state].isNull()) {
        QPainter painter(this);
        painter.drawPixmap(1, 1, d->cachedPixmap[d->state]);
        return;
    }

    QSize size(width() - 2, height() - 2);
    if (d->shape == Circular) {
        // Make sure the LED is round
        const int dim = qMin(width(), height()) - 2;
        size = QSize(dim, dim);
    }
    QPointF center(size.width() / 2.0, size.height() / 2.0);
    const int smallestSize = qMin(size.width(), size.height());
    QPainter painter;

    QImage image(size, QImage::Format_ARGB32_Premultiplied);
    image.fill(0);

    QRadialGradient fillGradient(center, smallestSize / 2.0, QPointF(center.x(), size.height() / 3.0));
    const QColor fillColor = d->state != Off ? d->color : d->color.dark(d->darkFactor);
    fillGradient.setColorAt(0.0, fillColor.light(250));
    fillGradient.setColorAt(0.5, fillColor.light(130));
    fillGradient.setColorAt(1.0, fillColor);

    QConicalGradient borderGradient(center, d->look == Sunken ? 90 : -90);
    QColor borderColor = palette().color(QPalette::Dark);
    if (d->state == On) {
        QColor glowOverlay = fillColor;
        glowOverlay.setAlpha(80);

        // This isn't the fastest way, but should be "fast enough".
        // It's also the only safe way to use QPainter::CompositionMode
        QImage img(1, 1, QImage::Format_ARGB32_Premultiplied);
        QPainter p(&img);
        QColor start = borderColor;
        start.setAlpha(255); // opaque
        p.fillRect(0, 0, 1, 1, start);
        p.setCompositionMode(QPainter::CompositionMode_SourceOver);
        p.fillRect(0, 0, 1, 1, glowOverlay);
        p.end();

        borderColor = img.pixel(0, 0);
    }
    borderGradient.setColorAt(0.2, borderColor);
    borderGradient.setColorAt(0.5, palette().color(QPalette::Light));
    borderGradient.setColorAt(0.8, borderColor);

    painter.begin(&image);
    painter.setRenderHint(QPainter::Antialiasing);
    painter.setBrush(d->look == Flat ? QBrush(fillColor) : QBrush(fillGradient));
    const QBrush penBrush = (d->look == Flat) ? QBrush(borderColor) : QBrush(borderGradient);
    const qreal penWidth = smallestSize / 8.0;
    painter.setPen(QPen(penBrush, penWidth));
    QRectF r(penWidth / 2.0, penWidth / 2.0, size.width() - penWidth, size.height() - penWidth);
    if (d->shape == Rectangular) {
        painter.drawRect(r);
    } else {
        painter.drawEllipse(r);
    }
    painter.end();

    d->cachedPixmap[d->state] = QPixmap::fromImage(image);
    painter.begin(this);
    painter.drawPixmap(1, 1, d->cachedPixmap[d->state]);
    painter.end();
}