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50
51
52#include <qqmlextensionplugin.h>
53
54#include <qqmlengine.h>
55#include <qquickimageprovider.h>
56#include <QImage>
57#include <QPainter>
58
59class ColorImageProvider : public QQuickImageProvider
60{
61public:
62 ColorImageProvider()
63 : QQuickImageProvider(QQuickImageProvider::Pixmap)
64 {
65 }
66
67 QPixmap requestPixmap(const QString &id, QSize *size, const QSize &requestedSize) override
68 {
69 int width = 100;
70 int height = 50;
71
72 if (size)
73 *size = QSize(width, height);
74 QPixmap pixmap(requestedSize.width() > 0 ? requestedSize.width() : width,
75 requestedSize.height() > 0 ? requestedSize.height() : height);
76 pixmap.fill(fillColor: QColor(id).rgba());
77
78 // write the color name
79 QPainter painter(&pixmap);
80 QFont f = painter.font();
81 f.setPixelSize(20);
82 painter.setFont(f);
83 painter.setPen(Qt::black);
84 if (requestedSize.isValid())
85 painter.scale(sx: requestedSize.width() / width, sy: requestedSize.height() / height);
86 painter.drawText(r: QRectF(0, 0, width, height), flags: Qt::AlignCenter, text: id);
87
88 return pixmap;
89 }
90};
91
92
93class ImageProviderExtensionPlugin : public QQmlEngineExtensionPlugin
94{
95 Q_OBJECT
96 Q_PLUGIN_METADATA(IID QQmlEngineExtensionInterface_iid)
97public:
98 void initializeEngine(QQmlEngine *engine, const char *uri) override
99 {
100 Q_UNUSED(uri);
101 engine->addImageProvider(id: "colors", new ColorImageProvider);
102 }
103};
104
105
106#include "imageprovider.moc"
107

source code of qtdeclarative/examples/quick/imageprovider/imageprovider.cpp