pineapple-pictures/graphicsview.cpp

237 lines
6.5 KiB
C++

#include "graphicsview.h"
#include "graphicsscene.h"
#include <QDebug>
#include <QMouseEvent>
#include <QScrollBar>
#include <QMimeData>
#include <QImageReader>
GraphicsView::GraphicsView(QWidget *parent)
: QGraphicsView (parent)
{
setDragMode(QGraphicsView::ScrollHandDrag);
setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
setResizeAnchor(QGraphicsView::AnchorUnderMouse);
setStyleSheet("background-color: rgba(0, 0, 0, 220);"
"border-radius: 3px;");
setAcceptDrops(true);
setCheckerboardEnabled(false);
}
void GraphicsView::showFromUrlList(const QList<QUrl> &urlList)
{
if (urlList.isEmpty()) {
// yeah, it's possible. dragging QQ's original sticker will trigger this, for example.
showText("File url list is empty");
return;
}
QUrl url(urlList.first());
QString filePath(url.toLocalFile());
if (filePath.endsWith(".svg")) {
showSvg(filePath);
} else if (filePath.endsWith(".gif")) {
showGif(filePath);
} else {
QImageReader imageReader(filePath);
QImage::Format imageFormat = imageReader.imageFormat();
if (imageFormat == QImage::Format_Invalid) {
showText("File is not a valid image");
} else {
showImage(QPixmap::fromImageReader(&imageReader));
}
}
}
void GraphicsView::showImage(const QPixmap &pixmap)
{
resetTransform();
scene()->showImage(pixmap);
checkAndDoFitInView();
}
void GraphicsView::showText(const QString &text)
{
resetTransform();
scene()->showText(text);
checkAndDoFitInView();
}
void GraphicsView::showSvg(const QString &filepath)
{
resetTransform();
scene()->showSvg(filepath);
checkAndDoFitInView();
}
void GraphicsView::showGif(const QString &filepath)
{
resetTransform();
scene()->showGif(filepath);
checkAndDoFitInView();
}
GraphicsScene *GraphicsView::scene() const
{
return qobject_cast<GraphicsScene*>(QGraphicsView::scene());
}
void GraphicsView::setScene(GraphicsScene *scene)
{
return QGraphicsView::setScene(scene);
}
void GraphicsView::toggleCheckerboard()
{
setCheckerboardEnabled(!m_checkerboardEnabled);
}
void GraphicsView::mousePressEvent(QMouseEvent *event)
{
if (shouldIgnoreMousePressMoveEvent(event)) {
event->ignore();
// blumia: return here, or the QMouseEvent event transparency won't
// work if we set a QGraphicsView::ScrollHandDrag drag mode.
return;
}
return QGraphicsView::mousePressEvent(event);
}
void GraphicsView::mouseMoveEvent(QMouseEvent *event)
{
if (shouldIgnoreMousePressMoveEvent(event)) {
event->ignore();
}
return QGraphicsView::mouseMoveEvent(event);
}
void GraphicsView::mouseReleaseEvent(QMouseEvent *event)
{
QGraphicsItem *item = itemAt(event->pos());
if (!item) {
event->ignore();
}
return QGraphicsView::mouseReleaseEvent(event);
}
void GraphicsView::wheelEvent(QWheelEvent *event)
{
m_enableFitInView = false;
if (event->delta() > 0) {
scale(1.25, 1.25);
} else {
scale(0.8, 0.8);
}
}
void GraphicsView::resizeEvent(QResizeEvent *event)
{
if (m_enableFitInView) {
if (isThingSmallerThanWindowWith(QTransform()) && transform().m11() >= 1) {
// no longer need to do fitInView()
// but we leave the m_enableFitInView value unchanged in case
// user resize down the window again.
} else {
fitInView(sceneRect(), Qt::KeepAspectRatio);
}
}
return QGraphicsView::resizeEvent(event);
}
void GraphicsView::dragEnterEvent(QDragEnterEvent *event)
{
if (event->mimeData()->hasUrls() || event->mimeData()->hasImage() || event->mimeData()->hasText()) {
event->acceptProposedAction();
} else {
event->ignore();
}
qDebug() << event->mimeData() << "Drag Enter Event"
<< event->mimeData()->hasUrls() << event->mimeData()->hasImage()
<< event->mimeData()->formats() << event->mimeData()->hasFormat("text/uri-list");
return QGraphicsView::dragEnterEvent(event);
}
void GraphicsView::dragMoveEvent(QDragMoveEvent *event)
{
Q_UNUSED(event);
// by default, QGraphicsView/Scene will ignore the action if there are no QGraphicsItem under cursor.
// We actually doesn't care and would like to keep the drag event as-is, so just do nothing here.
}
void GraphicsView::dropEvent(QDropEvent *event)
{
event->acceptProposedAction();
const QMimeData * mimeData = event->mimeData();
if (mimeData->hasUrls()) {
showFromUrlList(mimeData->urls());
} else if (mimeData->hasImage()) {
QImage img = qvariant_cast<QImage>(mimeData->imageData());
QPixmap pixmap = QPixmap::fromImage(img);
if (pixmap.isNull()) {
showText("Image data is invalid");
} else {
showImage(pixmap);
}
} else if (mimeData->hasText()) {
showText(mimeData->text());
} else {
showText("Not supported mimedata: " + mimeData->formats().first());
}
}
bool GraphicsView::isThingSmallerThanWindowWith(const QTransform &transform) const
{
return rect().size().expandedTo(transform.mapRect(sceneRect()).size().toSize())
== rect().size();
}
bool GraphicsView::shouldIgnoreMousePressMoveEvent(const QMouseEvent *event) const
{
if (isThingSmallerThanWindowWith(transform())) {
return true;
}
QGraphicsItem *item = itemAt(event->pos());
if (!item) {
return true;
}
return false;
}
void GraphicsView::checkAndDoFitInView()
{
if (!isThingSmallerThanWindowWith(transform())) {
m_enableFitInView = true;
fitInView(sceneRect(), Qt::KeepAspectRatio);
}
}
void GraphicsView::setCheckerboardEnabled(bool enabled)
{
m_checkerboardEnabled = enabled;
if (m_checkerboardEnabled) {
// Prepare background check-board pattern
QPixmap tilePixmap(0x20, 0x20);
tilePixmap.fill(QColor(30, 30, 30, 100));
QPainter tilePainter(&tilePixmap);
QColor color(40, 40, 40, 100);
tilePainter.fillRect(0, 0, 0x10, 0x10, color);
tilePainter.fillRect(0x10, 0x10, 0x10, 0x10, color);
tilePainter.end();
setBackgroundBrush(tilePixmap);
} else {
setBackgroundBrush(Qt::transparent);
}
}