Initial commit

imageringlist.cpp

@@ -0,0 +1,162 @@
+#include "imageringlist.h"
+#include <QThreadPool>
+#include <QDir>
+
+using namespace std;
+
+const int DEFAULT_WIDTH = 3;
+
+class LoadRunable : public QRunnable
+{
+    QString m_file;
+    QObject *m_receiver;
+public:
+    LoadRunable(const QString &file, QObject *receiver) :
+        m_file(file),
+        m_receiver(receiver)
+    {
+    }
+    void run()
+    {
+        QImage img(m_file);
+        QMetaObject::invokeMethod(m_receiver, "imageLoaded", Qt::QueuedConnection, Q_ARG(QImage, img));
+    }
+};
+
+Image::Image(const QString name) :
+    m_loading(false),
+    m_released(true),
+    m_name(name)
+{
+}
+
+void Image::load()
+{
+    if(m_pixmap.isNull() && !m_loading)
+    {
+        m_loading = true;
+        m_released = false;
+        QThreadPool::globalInstance()->start(new LoadRunable(m_name, this));
+    }
+    if(!m_loading && !m_pixmap.isNull())
+        emit pixmapLoaded(this);
+}
+
+void Image::release()
+{
+    m_pixmap = QPixmap();
+    m_released = true;
+}
+
+QString Image::name() const
+{
+    return m_name;
+}
+
+QPixmap Image::pixmap() const
+{
+    return m_pixmap;
+}
+
+void Image::imageLoaded(QImage img)
+{
+    m_loading = false;
+    if(!m_released)
+    {
+        m_pixmap = QPixmap::fromImage(img);
+        emit pixmapLoaded(this);
+    }
+}
+
+ImageRingList::ImageRingList(QObject *parent) : QObject(parent)
+{
+}
+
+bool ImageRingList::setDir(const QString path)
+{
+    QDir dir(path);
+
+    if(dir.exists())
+    {
+        QStringList nameFilter;
+        nameFilter << "*.jpg" << "*.png";
+
+        QStringList list = dir.entryList(nameFilter, QDir::Files | QDir::Readable, QDir::Name);
+        QStringList absolutePaths;
+        foreach(const QString &file, list)
+        {
+            absolutePaths.append(dir.absoluteFilePath(file));
+        }
+        setFiles(absolutePaths);
+        return true;
+    }
+    return false;
+}
+
+void ImageRingList::setFiles(const QStringList files)
+{
+    m_images.clear();
+    foreach(const QString &file, files)
+    {
+        ImagePtr ptr = make_shared<Image>(file);
+        connect(ptr.get(), SIGNAL(pixmapLoaded(Image*)), this, SLOT(imageLoaded(Image*)));
+        m_images.append(ptr);
+    }
+
+    m_firstImage = m_currImage = m_lastImage = m_images.begin();
+    (*m_currImage)->load();
+
+    m_width = DEFAULT_WIDTH<m_images.size()/2 ? DEFAULT_WIDTH : m_images.size()/2;
+
+    for(int i=0; i<m_width; i++)
+    {
+        m_firstImage = decrement(m_firstImage);
+        (*m_firstImage)->load();
+        m_lastImage = increment(m_lastImage);
+        (*m_lastImage)->load();
+    }
+}
+
+void ImageRingList::increment()
+{
+    (*m_firstImage)->release();
+    m_firstImage = increment(m_firstImage);
+    m_currImage = increment(m_currImage);
+    (*m_currImage)->load();
+    m_lastImage = increment(m_lastImage);
+    (*m_lastImage)->load();
+}
+
+void ImageRingList::decrement()
+{
+    (*m_lastImage)->release();
+    m_firstImage = decrement(m_firstImage);
+    m_currImage = decrement(m_currImage);
+    (*m_currImage)->load();
+    m_lastImage = decrement(m_lastImage);
+    (*m_firstImage)->load();
+}
+
+QList<shared_ptr<Image>>::iterator ImageRingList::increment(QList<ImagePtr>::iterator iter)
+{
+    iter++;
+    if(iter == m_images.end())
+        iter = m_images.begin();
+    return iter;
+}
+
+QList<shared_ptr<Image>>::iterator ImageRingList::decrement(QList<ImagePtr>::iterator iter)
+{
+    if(iter == m_images.begin())
+        iter = m_images.end();
+    iter--;
+    return iter;
+}
+
+void ImageRingList::imageLoaded(Image *image)
+{
+    if(image->name() == (*m_currImage)->name())
+    {
+        emit pixmapLoaded(image->pixmap());
+    }
+}