commit 6fcd6c90

Poul Sander · 2026-02-19 21:12
6fcd6c908ee22b0d4a20f8acffe090df2d57e716 patch · browse files
parent cec3b5da99dae3e0c95c31493e5e98458e97ef84

Try to load the images a little more dynamic. Does not really work at the moment as the current icon field just gives everything every time

Changed files

M	imagemodel.cpp before
M	imagemodel.h before
M	mainwindow.cpp before
M	mainwindow.h before
M	thumbnailworker.cpp before
M	thumbnailworker.h before

diff --git a/imagemodel.cpp b/imagemodel.cpp index b6fd272..5c58083 100644 --- a/imagemodel.cpp +++ b/imagemodel.cpp

@@ -10,20 +10,25 @@ ImageModel::ImageModel(QObject *parent)

{

m_threadPool.setMaxThreadCount(QThread::idealThreadCount());

- // Simple gray placeholder

m_placeholder = QPixmap(128, 128);

m_placeholder.fill(Qt::lightGray);

}

ImageModel::~ImageModel()

{

+ m_cancelFlag = true;

m_threadPool.waitForDone();

}

void ImageModel::setDirectory(const QString &path)

{

+ m_cancelFlag = true;

+ m_threadPool.waitForDone();

+ m_cancelFlag = false;

beginResetModel();

m_items.clear();

+ m_pendingRows.clear();

QDir dir(path);

QStringList filters;

@@ -37,24 +42,56 @@ void ImageModel::setDirectory(const QString &path)

const auto files = dir.entryInfoList();

- int row = 0;

for (const QFileInfo &file : files)

{

m_items.append({file.absoluteFilePath(), m_placeholder, false});

+ }

- // Create worker

- auto *worker = new ThumbnailWorker(file.absoluteFilePath(), row);

+ endResetModel();

- connect(worker, &ThumbnailWorker::finished,

- this, &ImageModel::thumbnailReady,

- Qt::QueuedConnection);

+void ImageModel::requestThumbnails(int firstRow, int lastRow)

+ if (m_items.isEmpty())

+ return;

- m_threadPool.start(worker);

+ firstRow = std::max(0, firstRow);

+ lastRow = std::min(lastRow, static_cast<int>(m_items.size()) - 1);

- row++;

+ for (int row = firstRow; row <= lastRow; ++row)

+ {

+ if (!m_items[row].loaded)

+ queueRow(row);

}

- endResetModel();

+ // Optional: preload nearby rows

+ int buffer = 20;

+ for (int row = firstRow - buffer; row < firstRow; ++row)

+ if (row >= 0 && !m_items[row].loaded)

+ queueRow(row);

+ for (int row = lastRow + 1; row <= lastRow + buffer; ++row)

+ if (row < m_items.size() && !m_items[row].loaded)

+ queueRow(row);

+void ImageModel::queueRow(int row)

+ if (m_pendingRows.contains(row))

+ return;

+ m_pendingRows.insert(row);

+ auto *worker = new ThumbnailWorker(

+ m_items[row].path,

+ row,

+ &m_cancelFlag);

+ connect(worker, &ThumbnailWorker::finished,

+ this, &ImageModel::thumbnailReady,

+ Qt::QueuedConnection);

+ m_threadPool.start(worker);

}

QString ImageModel::filePath(const QModelIndex &index) const

@@ -86,13 +123,17 @@ QVariant ImageModel::data(const QModelIndex &index, int role) const

return {};

}

-void ImageModel::thumbnailReady(int row, const QPixmap &pixmap)

+void ImageModel::thumbnailReady(int row, const QImage &image)

{

+ if (m_cancelFlag)

+ return;

if (row < 0 || row >= m_items.size())

return;

- m_items[row].thumbnail = pixmap;

+ m_items[row].thumbnail = QPixmap::fromImage(image);

m_items[row].loaded = true;

+ m_pendingRows.remove(row);

QModelIndex idx = index(row);

emit dataChanged(idx, idx, {Qt::DecorationRole});

diff --git a/imagemodel.h b/imagemodel.h index ab11e6d..c124ae6 100644 --- a/imagemodel.h +++ b/imagemodel.h

@@ -4,6 +4,8 @@

#include <QPixmap>

#include <QVector>

#include <QThreadPool>

+#include <QSet>

+#include <atomic>

class ThumbnailWorker;

@@ -18,10 +20,12 @@ public:

void setDirectory(const QString &path);

QString filePath(const QModelIndex &index) const;

+ void requestThumbnails(int firstRow, int lastRow);

int rowCount(const QModelIndex &parent = QModelIndex()) const override;

QVariant data(const QModelIndex &index, int role) const override;

- void thumbnailReady(int row, const QPixmap &pixmap);

+ void thumbnailReady(int row, const QImage &image);

private:

struct Item

@@ -31,7 +35,12 @@ private:

bool loaded = false;

};

+ void queueRow(int row);

QVector<Item> m_items;

QThreadPool m_threadPool;

QPixmap m_placeholder;

+ QSet<int> m_pendingRows;

+ std::atomic_bool m_cancelFlag{false};

};

diff --git a/mainwindow.cpp b/mainwindow.cpp index a724b32..fedb644 100644 --- a/mainwindow.cpp +++ b/mainwindow.cpp

@@ -9,6 +9,10 @@

#include <QDir>

#include <QImageReader>

#include <QHeaderView>

+#include <QScrollBar>

+#include <QTimer>

+#include <QEvent>

+#include <iostream>

MainWindow::MainWindow(QWidget *parent)

: QMainWindow(parent)

@@ -67,24 +71,59 @@ void MainWindow::setupConnections()

{

connect(m_treeView, &QTreeView::clicked, this,

[this](const QModelIndex &index)

- {

- QString path = m_dirModel->filePath(index);

- m_imageModel->setDirectory(path);

- });

+ {

+ QString path = m_dirModel->filePath(index);

+ m_imageModel->setDirectory(path);

+ // Defer thumbnail load so the view has time to lay out items

+ QTimer::singleShot(0, this, &MainWindow::loadVisibleThumbnails);

+ });

connect(m_listView, &QListView::clicked, this,

[this](const QModelIndex &index)

- {

- QString path = m_imageModel->filePath(index);

- QImageReader reader(path);

- reader.setAutoTransform(true);

- QImage image = reader.read();

- m_previewLabel->setPixmap(

- QPixmap::fromImage(image).scaled(

- m_previewLabel->size(),

- Qt::KeepAspectRatio,

- Qt::SmoothTransformation));

- });

+ {

+ QString path = m_imageModel->filePath(index);

+ QImageReader reader(path);

+ reader.setAutoTransform(true);

+ QImage image = reader.read();

+ m_previewLabel->setPixmap(

+ QPixmap::fromImage(image).scaled(

+ m_previewLabel->size(),

+ Qt::KeepAspectRatio,

+ Qt::SmoothTransformation));

+ });

+ connect(m_listView->verticalScrollBar(), &QScrollBar::valueChanged,

+ this, [this]()

+ { loadVisibleThumbnails(); });

+ // Also catch resize — visible range changes when the viewport is resized

+ m_listView->viewport()->installEventFilter(this);

+bool MainWindow::eventFilter(QObject *obj, QEvent *event)

+ if (obj == m_listView->viewport() && event->type() == QEvent::Resize)

+ QTimer::singleShot(0, this, &MainWindow::loadVisibleThumbnails);

+ return QMainWindow::eventFilter(obj, event);

+void MainWindow::loadVisibleThumbnails()

+ QModelIndex topLeft = m_listView->indexAt(QPoint(0, 0));

+ QModelIndex bottomRight = m_listView->indexAt(

+ QPoint(m_listView->viewport()->width() - 1,

+ m_listView->viewport()->height() - 1));

+ int first = topLeft.isValid() ? topLeft.row() : 0;

+ int last = bottomRight.isValid() ? bottomRight.row()

+ : m_imageModel->rowCount() - 1;

+ if (last < 0)

+ return;

+ std::cout << "loadVisibleThumbnails: " << first << " - " << last << "\n";

+ m_imageModel->requestThumbnails(first, last);

}

diff --git a/mainwindow.h b/mainwindow.h index 43ecfe2..f801f66 100644 --- a/mainwindow.h +++ b/mainwindow.h

@@ -18,6 +18,9 @@ public:

private:

void setupUi();

void setupConnections();

+ void loadVisibleThumbnails();

+ bool eventFilter(QObject *obj, QEvent *event) override;

QFileSystemModel *m_dirModel;

ImageModel *m_imageModel;

diff --git a/thumbnailworker.cpp b/thumbnailworker.cpp index f02d710..25152d5 100644 --- a/thumbnailworker.cpp +++ b/thumbnailworker.cpp

@@ -1,27 +1,34 @@

#include "thumbnailworker.h"

#include <QImageReader>

-ThumbnailWorker::ThumbnailWorker(const QString &path, int row)

- : m_path(path), m_row(row)

+ThumbnailWorker::ThumbnailWorker(const QString &path,

+ int row,

+ std::atomic_bool *cancelFlag)

+ : m_path(path),

+ m_row(row),

+ m_cancelFlag(cancelFlag)

{

setAutoDelete(true);

}

void ThumbnailWorker::run()

{

+ if (*m_cancelFlag)

+ return;

QImageReader reader(m_path);

reader.setAutoTransform(true);

QImage image = reader.read();

- QPixmap thumb;

+ if (*m_cancelFlag)

+ return;

if (!image.isNull())

{

- thumb = QPixmap::fromImage(

- image.scaled(128, 128,

- Qt::KeepAspectRatio,

- Qt::SmoothTransformation));

+ QImage thumb = image.scaled(128, 128,

+ Qt::KeepAspectRatio,

+ Qt::SmoothTransformation);

+ emit finished(m_row, thumb);

}

- emit finished(m_row, thumb);

}

diff --git a/thumbnailworker.h b/thumbnailworker.h index 13df897..5cdb7cd 100644 --- a/thumbnailworker.h +++ b/thumbnailworker.h

@@ -2,21 +2,25 @@

#include <QRunnable>

#include <QObject>

-#include <QPixmap>

+#include <QImage>

+#include <atomic>

class ThumbnailWorker : public QObject, public QRunnable

{

Q_OBJECT

public:

- ThumbnailWorker(const QString &path, int row);

+ ThumbnailWorker(const QString &path,

+ int row,

+ std::atomic_bool *cancelFlag);

void run() override;

signals:

- void finished(int row, const QPixmap &pixmap);

+ void finished(int row, const QImage &image);

private:

QString m_path;

int m_row;

+ std::atomic_bool *m_cancelFlag;

};