feat: add prev and next button

README.md

@@ -23,6 +23,7 @@ Feel free to open up an issue to request an new language to translate.
 
  - Mixed `CR LF` and `LF`.
  - Ugly action icons.
+ - Ugly implementations.
  - For windows build, win32 APIs are used.
  - No drag-window-border-to-resize support under non-windows platforms (I use <kbd>Meta+Drag</kbd> to resize window under my x11 desktop).
 

graphicsview.cpp

@@ -242,7 +242,7 @@ void GraphicsView::dropEvent(QDropEvent *event)
         if (urls.isEmpty()) {
             showText(tr("File url list is empty"));
         } else {
-            showFileFromUrl(urls.first());
+            showFileFromUrl(urls.first(), true);
         }
     } else if (mimeData->hasImage()) {
         QImage img = qvariant_cast<QImage>(mimeData->imageData());

mainwindow.cpp

@@ -31,6 +31,7 @@ MainWindow::MainWindow(QWidget *parent) :
     this->setAttribute(Qt::WA_TranslucentBackground, true);
     this->setMinimumSize(710, 530);
     this->setWindowIcon(QIcon(":/icons/app-icon.svg"));
+    this->setMouseTracking(true);
 
     m_fadeOutAnimation = new QPropertyAnimation(this, "windowOpacity");
     m_fadeOutAnimation->setDuration(300);
@@ -72,13 +73,29 @@ MainWindow::MainWindow(QWidget *parent) :
     connect(m_graphicsView, &GraphicsView::requestGallery,
             this, &MainWindow::loadGalleryBySingleLocalFile);
 
-    m_closeButton = new ToolButton(m_graphicsView);
+    m_closeButton = new ToolButton(true, m_graphicsView);
     m_closeButton->setIcon(QIcon(":/icons/window-close"));
     m_closeButton->setIconSize(QSize(50, 50));
 
     connect(m_closeButton, &QAbstractButton::clicked,
             this, &MainWindow::closeWindow);
 
+    m_prevButton = new ToolButton(false, m_graphicsView);
+    m_prevButton->setIcon(QIcon(":/icons/go-previous"));
+    m_prevButton->setIconSize(QSize(75, 75));
+    m_prevButton->setVisible(false);
+    m_prevButton->setOpacity(0, false);
+    m_nextButton = new ToolButton(false, m_graphicsView);
+    m_nextButton->setIcon(QIcon(":/icons/go-next"));
+    m_nextButton->setIconSize(QSize(75, 75));
+    m_nextButton->setVisible(false);
+    m_nextButton->setOpacity(0, false);
+
+    connect(m_prevButton, &QAbstractButton::clicked,
+            this, &MainWindow::galleryPrev);
+    connect(m_nextButton, &QAbstractButton::clicked,
+            this, &MainWindow::galleryNext);
+
     m_bottomButtonGroup = new BottomButtonGroup(this);
 
     connect(m_bottomButtonGroup, &BottomButtonGroup::resetToOriginalBtnClicked,
@@ -109,6 +126,11 @@ MainWindow::MainWindow(QWidget *parent) :
     m_gv->setOpacity(0, false);
     m_closeButton->setOpacity(0, false);
 
+    connect(this, &MainWindow::galleryLoaded, this, [this]() {
+        m_prevButton->setVisible(isGalleryAvailable());
+        m_nextButton->setVisible(isGalleryAvailable());
+    });
+
     QShortcut * quitAppShorucut = new QShortcut(QKeySequence(Qt::Key_Space), this);
     connect(quitAppShorucut, &QShortcut::activated,
             std::bind(&MainWindow::quitAppAction, this, false));
@@ -222,13 +244,13 @@ void MainWindow::loadGalleryBySingleLocalFile(const QString &path)
         }
     }
 
-//    qDebug() << m_files << m_currentFileIndex;
+    emit galleryLoaded();
 }
 
 void MainWindow::galleryPrev()
 {
     int count = m_files.count();
-    if (m_currentFileIndex < 0 || m_files.isEmpty() || m_currentFileIndex >= m_files.count()) {
+    if (!isGalleryAvailable()) {
         return;
     }
 
@@ -240,7 +262,7 @@ void MainWindow::galleryPrev()
 void MainWindow::galleryNext()
 {
     int count = m_files.count();
-    if (m_currentFileIndex < 0 || m_files.isEmpty() || m_currentFileIndex >= m_files.count()) {
+    if (!isGalleryAvailable()) {
         return;
     }
 
@@ -249,6 +271,14 @@ void MainWindow::galleryNext()
     m_graphicsView->showFileFromUrl(m_files.at(m_currentFileIndex), false);
 }
 
+bool MainWindow::isGalleryAvailable()
+{
+    if (m_currentFileIndex < 0 || m_files.isEmpty() || m_currentFileIndex >= m_files.count()) {
+        return false;
+    }
+    return true;
+}
+
 void MainWindow::showEvent(QShowEvent *event)
 {
     updateWidgetsPosition();
@@ -262,6 +292,8 @@ void MainWindow::enterEvent(QEvent *event)
     m_gv->setOpacity(1);
 
     m_closeButton->setOpacity(1);
+    m_prevButton->setOpacity(1);
+    m_nextButton->setOpacity(1);
 
     return QMainWindow::enterEvent(event);
 }
@@ -272,6 +304,8 @@ void MainWindow::leaveEvent(QEvent *event)
     m_gv->setOpacity(0);
 
     m_closeButton->setOpacity(0);
+    m_prevButton->setOpacity(0);
+    m_nextButton->setOpacity(0);
 
     return QMainWindow::leaveEvent(event);
 }
@@ -537,6 +571,9 @@ void MainWindow::closeWindow()
 void MainWindow::updateWidgetsPosition()
 {
     m_closeButton->move(width() - m_closeButton->width(), 0);
+    m_prevButton->move(25, (height() - m_prevButton->height()) / 2);
+    m_nextButton->move(width() - m_nextButton->width() - 25,
+                       (height() - m_prevButton->height()) / 2);
     m_bottomButtonGroup->move((width() - m_bottomButtonGroup->width()) / 2,
                               height() - m_bottomButtonGroup->height());
     m_gv->move(width() - m_gv->width(), height() - m_gv->height());
@@ -546,6 +583,8 @@ void MainWindow::toggleProtectedMode()
 {
     m_protectedMode = !m_protectedMode;
     m_closeButton->setVisible(!m_protectedMode);
+    m_prevButton->setVisible(!m_protectedMode);
+    m_nextButton->setVisible(!m_protectedMode);
 }
 
 void MainWindow::toggleStayOnTop()

mainwindow.h

@@ -31,6 +31,10 @@ class MainWindow : public QMainWindow
     void loadGalleryBySingleLocalFile(const QString &path);
     void galleryPrev();
     void galleryNext();
+    bool isGalleryAvailable();
+
+signals:
+    void galleryLoaded();
 
 protected slots:
     void showEvent(QShowEvent *event) override;
@@ -61,6 +65,8 @@ protected slots:
     QPropertyAnimation *m_floatUpAnimation;
     QParallelAnimationGroup *m_exitAnimationGroup;
     ToolButton *m_closeButton;
+    ToolButton *m_prevButton;
+    ToolButton *m_nextButton;
     GraphicsView *m_graphicsView;
     NavigatorView *m_gv;
     BottomButtonGroup *m_bottomButtonGroup;

resources.qrc

@@ -8,5 +8,7 @@
         <file>icons/view-background-checkerboard.svg</file>
         <file>icons/app-icon.svg</file>
         <file>icons/window-close.svg</file>
+        <file>icons/go-next.svg</file>
+        <file>icons/go-previous.svg</file>
     </qresource>
 </RCC>

toolbutton.cpp

@@ -6,18 +6,20 @@
 #include <QGraphicsOpacityEffect>
 #include <QPropertyAnimation>
 
-ToolButton::ToolButton(QWidget *parent)
+ToolButton::ToolButton(bool hoverColor, QWidget *parent)
     : QPushButton(parent)
     , m_opacityHelper(new OpacityHelper(this))
 {
     setFlat(true);
-    setFixedSize(50, 50);
-    setStyleSheet("QPushButton {"
+    QString qss = "QPushButton {"
                   "background: transparent;"
-                  "}"
-                  "QPushButton:hover {"
-                  "background: red;"
-                  "}");
+                  "}";
+    if (hoverColor) {
+        qss += "QPushButton:hover {"
+               "background: red;"
+               "}";
+    }
+    setStyleSheet(qss);
 }
 
 void ToolButton::setOpacity(qreal opacity, bool animated)

toolbutton.h

@@ -8,7 +8,7 @@ class ToolButton : public QPushButton
 {
     Q_OBJECT
 public:
-    ToolButton(QWidget * parent = nullptr);
+    ToolButton(bool hoverColor = false, QWidget * parent = nullptr);
 
 public slots:
     void setOpacity(qreal opacity, bool animated = true);