NOISSUE continue reshuffling the codebase

launcher/ui/widgets/VersionListView.cpp

@@ -0,0 +1,163 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <QHeaderView>
+#include <QApplication>
+#include <QMouseEvent>
+#include <QDrag>
+#include <QPainter>
+#include "VersionListView.h"
+#include "Common.h"
+
+VersionListView::VersionListView(QWidget *parent)
+    :QTreeView ( parent )
+{
+    m_emptyString = tr("No versions are currently available.");
+}
+
+void VersionListView::rowsInserted(const QModelIndex &parent, int start, int end)
+{
+    m_itemCount += end-start+1;
+    updateEmptyViewPort();
+    QTreeView::rowsInserted(parent, start, end);
+}
+
+
+void VersionListView::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
+{
+    m_itemCount -= end-start+1;
+    updateEmptyViewPort();
+    QTreeView::rowsInserted(parent, start, end);
+}
+
+void VersionListView::setModel(QAbstractItemModel *model)
+{
+    m_itemCount = model->rowCount();
+    updateEmptyViewPort();
+    QTreeView::setModel(model);
+}
+
+void VersionListView::reset()
+{
+    if(model())
+    {
+        m_itemCount = model()->rowCount();
+    }
+    else {
+        m_itemCount = 0;
+    }
+    updateEmptyViewPort();
+    QTreeView::reset();
+}
+
+void VersionListView::setEmptyString(QString emptyString)
+{
+    m_emptyString = emptyString;
+    updateEmptyViewPort();
+}
+
+void VersionListView::setEmptyErrorString(QString emptyErrorString)
+{
+    m_emptyErrorString = emptyErrorString;
+    updateEmptyViewPort();
+}
+
+void VersionListView::setEmptyMode(VersionListView::EmptyMode mode)
+{
+    m_emptyMode = mode;
+    updateEmptyViewPort();
+}
+
+void VersionListView::updateEmptyViewPort()
+{
+#ifndef QT_NO_ACCESSIBILITY
+    setAccessibleDescription(currentEmptyString());
+#endif /* !QT_NO_ACCESSIBILITY */
+
+    if(!m_itemCount)
+    {
+        viewport()->update();
+    }
+}
+
+void VersionListView::paintEvent(QPaintEvent *event)
+{
+    if(m_itemCount)
+    {
+        QTreeView::paintEvent(event);
+    }
+    else
+    {
+        paintInfoLabel(event);
+    }
+}
+
+QString VersionListView::currentEmptyString() const
+{
+    if(m_itemCount) {
+        return QString();
+    }
+    switch(m_emptyMode)
+    {
+        default:
+        case VersionListView::Empty:
+            return QString();
+        case VersionListView::String:
+            return m_emptyString;
+        case VersionListView::ErrorString:
+            return m_emptyErrorString;
+    }
+}
+
+
+void VersionListView::paintInfoLabel(QPaintEvent *event) const
+{
+    QString emptyString = currentEmptyString();
+
+    //calculate the rect for the overlay
+    QPainter painter(viewport());
+    painter.setRenderHint(QPainter::Antialiasing, true);
+    QFont font("sans", 20);
+    font.setBold(true);
+
+    QRect bounds = viewport()->geometry();
+    bounds.moveTop(0);
+    auto innerBounds = bounds;
+    innerBounds.adjust(10, 10, -10, -10);
+
+    QColor background = QApplication::palette().color(QPalette::Foreground);
+    QColor foreground = QApplication::palette().color(QPalette::Base);
+    foreground.setAlpha(190);
+    painter.setFont(font);
+    auto fontMetrics = painter.fontMetrics();
+    auto textRect = fontMetrics.boundingRect(innerBounds, Qt::AlignHCenter | Qt::TextWordWrap, emptyString);
+    textRect.moveCenter(bounds.center());
+
+    auto wrapRect = textRect;
+    wrapRect.adjust(-10, -10, 10, 10);
+
+    //check if we are allowed to draw in our area
+    if (!event->rect().intersects(wrapRect)) {
+        return;
+    }
+
+    painter.setBrush(QBrush(background));
+    painter.setPen(foreground);
+    painter.drawRoundedRect(wrapRect, 5.0, 5.0);
+
+    painter.setPen(foreground);
+    painter.setFont(font);
+    painter.drawText(textRect, Qt::AlignHCenter | Qt::TextWordWrap, emptyString);
+}