Polish the StorageView example

Introduce nullptr and override. Change the ready/valid columns to
use check marks. Right-align the numerical columns. Add a shortcut
to refresh. Sort by path, making sure the root volume is first.

Task-number: QTBUG-60635
Change-Id: I74cda7647f544902aaf4d2a0ab76986f1523aa6f
Reviewed-by: Gatis Paeglis <gatis.paeglis@qt.io>

examples/widgets/itemviews/storageview/main.cpp

@@ -51,6 +51,7 @@
 
 #include <QtWidgets/QApplication>
 #include <QtWidgets/QHeaderView>
+#include <QtWidgets/QShortcut>
 #include <QtWidgets/QTreeView>
 
 #include "storagemodel.h"
@@ -60,9 +61,16 @@ int main(int argc, char *argv[])
     QApplication a(argc, argv);
 
     QTreeView view;
-    view.setModel(new StorageModel(&view));
     view.resize(640, 480);
+    view.setWindowTitle("Storage View");
     view.setSelectionBehavior(QAbstractItemView::SelectRows);
+
+    StorageModel *model = new StorageModel(&view);
+    model->refresh();
+    QShortcut *refreshShortcut = new QShortcut(Qt::CTRL + Qt::Key_R, &view);
+    QObject::connect(refreshShortcut, &QShortcut::activated, model, &StorageModel::refresh);
+    view.setModel(model);
+
     int columnCount = view.model()->columnCount();
     for (int c = 0; c < columnCount; ++c)
         view.resizeColumnToContents(c);

examples/widgets/itemviews/storageview/storagemodel.cpp

@@ -54,14 +54,27 @@
 #include <QDir>
 #include <QLocale>
 #include <qmath.h>
+#include <algorithm>
 #include <cmath>
 
 StorageModel::StorageModel(QObject *parent) :
-    QAbstractTableModel(parent),
-    m_volumes(QStorageInfo::mountedVolumes())
+    QAbstractTableModel(parent)
 {
 }
 
+void StorageModel::refresh()
+{
+    beginResetModel();
+    m_volumes = QStorageInfo::mountedVolumes();
+    std::sort(m_volumes.begin(), m_volumes.end(),
+              [](const QStorageInfo &st1, const QStorageInfo &st2) {
+                  static const QString rootSortString = QStringLiteral(" ");
+                  return (st1.isRoot() ? rootSortString : st1.rootPath())
+                       < (st2.isRoot() ? rootSortString : st2.rootPath());
+              });
+    endResetModel();
+}
+
 int StorageModel::columnCount(const QModelIndex &/*parent*/) const
 {
     return ColumnCount;
@@ -74,6 +87,22 @@ int StorageModel::rowCount(const QModelIndex &parent) const
     return m_volumes.count();
 }
 
+Qt::ItemFlags StorageModel::flags(const QModelIndex &index) const
+{
+    Qt::ItemFlags result = QAbstractTableModel::flags(index);
+    switch (index.column()) {
+    case ColumnAvailable:
+    case ColumnIsReady:
+    case ColumnIsReadOnly:
+    case ColumnIsValid:
+        result |= Qt::ItemIsUserCheckable;
+        break;
+    default:
+        break;
+    }
+    return result;
+}
+
 QVariant StorageModel::data(const QModelIndex &index, int role) const
 {
     if (!index.isValid())
@@ -96,6 +125,12 @@ QVariant StorageModel::data(const QModelIndex &index, int role) const
             return QLocale().formattedDataSize(volume.bytesFree());
         case ColumnAvailable:
             return QLocale().formattedDataSize(volume.bytesAvailable());
+        default:
+            break;
+        }
+    } else if (role == Qt::CheckStateRole) {
+        const QStorageInfo &volume = m_volumes.at(index.row());
+        switch (index.column()) {
         case ColumnIsReady:
             return volume.isReady();
         case ColumnIsReadOnly:
@@ -105,6 +140,16 @@ QVariant StorageModel::data(const QModelIndex &index, int role) const
         default:
             break;
         }
+    } else if (role == Qt::TextAlignmentRole) {
+        switch (index.column()) {
+        case ColumnTotal:
+        case ColumnFree:
+        case ColumnAvailable:
+            return Qt::AlignTrailing;
+        default:
+            break;
+        }
+        return Qt::AlignLeading;
     } else if (role == Qt::ToolTipRole) {
         QLocale locale;
         const QStorageInfo &volume = m_volumes.at(index.row());
@@ -147,13 +192,13 @@ QVariant StorageModel::headerData(int section, Qt::Orientation orientation, int
 
     switch (section) {
     case ColumnRootPath:
-        return tr("Root path");
+        return tr("Root Path");
     case ColumnName:
         return tr("Volume Name");
     case ColumnDevice:
         return tr("Device");
     case ColumnFileSystemName:
-        return tr("File system");
+        return tr("File System");
     case ColumnTotal:
         return tr("Total");
     case ColumnFree:

examples/widgets/itemviews/storageview/storagemodel.h

@@ -74,13 +74,17 @@ public:
         ColumnCount
     };
 
-    explicit StorageModel(QObject *parent = 0);
+    explicit StorageModel(QObject *parent = nullptr);
 
-    int columnCount(const QModelIndex &parent) const;
-    int rowCount(const QModelIndex &parent) const;
+    int columnCount(const QModelIndex &parent) const override;
+    int rowCount(const QModelIndex &parent) const override;
 
-    QVariant data(const QModelIndex &index, int role) const;
-    QVariant headerData(int section, Qt::Orientation orientation, int role) const;
+    QVariant data(const QModelIndex &index, int role) const override;
+    Qt::ItemFlags flags(const QModelIndex &index) const override;
+    QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
+
+public slots:
+    void refresh();
 
 private:
     QList<QStorageInfo> m_volumes;