[Qt] Add sorting feature to the requested payments table

Author: cozz

src/qt/forms/receivecoinsdialog.ui

@@ -207,7 +207,11 @@
        </widget>
       </item>
       <item>
-       <widget class="QTableView" name="recentRequestsView"/>
+       <widget class="QTableView" name="recentRequestsView">
+        <property name="sortingEnabled">
+         <bool>true</bool>
+        </property>
+       </widget>
       </item>
       <item>
        <layout class="QHBoxLayout" name="horizontalLayout_2">

src/qt/receivecoinsdialog.cpp

@@ -55,6 +55,8 @@ void ReceiveCoinsDialog::setModel(WalletModel *model)
         ui->recentRequestsView->horizontalHeader()->setSectionResizeMode(RecentRequestsTableModel::Message, QHeaderView::Stretch);
 #endif
         ui->recentRequestsView->horizontalHeader()->resizeSection(RecentRequestsTableModel::Amount, 100);
+
+        model->getRecentRequestsTableModel()->sort(RecentRequestsTableModel::Date, Qt::DescendingOrder);
     }
 }
 

src/qt/recentrequeststablemodel.cpp

@@ -175,3 +175,31 @@ void RecentRequestsTableModel::addNewRequest(RecentRequestEntry &recipient)
     list.prepend(recipient);
     endInsertRows();
 }
+
+void RecentRequestsTableModel::sort(int column, Qt::SortOrder order)
+{
+    qSort(list.begin(), list.end(), RecentRequestEntryLessThan(column, order));
+    emit dataChanged(index(0, 0, QModelIndex()), index(list.size() - 1, NUMBER_OF_COLUMNS - 1, QModelIndex()));
+}
+
+bool RecentRequestEntryLessThan::operator()(RecentRequestEntry &left, RecentRequestEntry &right) const
+{
+    RecentRequestEntry *pLeft = &left;
+    RecentRequestEntry *pRight = &right;
+    if (order == Qt::DescendingOrder)
+        std::swap(pLeft, pRight);
+
+    switch(column)
+    {
+    case RecentRequestsTableModel::Date:
+        return pLeft->date.toTime_t() < pRight->date.toTime_t();
+    case RecentRequestsTableModel::Label:
+        return pLeft->recipient.label < pRight->recipient.label;
+    case RecentRequestsTableModel::Message:
+        return pLeft->recipient.message < pRight->recipient.message;
+    case RecentRequestsTableModel::Amount:
+        return pLeft->recipient.amount < pRight->recipient.amount;
+    default:
+        return pLeft->id < pRight->id;
+    }
+}

src/qt/recentrequeststablemodel.h

@@ -41,6 +41,18 @@ class RecentRequestEntry
     )
 };
 
+class RecentRequestEntryLessThan
+{
+public:
+    RecentRequestEntryLessThan(int nColumn, Qt::SortOrder fOrder):
+        column(nColumn), order(fOrder) {}
+    bool operator()(RecentRequestEntry &left, RecentRequestEntry &right ) const;
+
+private:
+    int column;
+    Qt::SortOrder order;
+};
+
 /** Model for list of recently generated payment requests / bitcoin URIs.
  * Part of wallet model.
  */
@@ -56,7 +68,8 @@ class RecentRequestsTableModel: public QAbstractTableModel
         Date = 0,
         Label = 1,
         Message = 2,
-        Amount = 3
+        Amount = 3,
+        NUMBER_OF_COLUMNS
     };
 
     /** @name Methods overridden from QAbstractTableModel
@@ -76,6 +89,9 @@ class RecentRequestsTableModel: public QAbstractTableModel
     void addNewRequest(const std::string &recipient);
     void addNewRequest(RecentRequestEntry &recipient);
 
+public slots:
+    void sort(int column, Qt::SortOrder order = Qt::AscendingOrder);
+
 private:
     WalletModel *walletModel;
     QStringList columns;