Using QDataWidgetMapper in ItemDetailMapper to work with the model data (current index of the TableView).

views/itemdetailmapper.cpp

@@ -1,14 +1,30 @@
 #include "itemdetailmapper.h"
 
+#include <QAbstractItemModel>
+#include <QDataWidgetMapper>
 #include <QGridLayout>
 #include <QJsonArray>
 #include <QJsonObject>
 #include <QLabel>
 #include <QLineEdit>
+#include <QPushButton>
 #include <QSpinBox>
+#include <QTableView>
 
 ItemDetailMapper::ItemDetailMapper(QWidget* parent)
     : QWidget{parent} {
+  /// model mapping
+  m_mapper = std::make_unique<QDataWidgetMapper>(this);
+  m_mapper->setSubmitPolicy(QDataWidgetMapper::ManualSubmit);
+
+  /// model mapping buttons
+  m_nextButton     = new QPushButton(tr("Ne&xt"));
+  m_previousButton = new QPushButton(tr("&Previous"));
+
+  connect(m_previousButton, &QAbstractButton::clicked, this, &ItemDetailMapper::toPrevious);
+  connect(m_nextButton, &QAbstractButton::clicked, this, &ItemDetailMapper::toNext);
+
+  /// the individual widgets
   // REFACTOR deduce label names and types from meta data & use a factory
   m_nameLabel = new QLabel("&Name");
   m_nameEdit  = new QLineEdit();
@@ -44,5 +60,83 @@ ItemDetailMapper::ItemDetailMapper(QWidget* parent)
   layout->addWidget(m_factorLabel, 4, 0, 1, 1);
   layout->addWidget(m_factorBox, 4, 1, 1, 1);
 
+  layout->addWidget(m_previousButton, 5, 0, 1, 1);
+  layout->addWidget(m_nextButton, 5, 1, 1, 1);
+
   setLayout(layout);
 }
+
+void ItemDetailMapper::setModelMappings(QTableView* tableView) {
+  qDebug() << "Setting model...";
+  m_tableView      = tableView;
+  m_model          = tableView->model();
+  m_selectionModel = tableView->selectionModel();
+
+  m_mapper->setModel(m_model);
+  m_mapper->addMapping(m_nameEdit, 0);
+  m_mapper->addMapping(m_descriptionEdit, 1);
+  m_mapper->addMapping(m_infoEdit, 2);
+  m_mapper->addMapping(m_amountBox, 3);
+  m_mapper->addMapping(m_factorBox, 4);
+
+  m_mapper->setCurrentIndex(m_selectionModel->currentIndex().row());
+
+  connect(m_model, &QAbstractItemModel::rowsInserted, this, &ItemDetailMapper::rowsInserted);
+  connect(m_model, &QAbstractItemModel::rowsRemoved, this, &ItemDetailMapper::rowsRemoved);
+  connect(m_selectionModel, &QItemSelectionModel::currentChanged, this,
+          &ItemDetailMapper::onCurrentIndexChanged);
+
+  updateButtons(m_selectionModel->currentIndex().row());
+}
+
+bool ItemDetailMapper::submit() { return m_mapper->submit(); }
+
+void ItemDetailMapper::revert() { m_mapper->revert(); }
+
+void ItemDetailMapper::onCurrentIndexChanged(const QModelIndex& current,
+                                             const QModelIndex& previous) {
+  if (!isEnabled()) {
+    setEnabled(true);
+  }
+  m_mapper->setCurrentModelIndex(current);
+  updateButtons(current.row());
+}
+
+void ItemDetailMapper::rowsInserted(const QModelIndex& parent, int start, int end) {
+  updateButtons(m_mapper->currentIndex());
+}
+
+void ItemDetailMapper::rowsRemoved(const QModelIndex& parent, int start, int end) {
+  if (m_model->rowCount() == 0) {
+    setEnabled(false);
+
+    m_nameEdit->clear();
+    m_descriptionEdit->clear();
+    m_infoEdit->clear();
+    m_amountBox->clear();
+    m_factorBox->clear();
+  }
+
+  updateButtons(m_mapper->currentIndex());
+}
+
+void ItemDetailMapper::toPrevious() {
+  int currentRow            = m_selectionModel->currentIndex().row();
+  QModelIndex previousIndex = m_selectionModel->currentIndex().siblingAtRow(currentRow - 1);
+  if (previousIndex.isValid()) {
+    m_selectionModel->setCurrentIndex(previousIndex, QItemSelectionModel::ClearAndSelect);
+  }
+}
+
+void ItemDetailMapper::toNext() {
+  int currentRow        = m_selectionModel->currentIndex().row();
+  QModelIndex nextIndex = m_selectionModel->currentIndex().siblingAtRow(currentRow + 1);
+  if (nextIndex.isValid()) {
+    m_selectionModel->setCurrentIndex(nextIndex, QItemSelectionModel::ClearAndSelect);
+  }
+}
+
+void ItemDetailMapper::updateButtons(int row) {
+  m_previousButton->setEnabled(row > 0);
+  m_nextButton->setEnabled(row < m_model->rowCount() - 1);
+}