Initial commit

Lts/Common/LtsWidgets/lts_combo_box.cpp

@@ -0,0 +1,125 @@
+/**
+ * @RDE_HEADER@
+ * ComboBox, optimized for tablets (bigger dropdown/popup and more comfortable completer)
+ * $Id$
+ * $HeadURL$
+ * $Author$
+ *
+ * Created by Mike Wille, SLSE, 2016-03-09
+ */
+
+#include "lts_combo_box.h"
+#include "lts_selection_popup.h"
+#include "lts_message_dialog.h"
+
+#include <QGuiApplication>
+#include <QShowEvent>
+
+//#define NEVER
+#ifdef NEVER
+#  include <QDebug>
+#endif // NEVER
+
+namespace LtsWidgets
+{
+
+bool LtsComboBox::s_useSelectionDialog = false;
+
+LtsComboBox::LtsComboBox(QWidget *parent)
+  : QComboBox(parent)
+  , m_currentIndex(-1)
+{
+  connect(this, &LtsComboBox::signalExternallyChanged,
+          this, &LtsComboBox::signalRefill); // sig on sig (to fetch cbx as sender)
+}
+
+void LtsComboBox::setUseSelectionDialog(bool bUseSelectionDialog)
+{
+  s_useSelectionDialog = bUseSelectionDialog;
+}
+
+void LtsComboBox::showEvent(QShowEvent *e)
+{
+  QComboBox::showEvent(e);
+
+  m_currentIndex = currentIndex();
+}
+
+void LtsComboBox::enterEvent(QEvent *e)
+{
+  BaseClass::enterEvent(e);
+  emit signalEnterEvent();
+}
+
+void LtsComboBox::leaveEvent(QEvent *e)
+{
+  BaseClass::leaveEvent(e);
+  emit signalLeaveEvent();
+}
+
+void LtsComboBox::showPopup()
+{
+  bool bUseSelectionDialog = s_useSelectionDialog;
+  if (QGuiApplication::queryKeyboardModifiers() == Qt::ControlModifier)
+    bUseSelectionDialog = !bUseSelectionDialog;
+  if (!bUseSelectionDialog)
+  {
+    QComboBox::showPopup(); // show original popup when CTRL is pressed
+    return;
+  }
+
+  if (!model()->rowCount()) // nothing to show? tell the user.
+  {
+    LtsWidgets::LtsMessageDialog::showMessage(this, tr("There are no items available!"));
+    return;
+  }
+
+  // create the touch-friendly, screen-centered custom popup and show it
+  LtsSelectionPopup* popup = new LtsSelectionPopup(model(), currentIndex(), this);
+  popup->setAttribute(Qt::WA_DeleteOnClose); // dialog must delete itself, as there is no  Dialog Helper
+
+#ifdef NEVER
+  // debugging :
+  //  // highlighted -> UserInteraction
+//  connect(popup, static_cast<void (LtsSelectionPopup::*)(int)>(&LtsSelectionPopup::highlighted), this, [](int idx){
+//    qCritical() << " LtsComboBox: called: highlighted(int), idx=" << idx;
+//  });
+
+  // currentIndexChanged -> programmatically & UserInteraction
+  connect(popup, static_cast<void (LtsSelectionPopup::*)(int)>(&LtsSelectionPopup::currentIndexChanged), this, [](int idx){
+    qCritical() << " LtsComboBox: called: currentIndexChanged(int), idx=" << idx;
+  });
+
+  // activated -> UserInteraction
+  connect(popup, static_cast<void (LtsSelectionPopup::*)(int)>(&LtsSelectionPopup::activated), this, [](int idx){
+    qCritical() << " LtsComboBox: called: activated(int), idx=" << idx;
+  });
+  // : debugging
+#endif // NEVER
+
+  // Although we derive from QComboBox, there seems to be no signal emitted implicitly.
+  // Therefore we have to listen to our popup:
+  connect(popup, &LtsSelectionPopup::currentIndexChanged,
+          this, &LtsComboBox::userChangedIndex);                                   // listen on changes
+  connect(popup, &LtsSelectionPopup::activated,
+          this, static_cast<void (LtsComboBox::*)(int)>(&LtsComboBox::activated)); // SIGNAL on SIGNAL !
+
+  popup->show();
+}
+
+
+void LtsComboBox::userChangedIndex(int index)
+{
+  m_currentIndex = index;
+  setCurrentIndex(index);
+}
+
+
+bool LtsComboBox::hasValueChanged() const
+{
+  if (m_currentIndex == -1)
+    return false;
+  return !(currentIndex() == m_currentIndex);
+}
+
+} // namespace LtsWidgets