Allow +/- to toggle rather than insert.

radixwidgets/numberpadwidget.cc

@@ -42,9 +42,10 @@ QString keyToCharacter(int key)
   return QString();
 }
 
-NumberPadWidget::NumberPadWidget(QWidget *parent)
+NumberPadWidget::NumberPadWidget(QWidget *parent, bool toggle)
     : QLineEdit(parent)
 {
+  mToggle = toggle;
   mMapper = new QSignalMapper(this);
   connect(mMapper, SIGNAL(mapped(int)), SLOT(buttonClicked(int)));
 
@@ -90,8 +91,17 @@ NumberPadWidget::NumberPadWidget(QWidget *parent)
     }
 
     button->setText(QString::fromLatin1(keyboardLayout[i].label));
-    mMapper->setMapping(button, keyboardLayout[i].key);
-    connect(button, SIGNAL(clicked()), mMapper, SLOT(map()));
+
+    if (mToggle && keyboardLayout[i].key == Qt::Key_Plus)
+      connect(button, SIGNAL(clicked()), this, SLOT(makePositive()));
+    else if (mToggle && keyboardLayout[i].key == Qt::Key_Minus)
+      connect(button, SIGNAL(clicked()), this, SLOT(makeNegative()));
+    else
+    {
+      mMapper->setMapping(button, keyboardLayout[i].key);
+      connect(button, SIGNAL(clicked()), mMapper, SLOT(map()));
+    }
+
     mNumLayout->addWidget(button, row, col, 1, colSpan);
     col++;
   }
@@ -103,6 +113,24 @@ void NumberPadWidget::buttonClicked(int key)
   QLineEdit::keyPressEvent(&event);
 }
 
+void NumberPadWidget::makePositive()
+{
+  QString sval = text().trimmed();
+  if (sval.startsWith("-"))
+  {
+    setText(sval.mid(1));
+  }
+}
+
+void NumberPadWidget::makeNegative()
+{
+  QString sval = text().trimmed();
+  if (!sval.startsWith("-"))
+  {
+    setText(sval.prepend("-"));
+  }
+}
+
 void NumberPadWidget::focusInEvent(QFocusEvent *event)
 {
   QLineEdit::focusInEvent(event);

radixwidgets/numberpadwidget.hh

@@ -17,9 +17,10 @@ class RADIX_PUBLIC NumberPadWidget : public QLineEdit
   QSignalMapper* mMapper;
   QWidget* mNumberWidget;
   QGridLayout* mNumLayout;
+  bool mToggle;
 
  public:
-  NumberPadWidget(QWidget* parent = nullptr);
+  NumberPadWidget(QWidget* parent = nullptr, bool toggle = false);
 
  public slots:
   void focusInEvent(QFocusEvent*) override;
@@ -28,6 +29,8 @@ class RADIX_PUBLIC NumberPadWidget : public QLineEdit
 
  private slots:
   void buttonClicked(int key);
+  void makePositive();
+  void makeNegative();
 };  // class
 }  // namespace radix
 #endif /** RADIX_RADIXWIDGETS_NUMBERPADWIDGET_HH_ */