Implement "hide empty input" option

Fixes #144

src/widgets/helper/splitinput.cpp

@@ -198,6 +198,11 @@ void SplitInput::clearSelection()
     this->textInput.setTextCursor(c);
 }
 
+QString SplitInput::getInputText() const
+{
+    return this->textInput.toPlainText();
+}
+
 void SplitInput::refreshTheme()
 {
     QPalette palette;
@@ -213,6 +218,8 @@ void SplitInput::editTextChanged()
 {
     QString text = this->textInput.toPlainText();
 
+    this->textChanged.invoke(text);
+
     text = text.trimmed();
     static QRegularExpression spaceRegex("\\s\\s+");
     text = text.replace(spaceRegex, " ");

src/widgets/helper/splitinput.hpp

@@ -26,6 +26,9 @@ public:
     SplitInput(Split *_chatWidget);
 
     void clearSelection();
+    QString getInputText() const;
+
+    pajlada::Signals::Signal<const QString &> textChanged;
 
 protected:
     virtual void paintEvent(QPaintEvent *) override;