How to change QGraphicsView background color based on specific QString content inside a QListView

In order to shrink the problem I made a small verifiable example of a small gui. If you would like to take a glance at the code you can see it here.

I have a specific string on a QLineEdit, this string is passed to a QListView via QPushButton as shown below. Those strings are choices of a QComboBox and they are very specific: 1) "[ INFO] Minimum Distance: 5", 2) "[ INFO] Minimum Distance: 10" and 3) "[ INFO] Minimum Distance: 15"

The problem: How can I detect the specific QString content inside a QListView in order to change the background color of a QGraphicsView?

For example if inside the QListView there is "[ INFO] Minimum Distance: 5", the color of the QGraphicsView should be red or if inside the QListView there is "[ INFO] Minimum Distance: 10", the color of the QGraphicsView should be yellow etc.

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    mView = new QGraphicsView();
    mScene = new QGraphicsScene();
    ui->graphicsView->setScene(mScene);

    mText = new QGraphicsTextItem;
    mText->setPos(150,70);
    mScene->addText(tr("Boat outside alarm area"))->setDefaultTextColor(Qt::black);

    model = new QStringListModel();
    ui->listView->setModel(model);
    ui->listView->setEditTriggers(QAbstractItemView::NoEditTriggers);

    changeColorDetection();

}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::changeColorDetection()
{
    QColor red;
    QColor yellow;
    QColor green;

    // if [ INFO] Minimum Distance: 5 inside QListView
    // Than change color of the QGraphicsView background to red

    // if [ INFO] Minimum Distance: 10 inside QListView
    // Than change color of the QGraphicsView background to yellow

    QModelIndex index = ui->listView->currentIndex();
    QString itemText = index.data(Qt::DisplayRole).toString();
    if(itemText.startsWith("[ INFO] Minimum Distance: 10"))
    {
        ui->graphicsView->setStyleSheet("QGraphicsView {background-color: red}");
    }
}

void MainWindow::on_pushButton_clicked()
{
    QString str = ui->lineEdit->text();
    model->insertRow(model->rowCount());
    QModelIndex index = model->index(model->rowCount()-1);
    model->setData(index, str);
}


void MainWindow::on_comboBox_currentIndexChanged(const QString &arg1)
{
    QString list = ui->comboBox->currentText();
    ui->lineEdit->setText(list);
    Q_UNUSED(arg1)
}

mainwindow.h

#include <QGraphicsView>
#include <QGraphicsScene>
#include <QGraphicsTextItem>
#include <QStringListModel>

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
    void changeColorDetection();

private slots:
    void on_pushButton_clicked();
    void on_comboBox_currentIndexChanged(const QString &arg1);

private:
    Ui::MainWindow *ui;
    QGraphicsView *mView;
    QGraphicsScene *mScene;
    QGraphicsTextItem *mText;
    QStringListModel *model;

};
#endif // MAINWINDOW_H

main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    return a.exec();
}

In case you also would like to see the small .ui the code is below:

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>555</width>
    <height>382</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QGridLayout" name="gridLayout_2">
    <item row="0" column="0">
     <layout class="QVBoxLayout" name="verticalLayout">
      <item>
       <widget class="QGroupBox" name="groupBox">
        <property name="title">
         <string>Area</string>
        </property>
        <layout class="QGridLayout" name="gridLayout">
         <item row="0" column="0">
          <layout class="QHBoxLayout" name="horizontalLayout">
           <item>
            <widget class="QCheckBox" name="checkBoxRedArea">
             <property name="text">
              <string>Red area</string>
             </property>
            </widget>
           </item>
           <item>
            <widget class="QCheckBox" name="checkBoxYellowArea">
             <property name="text">
              <string>Yellow Area</string>
             </property>
            </widget>
           </item>
           <item>
            <widget class="QCheckBox" name="checkBoxGreenArea">
             <property name="text">
              <string>Green Area</string>
             </property>
            </widget>
           </item>
          </layout>
         </item>
         <item row="1" column="0">
          <layout class="QHBoxLayout" name="horizontalLayout_3">
           <item>
            <widget class="QPushButton" name="pushButton">
             <property name="text">
              <string>Add Message</string>
             </property>
            </widget>
           </item>
           <item>
            <widget class="QLineEdit" name="lineEdit"/>
           </item>
           <item>
            <widget class="QComboBox" name="comboBox">
             <item>
              <property name="text">
               <string>Select Option Distance</string>
              </property>
             </item>
             <item>
              <property name="text">
               <string>[ INFO] Minimum Distance: 5</string>
              </property>
             </item>
             <item>
              <property name="text">
               <string>[ INFO] Minimum Distance: 10</string>
              </property>
             </item>
             <item>
              <property name="text">
               <string>[ INFO] Minimum Distance: 15</string>
              </property>
             </item>
             <item>
              <property name="text">
               <string>[ INFO] Minimum Distance: 20</string>
              </property>
             </item>
            </widget>
           </item>
          </layout>
         </item>
        </layout>
       </widget>
      </item>
      <item>
       <layout class="QHBoxLayout" name="horizontalLayout_2">
        <item>
         <widget class="QListView" name="listView"/>
        </item>
        <item>
         <widget class="QGraphicsView" name="graphicsView">
          <property name="styleSheet">
           <string notr="true">background-color: rgb(211, 215, 207);</string>
          </property>
         </widget>
        </item>
       </layout>
      </item>
     </layout>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>555</width>
     <height>22</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

What I have done so far:

I have been doinf a lot of research about this problem and came across this source which was useful but could not solve the problem, but in addition it seems to use a QModelIndex and I am not sure this is exactly what I need for this small project.

Also I read this source which was useful to establish and capture the specific and unique string but in terms of changing colors I could not solve that.

I also came across this which led me to give a try to the following:

void MainWindow::changeColorDetection()
{
    // if [ INFO] Minimum Distance: 5 inside QListView
    // Than change color of the QGraphicsView background
    QModelIndex index = ui->listView->currentIndex();
    QString itemText = index.data(Qt::DisplayRole).toString();
    if(itemText.startsWith("[ INFO] Minimum Distance: 10"))
    {
        QColor bg = ui->graphicsView->palette().background().color();
        ui->graphicsView->setStyleSheet(QString("background-color:") + bg.name(QColor::HexArgb));
    }
}

But also this last one did not result in any change in the background.

What am I missing? Thank you very much for pointing to the right direction for solving this issue.