Why doesn't ComboBox show the Selected Item? - qt

Question

Here's what I've in my QML:
import QtQuick 2.12
import QtQuick.Window 2.12
import QtQuick.Controls 2.5
import QtQuick.Layouts 1.3
Window {
visible: true
width: 640
height: 480
title: "Test Window"
ComboBox{
width: 300
model: testContext.List
delegate: ItemDelegate{
width: parent.width
contentItem: RowLayout{
Text{ text: modelData.name }
Text{
text: " | " + modelData.age
Layout.alignment: Text.AlignRight
}
}
background: Rectangle{ color: hovered? "green" : "white" }
}
}
}
When I click on the ComboBox I see items in the popup list BUT the selected item doesn't appear in the box!
If I set textRole: "name", it shows only the name property in the box but I want the whole formatted text, defined in ItemDelegate, in the box.
Here in the illustration they've one more contentItem beside the one in delegate:
contentItem: Text {
...
text: control.displayText
...
}
It still doesn't show the formatted text in the box even if I add the additional contentItem in my QML.
EDIT
Here's the ViewModel .h:
#ifndef TEST_H
#define TEST_H
#include <QObject>
#include <QQmlApplicationEngine>
#include <QQmlContext>
#include <QVector>
#include "aclass.h"
#include "Property.h"
class Test : public QObject
{
Q_OBJECT
PROPERTY(QVector<AClass*>, List)
public:
explicit Test(QObject *parent = nullptr);
private:
QQmlApplicationEngine engine;
};
#endif // TEST_H
the .cpp:
#include "test.h"
Test::Test(QObject *parent) : QObject(parent)
{
engine.rootContext()->setContextProperty("testContext", this);
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
for(int i = 0; i < 10; i++){
auto a = new AClass();
a->setname("Item " + QString::number(i));
a->setage(i + 10);
m_List.push_back(a);
}
emit ListChanged();
}
and the main.cpp:
#include <QGuiApplication>
#include "test.h"
int main(int argc, char *argv[])
{
QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
QGuiApplication app(argc, argv);
Test test;
return app.exec();
}
for the Q_PROPERTY I've a macro PROPERTY with the following content:
#ifndef PROPERTY_H
#define PROPERTY_H
#define PROPERTY(QType, name) \
Q_PROPERTY(QType name READ name WRITE set##name NOTIFY name##Changed) \
public: \
QType name(){return m_##name;} \
void set##name(QType value){m_##name = value; emit name##Changed();} \
Q_SIGNAL void name##Changed(); \
private: \
QType m_##name;
#endif // PROPERTY_H
Here's AClass:
#ifndef ACLASS_H
#define ACLASS_H
#include <QObject>
#include "Property.h"
class AClass : public QObject
{
Q_OBJECT
PROPERTY(QString, name)
PROPERTY(int, age)
};
#endif // ACLASS_H

Answer 1

For that I've to use the additional contentItem outside the ItemDelegate like this:
contentItem: RowLayout{
Text{ text: model[control.currentIndex].name }
Text{
text: " | " + model[control.currentIndex].age
horizontalAlignment: Text.AlignRight
Layout.fillWidth: true
}
}
and I've to give the ComboBox an id, here in the example control is the id