Very simple Rectangle example exiting immediately after app runs

enjoysmath

This screenshot has the full description of what I'm doing:

I ran qmake after "adding existing file > S3.png" to the resources.

The app runs then shows that output below in the screenshot. Not sure what to do, but the example is taken from:

https://qmlbook.github.io/ch04-qmlstart/qmlstart.html

"RectangleExample.qml"

enjoysmath

Stick the whole thing in a Window and it should work:

import QtQuick 2.12
import QtQuick.Window 2.12

Window {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")

    Rectangle {
        id: root
        width: 120; height: 240
        color: "#4A4A4A"
        Image {
            id: triangle
            x: (parent.width - width)/2; y: 40
            source: "S_3.png"
        }
        Text {
            y: triangle.y + triangle.height + 20
            width: root.width
            color: 'white'
            horizontalAlignment: Text.AlignHCenter
            text: 'Triangle'
        }
    }

}