Hide the highlight of a ListView while scrolling - qml

Question

I am building a Qt5 application based on Qt-Quick 2 for the UI. I have an issue while displaying a ListView with an highlight component. When I scroll the ListView the highlight rectangle is visible outside of the ListView and I can't find a way to avoid it.
Here is an example of the issue with a minimal QML file:
import QtQuick 2.0
Rectangle {
width: 360; height: 600
ListView {
width: 350; height: 200
anchors.centerIn: parent
id: myList
model: myModel
highlight: highlightBar
delegate: Item {
width: 400; height: 20
Text { text: name }
MouseArea {
id: mArea
anchors.fill: parent
onClicked: { myList.currentIndex = index; }
}
}
}
Component {
id: highlightBar
Rectangle {
width: parent.width; height: 20
color: "#FFFF88"
}
}
ListModel {
id: myModel
}
/* Fill the model with default values on startup */
Component.onCompleted: {
for(var i = 0; i < 100; i++) {
myModel.append({ name: "Big Animal : " + i});
}
}
}
Is there a way to "limit" a component to its parent borders or to hide the highlight component while scrolling?

Answer 1

As reported by the documentation:
Note: Views do not enable clip automatically. If the view is not clipped by another item or the screen, it will be necessary to set clip: true in order to have the out of view items clipped nicely.
Hence, what you are experiencing is a common behaviour and you should either 1) clip the view via other Items (e.g. a header Rectangle and a footer Rectangle with z:infinite or simply set the clip property to true, i.e.
ListView{
//...
clip:true
//...
}
Clipping has some perfomance disavantages which can greatly affect the application as it grows. Hence, its usage, especially outside the views scenario, should be evaluated carefully.