Dynamically change custom host URL of osm Plugin in a QML Map - qt

Question

I have a custom chart host with several tiled maps in a directory structure:
http://host/New_York/
http://host/Washington/
http://host/Montreal/
The QML application has a ComboBox component that allows the user to select which chart he wants to display.
The Map component uses the osm Plugin with a PluginParameter pointing to the URL to use for the chart. I thought I could simply dynamically assign a value to this PluginParameter, but it does not work, the value remains unchanged even after assigning it. I also tried destroying the Plugin object, recreating it and assigning it to the Map object, but I get an error saying that the plugin property is ReadOnly.
What is the proper way to dynamically change the custom host URL of a Plugin object used by a Map component?
Plugin {
id: mapPlugin
name: "osm"
PluginParameter { id: charturl; name: "osm.mapping.custom.host"; }
}
Map {
id: mapview
plugin: mapPlugin
activeMapType: supportedMapTypes[supportedMapTypes.length - 1]
...
ComboBox {
...
onCurrentIndexChanged: {
charturl.value = cbItems.get(currentIndex).url
...

Answer 1

The Plugin can only be written once, so you cannot change it later, so in this you will have to create a new map using Loader:
main.qml
import QtQuick 2.14
import QtQuick.Window 2.14
import QtQuick.Layouts 1.14
import QtQuick.Controls 2.14
import QtLocation 5.14
import QtPositioning 5.14
Window {
visible: true
width: 640
height: 480
ColumnLayout {
anchors.fill: parent
ComboBox {
id: combobox
model: [
"http://host/New_York/",
"http://host/Washington/",
"http://host/Montreal/"
]
Layout.fillWidth: true
onActivated: changeHost()
}
Loader{
id: loader
Layout.fillWidth: true
Layout.fillHeight: true
onStatusChanged: if (loader.status === Loader.Ready) console.log('Loaded')
}
Component.onCompleted: changeHost()
}
function changeHost(){
var item = loader.item
var zoomLevel = item ? item.zoomLevel: 14
var center = item ? item.center: QtPositioning.coordinate(59.91, 10.75)
loader.setSource("MapComponent.qml", {
"host": combobox.currentValue,
"center": center,
"zoomLevel": zoomLevel}
)
}
}
MapComponent.qml
import QtLocation 5.14
Map {
id: map
property string host: ""
plugin: Plugin {
name: "osm"
PluginParameter {
name: "osm.mapping.custom.host"
value: map.host
}
}
activeMapType: supportedMapTypes[supportedMapTypes.length - 1]
}