Dynamic Polyline in Qt Location/Map

[mkhtrmn]

Hello,

I want to create an application which allow me to draw polyline when I click two points somewhere on the map. Something like googlemap.

I managed to draw one polyline, but how to create more than one polyline?
main.qml

import QtQuick 2.6
import QtQuick.Window 2.2
import "componentCreation.js" as MyScript
import QtQuick.Controls 2.1
import QtLocation 5.3
import QtPositioning 5.2

Window {
    id: appWindow
    width: 512
    height: 512
    visible: true
    Map {
        id: map
        //width: win.width - kolom.width - row1.spacing
        anchors.fill: parent
        activeMapType: map.supportedMapTypes[2]
        zoomLevel: 1
        //z:1


        center {
            latitude: 5
            longitude: 100
        }
        plugin: Plugin {
            name: 'osm';
            PluginParameter {
                name: 'osm.mapping.offline.directory';
                value: ':/offline_tiles/'
            }
        }
        MapCircle {
            radius: 800000
            color: 'blue'
            center {
                latitude: 5
                longitude: 100
            }
        }

        MouseArea {
            anchors.fill: parent
            onPressed: {
                var coord = map.toCoordinate(Qt.point(mouse.x,mouse.y))
                console.log("coordinate: " + coord)

                //MyScript.createSpriteObjects(map.toCoordinate(Qt.point(mouse.x,mouse.y)).latitude,map.toCoordinate(Qt.point(mouse.x,mouse.y)).longitude)
                MyScript.createSpriteObjects(mouse.x,mouse.y)

            }
        }
    }


}

componentCreation.js

var component
var sprite

function createSpriteObjects(posX,posY) {
    component = Qt.createComponent("Sprite.qml");
    if (component.status == Component.Ready)
        finishCreation(posX,posY);
    else
        component.statusChanged.connect(finishCreation);

}

function finishCreation(posX,posY) {
    if (component.status == Component.Ready) {
        //sprite = component.createObject(map, {"marker.coordinate": map.toCoordinate(Qt.point(posX,posY))});
        sprite = component.createObject(map);
        console.log("Object Created " + map.toCoordinate(Qt.point(posX,posY)));
        //sprite = component.createObject(appWindow);
        if (sprite == null) {
            console.log("Error creating Object");
        }
    }
    else if (component.status == Component.Error) {
        console.log("Error loading component:", component.errorString());
    }
}

Sprite.qml

import QtQuick 2.0
import QtLocation 5.3


MapQuickItem {
    id: marker
    sourceItem: Image {
        id: image
        source: "marker.png"
    }
    coordinate {
        latitude: 5
        longitude: 100
    }
    anchorPoint.x: image.width / 2
    anchorPoint.y: image.height / 2
    visible: true
}

/*Rectangle {
    width: 100
    height: 20
    x: 10
    y:10
}*/

[koahnig]

@mkhtrmn

Probably you need to show the source code.

Crystall ball reading tells me that you are deleting or refreshing some view while preparing for the next polyline.

[ofmrew]

@mkhtrmn

Try the following:
QVector<QLineF> polyPath;
polyPath.append(QLineF(p1p, p1));
p.drawLines(polyPath);

The first line creates a container for the line segments; the second add the line segments to the container; and the third draws the segments. You can add as many polylines as required, since they are treated as individual line segments.

[mkhtrmn]

@ofmrew said in Dynamic Polyline in Qt Location/Map:

@mkhtrmn

Try the following:
QVector<QLineF> polyPath;
polyPath.append(QLineF(p1p, p1));
p.drawLines(polyPath);

The first line creates a container for the line segments; the second add the line segments to the container; and the third draws the segments. You can add as many polylines as required, since they are treated as individual line segments.

Thanks for the recommendation. Actually, I am working on QML and I use MapPolyline to draw on the map.

I have made a progress, I can create a rectangle dynamicaly using QML dynamic object creation. But, when I tried to draw a MapQuickItem or MapCircle it shows nothing.

*I have updated my post with my code

[mkhtrmn]

@koahnig I have updated my post by adding the source code

[koahnig]

@mkhtrmn

Sorry, QML is not my field of expertize at all.

My guess is that you are displaying something with a local instance and therefore, it is vanishing for the next trial. However, with QML there is no chance that I can help.

I will move your post to QML forum.

[oria66]

So, this post is old relatively. However, it is marked as UNSOLVED. Anyway, there is someone that can be helpful.

This is the funcionality asked: dynamic polyline with two modes. One mode is continous polilyne, the other is an array of single lines. The code speak by itself.

main.qml

ApplicationWindow {
    id: applicationWindow
    visible: true
    width: 640
    height: 480

    // This property indicates the mode, if changeMode=0 is a polyline,
    // if changeMode=OtherNumber is an array or single lines
    property int changeMode: 1

    Plugin {
        id: osmMapPlugin
        name: "osm"
    }

    Map {
        id: themap
        anchors.fill: parent
        zoomLevel: 12
        plugin: osmMapPlugin
        center: QtPositioning.coordinate(-34.171634, -70.734406)
    }

    MouseArea{
        anchors.fill: parent
        z:1
        onClicked: {
            MyScript.createElements(Qt.point(mouse.x,mouse.y))
        }
    }
}

Line.qml

MapPolyline {

    property alias mainPolyline: mainPolyline

    id: mainPolyline
    line.width: 3
    line.color: 'blue'
}

Marker.qml

MapQuickItem {

    property alias marker: marker

    id: marker
    sourceItem: Rectangle {
        width: 10
        height: 10
        color: "red"
        smooth: true
        radius: 15
    }
    opacity: 1.0
    anchorPoint: Qt.point(sourceItem.width/2, sourceItem.height/2)
}

componentCreation.js (import as MyScript)

var arrayLines=[]
var lineComplete=false

function createElements(point) {

    var componentMarker = Qt.createComponent("Marker.qml");

    if (componentMarker.status === Component.Ready) {
        var markerFirstCorner = componentMarker.createObject(themap);
        markerFirstCorner.coordinate = themap.toCoordinate(point)

        themap.addMapItem(markerFirstCorner)
    }else{
        console.log("Marker not created")
    }

    var theLine

    if(changeMode===0){

        //Polyline mode
        if(arrayLines.length===0){
            createLine(point)
        }else{
            theLine = arrayLines[arrayLines.length-1]

            theLine.mainPolyline.addCoordinate(themap.toCoordinate(point))
        }

    }else{
        //Array of lines

        if(arrayLines.length===0 || !lineComplete){
            createLine(point)
            lineComplete=true
        }else{
            theLine = arrayLines[arrayLines.length-1]

            theLine.mainPolyline.addCoordinate(themap.toCoordinate(point))

            lineComplete=false
        }
    }
}

function createLine(point){

    var componentLine = Qt.createComponent("Line.qml")

    if (componentLine.status === Component.Ready) {
        var lineFirstCorner = componentLine.createObject(themap);
        lineFirstCorner.mainPolyline.addCoordinate(themap.toCoordinate(point))

        themap.addMapItem(lineFirstCorner)
        arrayLines.push(lineFirstCorner)
    }else{
        console.log("Line not created")
    }
}