I have a featurelayer that consists of points. by clicking some row on the table grid, the map view is switched and only one selected point is displayed
by the JavaScript command:
featureLayer.setDefinitionExpression("ID="+num);
Now my goal is to center the map to this point
First you must get the graphic from featureLayer by featureLayer.graphics. Then use map.centerAndZoom(mapPoint, levelOrFactor) or map.centerAt(mapPoint) to zoom to your graphic.
var graphic = featureLayer.graphics[0];
if (graphic && graphic.geometry.type === "point") {
map.centerAndZoom(graphic.geometry, 17); // or map.centerAt(graphic.geometry);
}
Related
I am using ArcGIS API v4.8 and the drawing tools to draw circle on my map.
1 issue I notice is when I draw a circle, the center of the circle moves when I move my mouse resizing the circle rather than fixed at the point of the 1st mouse click starts:
How do I fix the center regardless of how I move the radius of the circle? What is missing in my code?
const options = {view, layer: tempGraphicsLayer, pointSymbol, polylineSymbol, polygonSymbol}
let sketchViewModel = new SketchViewModel(options)
let drawCircleButton = document.getElementById('circleButton')
drawCircleButton.onclick = function () {
clear()
isDrawLine = false
sketchViewModel.create('polygon', {mode: 'click'})
sketchViewModel.create('circle')
}
EDIT:
I have found a similar sample, choose the Draw Circle tool, start drawing a circle on the map, you will notice that the center of the circle moves when you move your mouse, I want it to fix the center instead.
The problem when the center moves along with your mouse move is that the circle drawn is not accurate, as I want to start with the center of the circle I want, the circle can expand outward but the center should not move.
That is because the circle, in the given example, is being draw inside the square object. Basically your start and end point are representing corners, not the center point and outer layer of the circle. So every time you expand circle object, it expands from one corner, while the rest is dragging along your mouse.
Visual example:
There are workarounds for this of course. I've made a small sample code of one of the possible ways to draw a circle from a fixed center point.
https://jsfiddle.net/wLd46g8k/9/
Basically I used an ArcGis JS API 4.x constructor called Circle, where you pass a starting point and radius. In my example I've calculated the radius from these two points.
function drawCircle(){//draws the circle
graphicsLayer.graphics.removeAll();
var graphic = new Graphic({
geometry: new Circle({//circle constructor
center: startPoint,//pass the pointer-down event X Y as a starting point
radius: Math.floor(Math.sqrt(Math.pow(startPoint.x - endPoint.x, 2) + Math.pow(startPoint.y - endPoint.y, 2)))
}), //calculates endpoint distance from the startpoint and pass it as a radius
symbol: {//circle design
type: "simple-fill",
color: "orange",
style: "solid",
outline:{
color:"darkorange",
width:4
}
}
});
graphicsLayer.graphics.add(graphic);//adds the circle
};
I'm building a dynamic graph with cytoscape.js over a world map generated with jVectorMap.
Starting with coordinates in LAT / LON format from json data, I can convert them in point.x / point.y over the generated map with:
var nodePoint = theMap.latLngToPoint(node.data.lat, node.data.lon)
and then I can add the new node in the graph with:
cy.add({
group: "nodes",
position: { x: nodePoint.x, y: nodePoint.y },
style: {
'background-color': node.color
},
data: {
id: node.id,
name: node.label,
customData: node.data,
}
})
This part works, but when json returns multiple nodes with the same coordinates, I would like to spread these nodes around the point with the common LAT / LON information.
I'm able to identify these nodes and apply a dedicated layout to them, but the resulting layount is located in the center of the screen / div of graph.
What I want to know is if there is a simple way to apply a Circle Layout with specific center point.
(I would like to avoid implementing the solution that I'm evaluating... i.e to build a bounding box around the center point and see what happens, (with the bounding box size that grows along with node number in the same point))
In the Wine and cheese example included in the documentation they use the bounding box to force a concentric layout around a selected node ( http://js.cytoscape.org/demos/cde4db55e581d10405f5/ ).
While you indicate you would like to avoid this solution it seems a straightforward solution. The implementation in the example is rather elegant.
I just started using Leaflet and Marker Clusterer to organize the markers.
Problem #1: When an unclustered marker is clicked, no popup appears.
Problem #2: When a cluster is clicked several times, all the markers within that cluster appears, and when one of this marker is clicked, its popup appears! However, after closing the popup by clicking on the map, clicking on any of these clustered markers do not open any popups!
If I only have 3 unclustered markers, the popup works fine. However, as more markers are added, once a cluster forms, clicking on the marker within any cluster will not cause the popup to open!
Initializing markerclusterer
markers = new L.MarkerClusterGroup();
map.addLayer(markers);
All markers added to markercluster markers
A loop calls on the render function to create the marker and add it to the markerclusterer's array markers. (ignore the backbone.js code)
ListingMarkerView = Backbone.View.extend({
template: _.template( $('#tpl_ListingMarkerView').html() ),
render: function() {
// Create marker
var content = this.template( this.model.toJSON() );
var marker = new L.marker(
[this.model.get('lat'), this.model.get('lng')],
{content: content});
marker.bindPopup(content);
// Add to markerclusterer
markers.addLayer(marker);
}
});
Without markerclusterer
If I add the marker directly to map instead of the markerclusterer array markers, the popups work fine, so I guess the problem has something to do with markerclusterer.
Did I do something wrong that resulted in such behavior of the popups? All help appreciated, thanks!
From what little I know of the cluster marker group, you should do this:
var markerGroup = new L.MarkerClusterGroup();
markerGroup.on('click', function(ev) {
// Current marker is ev.layer
// Do stuff
});
To add an event handler to the cluster layer instead, do this:
markerGroup.on('clusterclick', function(ev) {
// Current cluster is ev.layer
// Child markers for this cluster are a.layer.getAllChildMarkers()
// Do stuff
});
Oh, and read the github README carefully, it's all in there...
Make sure you have the right versions of everything in your Leaflet + Clusterer stack (Js and Css). Compare against the examples in the Clusterer Github repo.
How do I specify zoom level for google maps in a kml file or why is it that my zoom level gets over ridden when I load this file. My question is actually how do I control zoom of a map for the following link:
http://code.google.com/apis/maps/documentation/javascript/examples/layer-kml-features.html
By default, the map is centered and zoomed to the bounding box of the contents of the kml layer.
You can change the default behaviour with preserveViewport property of google.maps.KmlLayerOptions object. If you set it to true the map isn't centered and zoomed.
In the example, use:
var nyLayer = new google.maps.KmlLayer(
'http://www.searcharoo.net/SearchKml/newyork.kml',
{
suppressInfoWindows: true,
map: map,
preserveViewport: true
});
If you want to center and zoom to the contents of the kml layer later, use:
var bounds = nyLayer.getDefaultViewport();
map.fitBounds(bounds);
EDIT:
If you want the map to be always centered (but not zoomed) when the kml layer is loaded, utilize defaultviewport_changed event of the google.maps.KmlLayer object. You have to set the map center to the center of the kml layer default viewport. The event is triggered when the contents of the kml layer are loaded and its default viewport is computed.
google.maps.event.addListener(nyLayer, 'defaultviewport_changed', function() {
var bounds = nyLayer.getDefaultViewport();
map.setCenter(bounds.getCenter());
});
I've got a problem to render an esri Map with sencha touch. I display a tabPanel with a tab containing the map, and 3 other tabs.
My problem is that when I'm on another tab than the map-tab, when I resize the window (or change orientation of phone), the map diseapears.
I identified the source of the problem. when I resize the window being on another tab, the map tab goes from current size to 0x0 to the new size. Problem is that when the width and height are set to 0x0, the Esri Map require tiles of dimension 0x0, and then the error appears.
I tried to set minWidth and minHeight to my tab but without success.
do you have any clue how i could fix that ??
thank you in advance !
I believe I had the same problem (I didn't really know the exact cause at the time). Whenever the orientation of the screen changed I was manually changing the dimensions of the esri map to match the panel and then firing the map's reposition and resize methods. However, if this was fired from a different panel, the basemaps would drop out of the map.
I was able to fix this by calling the following function every time orientation changed, or the map panel was set as active:
function resizeMapDiv(){
if (appPanel.getActiveItem() === mapPanel){
var mapdiv = document.getElementById('mapDiv');
var mappanel = document.getElementById('mapPanel');
if ((mapdiv != null) && (mappanel != null) && (mapdiv.style.width != mappanel.style.width)){
mapdiv.style.width = mappanel.style.width;
mapdiv.style.height = mappanel.style.height;
map.reposition();
map.resize();
}
}
}