JavaScript/jQuery VectorMap Methods
This section describes the methods that can be used in code to manipulate objects related to the UI component.
beginUpdate()
Postpones rendering that can negatively affect performance until the endUpdate() method is called.
The beginUpdate() and endUpdate() methods reduce the number of renders in cases where extra rendering can negatively affect performance.
See Also
center()
This method returns the center coordinates as an array of two values in the [longitude, latitude] format.
See Also
center(centerCoordinates)
To change the coordinates of the map center, pass an array of two values in the [longitude, latitude] form as the argument to the center(centerCoordinates) method.
In addition, you can get the current coordinates of the map center by calling the same method without arguments. Moreover, you can perform specific actions when the center coordinates are changed. For this purpose, implement a callback function and assign it to the onCenterChanged property.
See Also
clearSelection()
Deselects all the selected area and markers on a map at once. The areas and markers are displayed in their initial style after.
convertToGeo(x, y)
Converts coordinates from pixels to the dataSource coordinate system.
convertToXY(longitude, latitude)
Converts coordinates from the dataSource coordinate system to pixels.
dispose()
jQuery
After calling this method, remove the DOM element associated with the UI component:
$("#myVectorMap").dxVectorMap("dispose");
$("#myVectorMap").remove();Angular
Use conditional rendering instead of this method:
<dx-vector-map ...
*ngIf="condition">
</dx-vector-map>Vue
Use conditional rendering instead of this method:
<template>
<DxVectorMap ...
v-if="condition">
</DxVectorMap>
</template>
<script>
import DxVectorMap from 'devextreme-vue/vector-map';
export default {
components: {
DxVectorMap
}
}
</script>React
Use conditional rendering instead of this method:
import React from 'react';
import VectorMap from 'devextreme-react/vector-map';
function DxVectorMap(props) {
if (!props.shouldRender) {
return null;
}
return (
<VectorMap ... >
</VectorMap>
);
}
class App extends React.Component {
render() {
return (
<DxVectorMap shouldRender="condition" />
);
}
}
export default App;endUpdate()
Refreshes the UI component after a call of the beginUpdate() method.
The beginUpdate() and endUpdate() methods reduce the number of renders in cases where extra rendering can negatively affect performance.
See Also
getInstance(element)
getInstance is a static method that the UI component class supports. The following code demonstrates how to get the VectorMap instance found in an element with the myVectorMap ID:
// Modular approach
import VectorMap from "devextreme/viz/vector_map";
...
let element = document.getElementById("myVectorMap");
let instance = VectorMap.getInstance(element) as VectorMap;
// Non-modular approach
let element = document.getElementById("myVectorMap");
let instance = DevExpress.viz.dxVectorMap.getInstance(element);See Also
getSize()
Returns an object with the following fields.
- width
The width of the UI component in pixels. - height
The height of the UI component in pixels.
See Also
hideLoadingIndicator()
Although the loading indicator hides automatically once the UI component is ready, you can hide it from code at the required moment using this method.
See Also
on(eventName, eventHandler)
Use this method to subscribe to one of the events listed in the Events section.
See Also
on(events)
Use this method to subscribe to several events with one method call. Available events are listed in the Events section.
See Also
render()
Normally, the UI component redraws itself automatically after the browser window is resized. But on rare occasions, you may need to request the redrawing, for example, after the UI component's container is resized. For this purpose, call the render() method.
See Also
viewport()
This method returns the viewport coordinates as an array of four values in the [minLongitude, maxLatitude, maxLongitude, minLatitude] form.
See Also
viewport(viewportCoordinates)
To change the coordinates of the map viewport, pass an array of four values in the [minLongitude, maxLatitude, maxLongitude, minLatitude] form as the argument to the viewport(viewportCoordinates) method. If the passed coordinates do not fit the aspect ratio of the UI component container precisely, either the latitude or longitude will be applied depending on the largest range.
In addition, you can get the current coordinates of the map viewport by calling the same method without arguments.
If you have implemented the onCenterChanged or onZoomFactorChanged callback functions, they will be triggered when the viewport coordinates are changed using the viewport(viewportCoordinates) method.
See Also
zoomFactor(zoomFactor)
To change the zoom factor, pass an numeric value as the argument to the zoomFactor(zoomFactor) method.
In addition, you can get the current value of the map zoom factor by calling the same method without arguments. Moreover, you can perform specific actions when the zoom factor is changed. For this purpose, implement a callback function and assign it to the onZoomFactorChanged property.