Using a fixed map in the OpenLayers 3 Overview Map

Question

Is there a way to 'lock' the overview map in OpenLayers 3 using a fixed extent?

The current implementation resizes the little rectangle and the map. So when I zoom in or out in my map, the map in the overview map might change as well.

However, I would like the map in the overview map to use a fixed extent, so that it never moves. So when I zoom or pan the map always stays the same and only the rectangle is adjusted.

The Overview Panel in QGIS provides a good example of what I mean.

In the following screenshots I am moving and zooming in QGIS, but my overview map always stays the same and solely the rectangle is adjusted.

I would like to implement that behavior in OpenLayers 3 or 4.

Answer 1

Just define a view for your overview map:

var overviewMapControl = new ol.control.OverviewMap({
  view: new ol.View({
    maxZoom: 14,
    minZoom: 14,
    zoom: 14
  })
});

map = new ol.Map({
  controls: ol.control.defaults().extend([
    overviewMapControl
  ]),
  other map options
});