Map object

Basic class of OpenLayers is the OpenLayers.Map. It is the main view at your map application.

It has one mandatory parameter - div id, where the map is to be rendered.

Have a look in the documentation, how to initialize the map.

Several methods are available, among others:

addLayer (OpenLayers.Layer) – add layer to the map

setLayerIndex (OpenLayers.Layer, Integer) – set index of the layer in

layer stack

addControl (OpenLayers.Control) && addControls([OpenLayers.Control]) –

add control feature to the map (layerswitcher, scalebar, overview map, ...)

addPopup (OpenLayers.Popup) – add popup to the map

setCenter (OpenLayers.LonLat, Integer, ...) – set new center of the

map

getExtent () – returns OpenLayers.Bounds – current map extent

getResolution, getUnits, getScale,... – self explaining

getZoomForExtent (OpenLayers.Bounds) – get zoom level for given

extent

getResolutionForZoom (Integer) – get resolution for given zoom level

getZoomForResolution (Float) – get zoom for given resolution

zoomTo, zoomIn, zoomOut, zoomToExtent, zoomToMaxExtent, zoomToScale, ...

getLonLatFromPixel, getPixelFromLonLat, ...

And several attributes:

layers – list of layers

scales, resolutions,...

projection, units, ...

You will probably need most of selected attributes and methods, and possibly several others.

Example of creating map object the easiest way:

var map = new OpenLayers.Map("map1");

Example of creating map object in more complicated way:

var map = new OpenLayers.Map("map", {
        scales: [2000000,1000000,500000,200000,100000,50000,20000,10000,5000],
        units: "m",
        projection: "epsg:102067",
        maxExtent: new OpenLayers.Bounds(-905000,-1230000,-400000,-900000)
    });