<div>Dear All,</div><div> </div><div>I&#39;m a beginner for javascript, OpenLayers, ExtJS and GeoExt. </div><div>I&#39;m developing a web map with multi-based layers from google.</div><div>However, when I used the following code, there is the white layer over the google based layer after the map is rendered.</div>
<div>How could I solve this problem? I also attached the full code.</div><div> </div><div>Thank in advanced.</div><div> </div><div>Wangsom</div><div> </div><div><br>    var mapOptions = {<br>        controls: [<br>        new OpenLayers.Control.Navigation(),<br>
        new OpenLayers.Control.PanZoomBar(),<br>        new OpenLayers.Control.ScaleLine(),<br>        new OpenLayers.Control.KeyboardDefaults()<br>        ],<br>        allOverlays: false,<br>        projection: &quot;EPSG:900913&quot;,<br>
        units: &#39;m&#39;<br>    };</div><div> </div><div>    var map = new OpenLayers.Map(&#39;map&#39;, mapOptions);</div><div> </div><div>    var gmap = new OpenLayers.Layer.Google(<br>        &quot;Google Map&quot;, // the default<br>
        {<br>            type: google.maps.MapTypeId.ROADMAP,<br>            numZoomLevels: 20<br>        }, {<br>            isBaseLayer: true,<br>            buffer: 0,<br>            visibility: false<br>        }<br>        );</div>
<div> </div><div>    var gsat = new OpenLayers.Layer.Google(<br>        &quot;Google Satellite&quot;,<br>        {<br>            type: google.maps.MapTypeId.SATELLITE,<br>            numZoomLevels: 22<br>        }, {<br>
            isBaseLayer: true,<br>            buffer: 0,<br>            visibility: false<br>        }<br>        );</div><div> </div><div>    var gphy = new OpenLayers.Layer.Google(<br>        &quot;Google Terrain&quot;,<br>
        {<br>            type: google.maps.MapTypeId.TERRAIN,<br>            numZoomLevels: 22<br>        }, {<br>            isBaseLayer: true,<br>            buffer: 0,<br>            visibility: false<br>        }<br>        );</div>
<div> </div><div>    var ghyb = new OpenLayers.Layer.Google(<br>        &quot;Google Hybrid&quot;,<br>        {<br>            type: google.maps.MapTypeId.HYBRID,<br>            numZoomLevels: 22<br>        }, {<br>            isBaseLayer: true,<br>
            buffer: 0,<br>            visibility: false<br>        }<br>        );</div><div> </div><div>    var boundary = new OpenLayers.Layer.WMS(&quot;Tasmania State Boundaries&quot;,<br>        localUrl, {<br>            layers: &quot;topp:tasmania_state_boundaries&quot;,<br>
            transparent: true,<br>            format: &quot;image/png&quot;<br>        }, {<br>            isBaseLayer: false,<br>            opacity: 0.2,<br>            visibility: true,<br>            buffer: 0,<br>            displayOutsideMaxExtent: true<br>
        });</div><div> </div><div>    var water =  new OpenLayers.Layer.WMS(&quot;Water&quot;,<br>        localUrl, {<br>            layers: &quot;topp:tasmania_water_bodies&quot;,<br>            transparent: true,<br>            format: &quot;image/png&quot;<br>
        }, {<br>            isBaseLayer: false,<br>            visibility: true,<br>            buffer: 0,<br>            displayOutsideMaxExtent: true<br>        });</div><div> </div><div>    var city = new OpenLayers.Layer.WMS(&quot;Cities&quot;,<br>
        localUrl, {<br>            layers: &quot;topp:tasmania_cities&quot;,<br>            transparent: true,<br>            format: &quot;image/png&quot;<br>        }, {<br>            isBaseLayer: false,<br>            visibility: true,<br>
            buffer: 0,<br>            displayOutsideMaxExtent: true<br>        });</div><div> </div><div>    var road = new OpenLayers.Layer.WMS(&quot;Tasmania Roads&quot;,<br>        localUrl, {<br>            layers: &quot;topp:tasmania_roads&quot;,<br>
            transparent: true,<br>            format: &quot;image/png&quot;<br>        }, {<br>            isBaseLayer: false,<br>            visibility: true,<br>            buffer: 0,<br>            displayOutsideMaxExtent: true<br>
        });</div><div> </div><div>    map.addLayers([ghyb, gsat, gphy, gmap, boundary, water, city, road]);</div><div> </div><div>    var mapPanel = new GeoExt.MapPanel({<br>        map: map,<br>        center: new OpenLayers.LonLat(146.64681, -42.16430).transform(<br>
            new OpenLayers.Projection(&quot;EPSG:4326&quot;),<br>            map.getProjectionObject()),<br>        zoom: 7,<br>        region: &quot;center&quot;,<br>        layout: &quot;fit&quot;<br>    });</div><div> </div>
<div> </div><div> </div>