bd262fce41
Now the application no longer needs to care about the tile origin, because the CacheWrite control modifies the url if the CORS image loading is disabled and it is from a different origin. This only requires OpenLayers.ProxyHost to be properly configured. Also local storage keys use the original url instead of the proxied url, to make the CacheRead control work without proxy settings. No deferred exceptions are thrown any more. Instead, OpenLayers.Console is used to show an error message for security exceptions. We now check for OpenLayers.Tile.Image, because other tile types (e.g. UTFGrid) are not supported (yet). To make the same origin handling in the CacheWrite control easier, OpenLayers.Request now exposes the same origin logic from request.issue as a separate function, so it can also be used by other components.
48 lines
1.4 KiB
JavaScript
48 lines
1.4 KiB
JavaScript
// Use proxy to get same origin URLs for tiles that don't support CORS.
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OpenLayers.ProxyHost = "proxy.cgi?url=";
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var map, cacheWrite;
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function init() {
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map = new OpenLayers.Map({
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div: "map",
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projection: "EPSG:900913",
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layers: [
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new OpenLayers.Layer.WMS("OSGeo", "http://vmap0.tiles.osgeo.org/wms/vmap0", {
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layers: "basic"
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}, {
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eventListeners: {
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tileloaded: updateStatus
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}
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})
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],
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center: [0, 0],
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zoom: 1
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});
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cacheWrite = new OpenLayers.Control.CacheWrite({
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autoActivate: true,
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imageFormat: "image/jpeg",
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eventListeners: {
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cachefull: function() { status.innerHTML = "Cache full."; }
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}
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});
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map.addControl(cacheWrite);
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// User interface
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var status = document.getElementById("status");
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document.getElementById("clear").onclick = function() {
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OpenLayers.Control.CacheWrite.clearCache();
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updateStatus();
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};
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// update the number of cached tiles and detect local storage support
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function updateStatus() {
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if (window.localStorage) {
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status.innerHTML = localStorage.length + " entries in cache.";
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} else {
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status.innerHTML = "Local storage not supported. Try a different browser.";
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}
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}
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} |