/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
var gMapCanvas, gMapContext, gTrackCanvas, gTrackContext, gGeolocation;
var gDebug = false;
var gTileSize = 256;
var gMaxZoom = 18; // The minimum is 0.
var gMinTrackAccuracy = 1000; // meters
var gTrackWidth = 2; // pixels
var gTrackColor = "#FF0000";
var gCurLocSize = 6; // pixels
var gCurLocColor = "#A00000";
var gMapStyles = {
// OSM tile usage policy: http://wiki.openstreetmap.org/wiki/Tile_usage_policy
// Find some more OSM ones at http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Tile_servers
osm_mapnik:
{name: "OpenStreetMap (Mapnik)",
url: "http://tile.openstreetmap.org/{z}/{x}/{y}.png",
copyright: 'Map data and imagery © OpenStreetMap contributors, ODbL/CC-BY-SA'},
osm_cyclemap:
{name: "Cycle Map (OSM)",
url: "http://[a-c].tile.opencyclemap.org/cycle/{z}/{x}/{y}.png",
copyright: 'Map data and imagery © OpenStreetMap contributors, ODbL/CC-BY-SA'},
osm_transmap:
{name: "Transport Map (OSM)",
url: "http://[a-c].tile2.opencyclemap.org/transport/{z}/{x}/{y}.png",
copyright: 'Map data and imagery © OpenStreetMap contributors, ODbL/CC-BY-SA'},
mapquest_open:
{name: "MapQuest OSM",
url: "http://otile[1-4].mqcdn.com/tiles/1.0.0/osm/{z}/{x}/{y}.png",
copyright: 'Map data © OpenStreetMap and contributors (ODbL/CC-BY-SA), tiles Courtesy of MapQuest.'},
mapquest_aerial:
{name: "MapQuest Open Aerial",
url: "http://oatile[1-4].mqcdn.com/tiles/1.0.0/sat/{z}/{x}/{y}.jpg",
copyright: 'Tiles Courtesy of MapQuest, portions Courtesy NASA/JPL-Caltech and U.S. Depart. of Agriculture, Farm Service Agency.'},
opengeoserver_arial:
{name: "OpenGeoServer Aerial",
url: "http://services.opengeoserver.org/tiles/1.0.0/globe.aerial_EPSG3857/{z}/{x}/{y}.png?origin=nw",
copyright: 'Tiles by OpenGeoServer.org, CC-BY 3.0 AT.'},
google_map:
{name: "Google Maps",
url: " http://mt1.google.com/vt/x={x}&y={y}&z={z}",
copyright: 'Map data and imagery © Google'},
};
var gActiveMap = "osm_mapnik";
var gPos = {x: 35630000.0, // Current position in the map in pixels at the maximum zoom level (18)
y: 23670000.0, // The range is 0-67108864 (2^gMaxZoom * gTileSize)
z: 5}; // This could be fractional if supported being between zoom levels.
var gLastMouseX = 0;
var gLastMouseY = 0;
var gZoomFactor;
// Used as an associative array.
// The keys have to be strings, ours will be "xindex,yindex,zindex" e.g. "13,245,12".
var gTiles = {};
var gLoadingTile;
var gMapPrefsLoaded = false;
var gDragging = false;
var gDragTouchID;
var gGeoWatchID;
var gTrack = [];
var gLastTrackPoint, gLastDrawnPoint;
var gCenterPosition = true;
var gCurPosMapCache;
function initMap() {
gGeolocation = navigator.geolocation;
gMapCanvas = document.getElementById("map");
gMapContext = gMapCanvas.getContext("2d");
gTrackCanvas = document.getElementById("track");
gTrackContext = gTrackCanvas.getContext("2d");
if (!gActiveMap)
gActiveMap = "osm_mapnik";
//gDebug = true;
if (gDebug) {
gGeolocation = geofake;
var hiddenList = document.getElementsByClassName("debugHide");
// last to first - list of elements with that class is changing!
for (var i = hiddenList.length - 1; i >= 0; i--) {
hiddenList[i].classList.remove("debugHide");
}
}
var loopCnt = 0;
var getPersistentPrefs = function() {
if (mainDB) {
gWaitCounter++;
gPrefs.get("position", function(aValue) {
if (aValue) {
gPos = aValue;
gWaitCounter--;
}
});
gWaitCounter++;
gPrefs.get("center_map", function(aValue) {
if (aValue === undefined)
document.getElementById("centerCheckbox").checked = true;
else
document.getElementById("centerCheckbox").checked = aValue;
setCentering(document.getElementById("centerCheckbox"));
gWaitCounter--;
});
gWaitCounter++;
gPrefs.get("tracking_enabled", function(aValue) {
if (aValue === undefined)
document.getElementById("trackCheckbox").checked = true;
else
document.getElementById("trackCheckbox").checked = aValue;
gWaitCounter--;
});
gWaitCounter++;
gTrackStore.getList(function(aTPoints) {
if (gDebug)
document.getElementById("debug").textContent = aTPoints.length + " points loaded.";
if (aTPoints.length) {
gTrack = aTPoints;
}
gWaitCounter--;
});
}
else
setTimeout(getPersistentPrefs, 100);
loopCnt++;
if (loopCnt > 50) {
document.getElementById("debug").textContent = "Loading prefs failed.";
}
};
getPersistentPrefs();
gTrackCanvas.addEventListener("mouseup", mapEvHandler, false);
gTrackCanvas.addEventListener("mousemove", mapEvHandler, false);
gTrackCanvas.addEventListener("mousedown", mapEvHandler, false);
gTrackCanvas.addEventListener("mouseout", mapEvHandler, false);
gTrackCanvas.addEventListener("touchstart", mapEvHandler, false);
gTrackCanvas.addEventListener("touchmove", mapEvHandler, false);
gTrackCanvas.addEventListener("touchend", mapEvHandler, false);
gTrackCanvas.addEventListener("touchcancel", mapEvHandler, false);
gTrackCanvas.addEventListener("touchleave", mapEvHandler, false);
// XXX deprecated? see https://groups.google.com/forum/?fromgroups#!topic/mozilla.dev.planning/kuhrORubaRY[1-25]
gTrackCanvas.addEventListener("DOMMouseScroll", mapEvHandler, false);
gTrackCanvas.addEventListener("mousewheel", mapEvHandler, false);
document.getElementById("copyright").innerHTML =
gMapStyles[gActiveMap].copyright;
gLoadingTile = new Image();
gLoadingTile.src = "style/loading.png";
gWaitCounter++;
gLoadingTile.onload = function() { gWaitCounter--; };
}
function resizeAndDraw() {
var viewportWidth = Math.min(window.innerWidth, window.outerWidth);
var viewportHeight = Math.min(window.innerHeight, window.outerHeight);
gMapCanvas.width = viewportWidth;
gMapCanvas.height = viewportHeight;
gTrackCanvas.width = viewportWidth;
gTrackCanvas.height = viewportHeight;
drawMap();
showUI();
}
function zoomIn() {
if (gPos.z < gMaxZoom) {
gPos.z++;
drawMap();
}
}
function zoomOut() {
if (gPos.z > 0) {
gPos.z--;
drawMap();
}
}
function gps2xy(aLatitude, aLongitude) {
var maxZoomFactor = Math.pow(2, gMaxZoom) * gTileSize;
var convLat = aLatitude * Math.PI / 180;
var rawY = (1 - Math.log(Math.tan(convLat) +
1 / Math.cos(convLat)) / Math.PI) / 2 * maxZoomFactor;
var rawX = (aLongitude + 180) / 360 * maxZoomFactor;
return {x: Math.round(rawX),
y: Math.round(rawY)};
}
function xy2gps(aX, aY) {
var maxZoomFactor = Math.pow(2, gMaxZoom) * gTileSize;
var n = Math.PI - 2 * Math.PI * aY / maxZoomFactor;
return {latitude: 180 / Math.PI *
Math.atan(0.5 * (Math.exp(n) - Math.exp(-n))),
longitude: aX / maxZoomFactor * 360 - 180};
}
function setMapStyle() {
var mapSel = document.getElementById("mapSelector");
if (mapSel.selectedIndex >= 0 && gActiveMap != mapSel.value) {
gActiveMap = mapSel.value;
gTiles = {};
document.getElementById("copyright").innerHTML =
gMapStyles[gActiveMap].copyright;
showUI();
drawMap();
}
}
// A sane mod function that works for negative numbers.
// Returns a % b.
function mod(a, b) {
return ((a % b) + b) % b;
}
function normalizeCoords(aCoords) {
var zoomFactor = Math.pow(2, aCoords.z);
return {x: mod(aCoords.x, zoomFactor),
y: mod(aCoords.y, zoomFactor),
z: aCoords.z};
}
// Returns true if the tile is outside the current view.
function isOutsideWindow(t) {
var pos = decodeIndex(t);
var zoomFactor = Math.pow(2, gMaxZoom - pos.z);
var wid = gMapCanvas.width * zoomFactor;
var ht = gMapCanvas.height * zoomFactor;
pos.x *= zoomFactor;
pos.y *= zoomFactor;
var sz = gTileSize * zoomFactor;
if (pos.x > gPos.x + wid / 2 || pos.y > gPos.y + ht / 2 ||
pos.x + sz < gPos.x - wid / 2 || pos.y - sz < gPos.y - ht / 2)
return true;
return false;
}
function encodeIndex(x, y, z) {
var norm = normalizeCoords({x: x, y: y, z: z});
return norm.x + "," + norm.y + "," + norm.z;
}
function decodeIndex(encodedIdx) {
var ind = encodedIdx.split(",", 3);
return {x: ind[0], y: ind[1], z: ind[2]};
}
function drawMap() {
// Go through all the currently loaded tiles. If we don't want any of them remove them.
// for (t in gTiles) {
// if (isOutsideWindow(t))
// delete gTiles[t];
// }
document.getElementById("zoomLevel").textContent = gPos.z;
gZoomFactor = Math.pow(2, gMaxZoom - gPos.z);
var wid = gMapCanvas.width * gZoomFactor; // Width in level 18 pixels.
var ht = gMapCanvas.height * gZoomFactor; // Height in level 18 pixels.
var size = gTileSize * gZoomFactor; // Tile size in level 18 pixels.
var xMin = gPos.x - wid / 2; // Corners of the window in level 18 pixels.
var yMin = gPos.y - ht / 2;
var xMax = gPos.x + wid / 2;
var yMax = gPos.y + ht / 2;
if (gMapPrefsLoaded && mainDB)
gPrefs.set("position", gPos);
// Go through all the tiles we want.
// If any of them aren't loaded or being loaded, do so.
for (var x = Math.floor(xMin / size); x < Math.ceil(xMax / size); x++) {
for (var y = Math.floor(yMin / size); y < Math.ceil(yMax / size); y++) { // slow script warnings on the tablet appear here!
// Round here is **CRUCIAL** otherwise the images are filtered
// and the performance sucks (more than expected).
var xoff = Math.round((x * size - xMin) / gZoomFactor);
var yoff = Math.round((y * size - yMin) / gZoomFactor);
// Draw placeholder, and then initiate loading/drawing of real one.
gMapContext.drawImage(gLoadingTile, xoff, yoff);
gTileService.get(gActiveMap, {x: x, y: y, z: gPos.z}, function(aImage, aStyle, aCoords) {
// Only draw if this applies for the current view.
if ((aStyle == gActiveMap) && (aCoords.z == gPos.z)) {
var ixMin = gPos.x - wid / 2;
var iyMin = gPos.y - ht / 2;
var ixoff = Math.round((aCoords.x * size - ixMin) / gZoomFactor);
var iyoff = Math.round((aCoords.y * size - iyMin) / gZoomFactor);
var URL = window.URL;
var imgURL = URL.createObjectURL(aImage);
var imgObj = new Image();
imgObj.src = imgURL;
gMapContext.drawImage(imgObj, ixoff, iyoff);
URL.revokeObjectURL(imgURL);
}
});
}
}
gLastDrawnPoint = null;
gCurPosMapCache = undefined;
gTrackContext.clearRect(0, 0, gTrackCanvas.width, gTrackCanvas.height);
if (gTrack.length) {
for (var i = 0; i < gTrack.length; i++) {
drawTrackPoint(gTrack[i].coords.latitude, gTrack[i].coords.longitude,
(i + 1 >= gTrack.length));
}
}
}
function drawTrackPoint(aLatitude, aLongitude, lastPoint) {
var trackpoint = gps2xy(aLatitude, aLongitude);
// lastPoint is for optimizing (not actually executing the draw until the last)
trackpoint.optimized = (lastPoint === false);
var mappos = {x: Math.round((trackpoint.x - gPos.x) / gZoomFactor + gMapCanvas.width / 2),
y: Math.round((trackpoint.y - gPos.y) / gZoomFactor + gMapCanvas.height / 2)};
if (!gLastDrawnPoint || !gLastDrawnPoint.optimized) {
gTrackContext.strokeStyle = gTrackColor;
gTrackContext.fillStyle = gTrackContext.strokeStyle;
gTrackContext.lineWidth = gTrackWidth;
gTrackContext.lineCap = "round";
gTrackContext.lineJoin = "round";
}
if (!gLastDrawnPoint || gLastDrawnPoint == trackpoint) {
// This breaks optimiziation, so make sure to close path and reset optimization.
if (gLastDrawnPoint && gLastDrawnPoint.optimized)
gTrackContext.stroke();
gTrackContext.beginPath();
trackpoint.optimized = false;
gTrackContext.arc(mappos.x, mappos.y,
gTrackContext.lineWidth, 0, Math.PI * 2, false);
gTrackContext.fill();
}
else {
if (!gLastDrawnPoint || !gLastDrawnPoint.optimized) {
gTrackContext.beginPath();
gTrackContext.moveTo(Math.round((gLastDrawnPoint.x - gPos.x) / gZoomFactor + gMapCanvas.width / 2),
Math.round((gLastDrawnPoint.y - gPos.y) / gZoomFactor + gMapCanvas.height / 2));
}
gTrackContext.lineTo(mappos.x, mappos.y);
if (!trackpoint.optimized)
gTrackContext.stroke();
}
gLastDrawnPoint = trackpoint;
}
function drawCurrentLocation(trackPoint) {
var locpoint = gps2xy(trackPoint.coords.latitude, trackPoint.coords.longitude);
var circleRadius = Math.round(gCurLocSize / 2);
var mappos = {x: Math.round((locpoint.x - gPos.x) / gZoomFactor + gMapCanvas.width / 2),
y: Math.round((locpoint.y - gPos.y) / gZoomFactor + gMapCanvas.height / 2)};
undrawCurrentLocation();
// Cache overdrawn area.
gCurPosMapCache =
{point: locpoint,
radius: circleRadius,
data: gTrackContext.getImageData(mappos.x - circleRadius,
mappos.y - circleRadius,
circleRadius * 2, circleRadius * 2)};
gTrackContext.strokeStyle = gCurLocColor;
gTrackContext.fillStyle = gTrackContext.strokeStyle;
gTrackContext.beginPath();
gTrackContext.arc(mappos.x, mappos.y,
circleRadius, 0, Math.PI * 2, false);
gTrackContext.fill();
}
function undrawCurrentLocation() {
if (gCurPosMapCache) {
var oldpoint = gCurPosMapCache.point;
var oldmp = {x: Math.round((oldpoint.x - gPos.x) / gZoomFactor + gMapCanvas.width / 2),
y: Math.round((oldpoint.y - gPos.y) / gZoomFactor + gMapCanvas.height / 2)};
gTrackContext.putImageData(gCurPosMapCache.data,
oldmp.x - gCurPosMapCache.radius,
oldmp.y - gCurPosMapCache.radius);
gCurPosMapCache = undefined;
}
}
var mapEvHandler = {
handleEvent: function(aEvent) {
var touchEvent = aEvent.type.indexOf('touch') != -1;
// Bail out on unwanted map moves, but not zoom-changing events.
if (aEvent.type != "DOMMouseScroll" && aEvent.type != "mousewheel") {
// Bail out if this is neither a touch nor left-click.
if (!touchEvent && aEvent.button != 0)
return;
// Bail out if the started touch can't be found.
if (touchEvent && gDragging &&
!aEvent.changedTouches.identifiedTouch(gDragTouchID))
return;
}
var coordObj = touchEvent ?
aEvent.changedTouches.identifiedTouch(gDragTouchID) :
aEvent;
switch (aEvent.type) {
case "mousedown":
case "touchstart":
if (touchEvent) {
gDragTouchID = aEvent.changedTouches.item(0).identifier;
coordObj = aEvent.changedTouches.identifiedTouch(gDragTouchID);
}
var x = coordObj.clientX - gMapCanvas.offsetLeft;
var y = coordObj.clientY - gMapCanvas.offsetTop;
if (touchEvent || aEvent.button === 0) {
gDragging = true;
}
gLastMouseX = x;
gLastMouseY = y;
showUI();
break;
case "mousemove":
case "touchmove":
var x = coordObj.clientX - gMapCanvas.offsetLeft;
var y = coordObj.clientY - gMapCanvas.offsetTop;
if (gDragging === true) {
var dX = x - gLastMouseX;
var dY = y - gLastMouseY;
gPos.x -= dX * gZoomFactor;
gPos.y -= dY * gZoomFactor;
drawMap();
showUI();
}
gLastMouseX = x;
gLastMouseY = y;
break;
case "mouseup":
case "touchend":
gDragging = false;
showUI();
break;
case "mouseout":
case "touchcancel":
case "touchleave":
//gDragging = false;
break;
case "DOMMouseScroll":
case "mousewheel":
var delta = 0;
if (aEvent.wheelDelta) {
delta = aEvent.wheelDelta / 120;
if (window.opera)
delta = -delta;
}
else if (aEvent.detail) {
delta = -aEvent.detail / 3;
}
// Debug output: "coordinates" of the point the mouse was over.
/*
var ptCoord = {x: gPos.x + (x - gMapCanvas.width / 2) * gZoomFactor,
y: gPos.y + (x - gMapCanvas.height / 2) * gZoomFactor};
var gpsCoord = xy2gps(ptCoord.x, ptCoord.y);
var pt2Coord = gps2xy(gpsCoord.latitude, gpsCoord.longitude);
document.getElementById("debug").textContent =
ptCoord.x + "/" + ptCoord.y + " - " +
gpsCoord.latitude + "/" + gpsCoord.longitude + " - " +
pt2Coord.x + "/" + pt2Coord.y;
*/
var newZoomLevel = gPos.z + (delta > 0 ? 1 : -1);
if ((newZoomLevel >= 0) && (newZoomLevel <= gMaxZoom)) {
// Calculate new center of the map - same point stays under the mouse.
// This means that the pixel distance between the old center and point
// must equal the pixel distance of the new center and that point.
var x = coordObj.clientX - gMapCanvas.offsetLeft;
var y = coordObj.clientY - gMapCanvas.offsetTop;
// Zoom factor after this action.
var newZoomFactor = Math.pow(2, gMaxZoom - newZoomLevel);
gPos.x -= (x - gMapCanvas.width / 2) * (newZoomFactor - gZoomFactor);
gPos.y -= (y - gMapCanvas.height / 2) * (newZoomFactor - gZoomFactor);
if (delta > 0)
zoomIn();
else if (delta < 0)
zoomOut();
}
break;
}
}
};
var geofake = {
tracking: false,
lastPos: {x: undefined, y: undefined},
watchPosition: function(aSuccessCallback, aErrorCallback, aPrefObject) {
this.tracking = true;
var watchCall = function() {
// calc new position in lat/lon degrees
// 90° on Earth surface are ~10,000 km at the equator,
// so try moving at most 10m at a time
if (geofake.lastPos.x)
geofake.lastPos.x += (Math.random() - .5) * 90 / 1000000
else
geofake.lastPos.x = 48.208174
if (geofake.lastPos.y)
geofake.lastPos.y += (Math.random() - .5) * 90 / 1000000
else
geofake.lastPos.y = 16.373819
aSuccessCallback({timestamp: Date.now(),
coords: {latitude: geofake.lastPos.x,
longitude: geofake.lastPos.y,
accuracy: 20}});
if (geofake.tracking)
setTimeout(watchCall, 1000);
};
setTimeout(watchCall, 1000);
return "foo";
},
clearWatch: function(aID) {
this.tracking = false;
}
}
function setCentering(aCheckbox) {
if (gMapPrefsLoaded && mainDB)
gPrefs.set("center_map", aCheckbox.checked);
gCenterPosition = aCheckbox.checked;
}
function setTracking(aCheckbox) {
if (gMapPrefsLoaded && mainDB)
gPrefs.set("tracking_enabled", aCheckbox.checked);
if (aCheckbox.checked)
startTracking();
else
endTracking();
}
function startTracking() {
if (gGeolocation) {
gGeoWatchID = gGeolocation.watchPosition(
function(position) {
// Coords spec: https://developer.mozilla.org/en/XPCOM_Interface_Reference/NsIDOMGeoPositionCoords
var tPoint = {time: position.timestamp,
coords: {latitude: position.coords.latitude,
longitude: position.coords.longitude,
altitude: position.coords.altitude,
accuracy: position.coords.accuracy,
altitudeAccuracy: position.coords.altitudeAccuracy,
heading: position.coords.heading,
speed: position.coords.speed},
beginSegment: !gLastTrackPoint};
// Only add point to track is accuracy is good enough.
if (tPoint.coords.accuracy < gMinTrackAccuracy) {
gLastTrackPoint = tPoint;
gTrack.push(tPoint);
try { gTrackStore.push(tPoint); } catch(e) {}
var redrawn = false;
if (gCenterPosition) {
var posCoord = gps2xy(position.coords.latitude,
position.coords.longitude);
if (Math.abs(gPos.x - posCoord.x) > gMapCanvas.width * gZoomFactor / 4 ||
Math.abs(gPos.y - posCoord.y) > gMapCanvas.height * gZoomFactor / 4) {
gPos.x = posCoord.x;
gPos.y = posCoord.y;
drawMap(); // This draws the current point as well.
redrawn = true;
}
}
if (!redrawn)
undrawCurrentLocation();
drawTrackPoint(position.coords.latitude, position.coords.longitude, true);
}
drawCurrentLocation(tPoint);
},
function(error) {
// Ignore erros for the moment, but this is good for debugging.
// See https://developer.mozilla.org/en/Using_geolocation#Handling_errors
document.getElementById("debug").textContent = error.message;
},
{enableHighAccuracy: true}
);
}
}
function endTracking() {
if (gGeoWatchID) {
gGeolocation.clearWatch(gGeoWatchID);
}
}
function clearTrack() {
gTrack = [];
gTrackStore.clear();
drawMap();
}
var gTileService = {
objStore: "tilecache",
get: function(aStyle, aCoords, aCallback) {
var norm = normalizeCoords(aCoords);
var dbkey = aStyle + "::" + norm.x + "," + norm.y + "," + norm.z;
this.getDBCache(dbkey, function(aResult, aEvent) {
if (aResult) {
// We did get a cached object.
// TODO: Look at the timestamp and trigger a reload when it's too old.
aCallback(aResult.image, aStyle, aCoords);
}
else {
// Retrieve image from the web and store it in the cache.
var XHR = new XMLHttpRequest();
XHR.open("GET",
gMapStyles[aStyle].url
.replace("{x}", norm.x)
.replace("{y}", norm.y)
.replace("{z}", norm.z)
.replace("[a-c]", String.fromCharCode(97 + Math.floor(Math.random() * 2)))
.replace("[1-4]", 1 + Math.floor(Math.random() * 3)),
true);
XHR.responseType = "blob";
XHR.addEventListener("load", function () {
if (XHR.status === 200) {
var blob = XHR.response;
gTileService.setDBCache(dbkey, {image: blob, timestamp: Date.now()});
aCallback(blob, aStyle, aCoords);
}
}, false);
XHR.send();
}
});
},
getDBCache: function(aKey, aCallback) {
if (!mainDB)
return;
var transaction = mainDB.transaction([this.objStore]);
var request = transaction.objectStore(this.objStore).get(aKey);
request.onsuccess = function(event) {
aCallback(request.result, event);
};
request.onerror = function(event) {
// Errors can be handled here.
aCallback(undefined, event);
};
},
setDBCache: function(aKey, aValue, aCallback) {
if (!mainDB)
return;
var success = false;
var transaction = mainDB.transaction([this.objStore], "readwrite");
var objStore = transaction.objectStore(this.objStore);
var request = objStore.put(aValue, aKey);
request.onsuccess = function(event) {
success = true;
if (aCallback)
aCallback(success, event);
};
request.onerror = function(event) {
// Errors can be handled here.
if (aCallback)
aCallback(success, event);
};
},
unsetDBCache: function(aKey, aCallback) {
if (!mainDB)
return;
var success = false;
var transaction = mainDB.transaction([this.objStore], "readwrite");
var request = transaction.objectStore(this.objStore).delete(aKey);
request.onsuccess = function(event) {
success = true;
if (aCallback)
aCallback(success, event);
};
request.onerror = function(event) {
// Errors can be handled here.
if (aCallback)
aCallback(success, event);
}
}
};