X-Git-Url: https://git-public.kairo.at/?p=lantea.git;a=blobdiff_plain;f=js%2Fmap.js;h=3cc00c5384c6fd6b97bbf00496a5d91404819f6b;hp=b35a89cce8d62e3946ba670daf56f1998fda5004;hb=6ddefbf98ebff13592de1d87a3bfc2796ac06d84;hpb=4b1d0915c90afdb6ca77be1dc721cc4ccec5cf0c;ds=sidebyside diff --git a/js/map.js b/js/map.js index b35a89c..3cc00c5 100644 --- a/js/map.js +++ b/js/map.js @@ -35,7 +35,7 @@ var gMapStyles = { 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", + url: "http://otile[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", @@ -56,9 +56,6 @@ 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; @@ -92,88 +89,119 @@ function initMap() { } } - 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."; + console.log("map vars set, loading prefs..."); + loadPrefs(); +} + +function loadPrefs(aEvent) { + if (aEvent && aEvent.type == "prefs-step") { + console.log("wait: " + gWaitCounter); + if (gWaitCounter == 0) { + gAction.removeEventListener(aEvent.type, loadPrefs, false); + gMapPrefsLoaded = true; + console.log("prefs loaded."); + + 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); + + gTrackCanvas.addEventListener("wheel", mapEvHandler, false); + + document.getElementById("body").addEventListener("keydown", mapEvHandler, false); + + document.getElementById("copyright").innerHTML = + gMapStyles[gActiveMap].copyright; + + gLoadingTile = new Image(); + gLoadingTile.src = "style/loading.png"; + gLoadingTile.onload = function() { + var throwEv = new CustomEvent("mapinit-done"); + gAction.dispatchEvent(throwEv); + }; } - }; - 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--; }; + } + else { + if (aEvent) + gAction.removeEventListener(aEvent.type, loadPrefs, false); + gAction.addEventListener("prefs-step", loadPrefs, false); + gWaitCounter++; + gPrefs.get("position", function(aValue) { + if (aValue) { + gPos = aValue; + } + gWaitCounter--; + var throwEv = new CustomEvent("prefs-step"); + gAction.dispatchEvent(throwEv); + }); + 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--; + var throwEv = new CustomEvent("prefs-step"); + gAction.dispatchEvent(throwEv); + }); + gWaitCounter++; + gPrefs.get("tracking_enabled", function(aValue) { + if (aValue === undefined) + document.getElementById("trackCheckbox").checked = true; + else + document.getElementById("trackCheckbox").checked = aValue; + gWaitCounter--; + var throwEv = new CustomEvent("prefs-step"); + gAction.dispatchEvent(throwEv); + }); + gWaitCounter++; + var trackLoadStarted = false; + gTrackStore.getListStepped(function(aTPoint) { + if (aTPoint) { + // Add in front and return new length. + var tracklen = gTrack.unshift(aTPoint); + // Redraw track every 100 values (initial paint will do first anyhow). + if (tracklen % 100 == 0) + drawTrack(); + } + else { + // Last point received. + drawTrack(); + } + if (!trackLoadStarted) { + // We have the most recent point, if present, rest will load async. + trackLoadStarted = true; + gWaitCounter--; + var throwEv = new CustomEvent("prefs-step"); + gAction.dispatchEvent(throwEv); + } + }); + } } 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(); + if (gMapCanvas && gTrackCanvas) { + gMapCanvas.width = viewportWidth; + gMapCanvas.height = viewportHeight; + gTrackCanvas.width = viewportWidth; + gTrackCanvas.height = viewportHeight; + drawMap(); + showUI(); + } } +// Using scale(x, y) together with drawing old data on scaled canvas would be an improvement for zooming. +// See https://developer.mozilla.org/en-US/docs/Canvas_tutorial/Transformations#Scaling + function zoomIn() { if (gPos.z < gMaxZoom) { gPos.z++; @@ -188,6 +216,14 @@ function zoomOut() { } } +function zoomTo(aTargetLevel) { + aTargetLevel = parseInt(aTargetLevel); + if (aTargetLevel >= 0 && aTargetLevel <= gMaxZoom) { + gPos.z = aTargetLevel; + drawMap(); + } +} + function gps2xy(aLatitude, aLongitude) { var maxZoomFactor = Math.pow(2, gMaxZoom) * gTileSize; var convLat = aLatitude * Math.PI / 180; @@ -210,7 +246,6 @@ 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(); @@ -224,21 +259,11 @@ function mod(a, b) { return ((a % b) + b) % b; } -function normaliseIndices(x, y, z) { - var zoomFactor = Math.pow(2, z); - return {x: mod(x, zoomFactor), - y: mod(y, zoomFactor), - z: z}; -} - -function tileURL(x, y, z) { - var norm = normaliseIndices(x, y, z); - return gMapStyles[gActiveMap].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)); +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. @@ -260,7 +285,7 @@ function isOutsideWindow(t) { } function encodeIndex(x, y, z) { - var norm = normaliseIndices(x, y, z); + var norm = normalizeCoords({x: x, y: y, z: z}); return norm.x + "," + norm.y + "," + norm.z; } @@ -269,12 +294,17 @@ function decodeIndex(encodedIdx) { 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]; - // } +function drawMap(aPixels, aOverdraw) { + // aPixels is an object with left/right/top/bottom members telling how many + // pixels on the borders should actually be drawn. + // aOverdraw is a bool that tells if we should draw placeholders or draw + // straight over the existing content. + if (!aPixels) + aPixels = {left: gMapCanvas.width, right: gMapCanvas.width, + top: gMapCanvas.height, bottom: gMapCanvas.height}; + if (!aOverdraw) + aOverdraw = false; + document.getElementById("zoomLevel").textContent = gPos.z; gZoomFactor = Math.pow(2, gMaxZoom - gPos.z); var wid = gMapCanvas.width * gZoomFactor; // Width in level 18 pixels. @@ -289,42 +319,57 @@ function drawMap() { 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. + var tiles = {left: Math.ceil((xMin + aPixels.left * gZoomFactor) / size) - + (aPixels.left ? 0 : 1), + right: Math.floor((xMax - aPixels.right * gZoomFactor) / size) - + (aPixels.right ? 1 : 0), + top: Math.ceil((yMin + aPixels.top * gZoomFactor) / size) - + (aPixels.top ? 0 : 1), + bottom: Math.floor((yMax - aPixels.bottom * gZoomFactor) / size) - + (aPixels.bottom ? 1 : 0)}; + + // Go through all the tiles in the map, find out if to draw them and 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); - var tileKey = encodeIndex(x, y, gPos.z); - if (gTiles[tileKey] && gTiles[tileKey].complete) { - gMapContext.drawImage(gTiles[tileKey], xoff, yoff); - } - else { - // Draw placeholder, and then initiate loading/drawing of real one. - gMapContext.drawImage(gLoadingTile, xoff, yoff); - if (!gTiles[tileKey]) { - gTiles[tileKey] = new Image(); - // Use alt field to communicate info to .onload. - gTiles[tileKey].alt = gPos.z + ":" + xoff + ":" + yoff; - gTiles[tileKey].src = tileURL(x, y, gPos.z); - gTiles[tileKey].onload = function() { - var tdata = this.alt.split(":", 3); - // Draw the tile if we're still looking at the same zoom. - if (tdata[0] == gPos.z) { - gMapContext.drawImage(this, tdata[1], tdata[2]); + // Only go to the drawing step if we need to draw this tile. + if (x < tiles.left || x > tiles.right || + y < tiles.top || y > tiles.bottom) { + // 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 tile unless we overdraw. + if (!aOverdraw && + (x < tiles.left -1 || x > tiles.right + 1 || + y < tiles.top -1 || y > tiles.bottom + 1)) + gMapContext.drawImage(gLoadingTile, xoff, yoff); + + // Initiate loading/drawing of the actual tile. + 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; + imgObj.onload = function() { + gMapContext.drawImage(imgObj, ixoff, iyoff); + URL.revokeObjectURL(imgURL); } - this.alt = ""; } - } - else { - // Update position to draw this image to when loaded. - gTiles[tileKey].alt = gPos.z + ":" + xoff + ":" + yoff; - } + }); } } } + drawTrack(); +} + +function drawTrack() { gLastDrawnPoint = null; gCurPosMapCache = undefined; gTrackContext.clearRect(0, 0, gTrackCanvas.width, gTrackCanvas.height); @@ -413,8 +458,12 @@ 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 the event is happening on an input. + if (aEvent.target.tagName.toLowerCase() == "input") + return; + + // Bail out on unwanted map moves, but not zoom or keyboard events. + if (aEvent.type.indexOf("mouse") === 0 || aEvent.type.indexOf("touch") === 0) { // Bail out if this is neither a touch nor left-click. if (!touchEvent && aEvent.button != 0) return; @@ -455,7 +504,20 @@ var mapEvHandler = { var dY = y - gLastMouseY; gPos.x -= dX * gZoomFactor; gPos.y -= dY * gZoomFactor; - drawMap(); + if (true) { // use optimized path + var mapData = gMapContext.getImageData(0, 0, + gMapCanvas.width, + gMapCanvas.height); + gMapContext.clearRect(0, 0, gMapCanvas.width, gMapCanvas.height); + gMapContext.putImageData(mapData, dX, dY); + drawMap({left: (dX > 0) ? dX : 0, + right: (dX < 0) ? -dX : 0, + top: (dY > 0) ? dY : 0, + bottom: (dY < 0) ? -dY : 0}); + } + else { + drawMap(false, true); + } showUI(); } gLastMouseX = x; @@ -471,17 +533,13 @@ var mapEvHandler = { 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; - } + case "wheel": + // If we'd want pixels, we'd need to calc up using aEvent.deltaMode. + // See https://developer.mozilla.org/en-US/docs/Mozilla_event_reference/wheel + + // Only accept (non-null) deltaY values + if (!aEvent.deltaY) + break; // Debug output: "coordinates" of the point the mouse was over. /* @@ -489,13 +547,12 @@ var mapEvHandler = { 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; + console.log(ptCoord.x + "/" + ptCoord.y + " - " + + gpsCoord.latitude + "/" + gpsCoord.longitude + " - " + + pt2Coord.x + "/" + pt2Coord.y); */ - var newZoomLevel = gPos.z + (delta > 0 ? 1 : -1); + var newZoomLevel = gPos.z + (aEvent.deltaY < 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 @@ -508,12 +565,94 @@ var mapEvHandler = { gPos.x -= (x - gMapCanvas.width / 2) * (newZoomFactor - gZoomFactor); gPos.y -= (y - gMapCanvas.height / 2) * (newZoomFactor - gZoomFactor); - if (delta > 0) + if (aEvent.deltaY < 0) zoomIn(); - else if (delta < 0) + else zoomOut(); } break; + case "keydown": + // Allow keyboard control to move and zoom the map. + // Should use aEvent.key instead of aEvent.which but needs bug 680830. + // See https://developer.mozilla.org/en-US/docs/DOM/Mozilla_event_reference/keydown + var dX = 0; + var dY = 0; + switch (aEvent.which) { + case 39: // right + dX = -gTileSize / 2; + break; + case 37: // left + dX = gTileSize / 2; + break; + case 38: // up + dY = gTileSize / 2; + break; + case 40: // down + dY = -gTileSize / 2; + break; + case 87: // w + case 107: // + (numpad) + case 171: // + (normal key) + zoomIn(); + break; + case 83: // s + case 109: // - (numpad) + case 173: // - (normal key) + zoomOut(); + break; + case 48: // 0 + case 49: // 1 + case 50: // 2 + case 51: // 3 + case 52: // 4 + case 53: // 5 + case 54: // 6 + case 55: // 7 + case 56: // 8 + zoomTo(aEvent.which - 38); + break; + case 57: // 9 + zoomTo(9); + break; + case 96: // 0 (numpad) + case 97: // 1 (numpad) + case 98: // 2 (numpad) + case 99: // 3 (numpad) + case 100: // 4 (numpad) + case 101: // 5 (numpad) + case 102: // 6 (numpad) + case 103: // 7 (numpad) + case 104: // 8 (numpad) + zoomTo(aEvent.which - 86); + break; + case 105: // 9 (numpad) + zoomTo(9); + break; + default: // not supported + console.log("key not supported: " + aEvent.which); + break; + } + + // Move if needed. + if (dX || dY) { + gPos.x -= dX * gZoomFactor; + gPos.y -= dY * gZoomFactor; + if (true) { // use optimized path + var mapData = gMapContext.getImageData(0, 0, + gMapCanvas.width, + gMapCanvas.height); + gMapContext.clearRect(0, 0, gMapCanvas.width, gMapCanvas.height); + gMapContext.putImageData(mapData, dX, dY); + drawMap({left: (dX > 0) ? dX : 0, + right: (dX < 0) ? -dX : 0, + top: (dY > 0) ? dY : 0, + bottom: (dY < 0) ? -dY : 0}); + } + else { + drawMap(false, true); + } + } + break; } } }; @@ -567,8 +706,14 @@ function setTracking(aCheckbox) { function startTracking() { if (gGeolocation) { + gActionLabel.textContent = "Establishing Position"; + gAction.style.display = "block"; gGeoWatchID = gGeolocation.watchPosition( function(position) { + if (gActionLabel.textContent) { + gActionLabel.textContent = ""; + gAction.style.display = "none"; + } // Coords spec: https://developer.mozilla.org/en/XPCOM_Interface_Reference/NsIDOMGeoPositionCoords var tPoint = {time: position.timestamp, coords: {latitude: position.coords.latitude, @@ -605,7 +750,8 @@ function startTracking() { 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; + if (gDebug) + console.log(error.message); }, {enableHighAccuracy: true} ); @@ -613,6 +759,10 @@ function startTracking() { } function endTracking() { + if (gActionLabel.textContent) { + gActionLabel.textContent = ""; + gAction.style.display = "none"; + } if (gGeoWatchID) { gGeolocation.clearWatch(gGeoWatchID); } @@ -621,5 +771,116 @@ function endTracking() { function clearTrack() { gTrack = []; gTrackStore.clear(); - drawMap(); + drawTrack(); } + +var gTileService = { + objStore: "tilecache", + + ageLimit: 14 * 86400 * 1000, // 2 weeks (in ms) + + 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. + aCallback(aResult.image, aStyle, aCoords); + // Look at the timestamp and return if it's not too old. + if (aResult.timestamp + gTileService.ageLimit > Date.now()) + return; + // Reload cached tile otherwise. + var oldDate = new Date(aResult.timestamp); + console.log("reload cached tile: " + dbkey + " - " + oldDate.toUTCString()); + } + // 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; + aCallback(blob, aStyle, aCoords); + gTileService.setDBCache(dbkey, {image: blob, timestamp: Date.now()}); + } + }, 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); + } + }, + + clearDB: function(aCallback) { + if (!mainDB) + return; + var success = false; + var transaction = mainDB.transaction([this.objStore], "readwrite"); + var request = transaction.objectStore(this.objStore).clear(); + 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); + } + } +};