JavaScript continue label scope - javascript

Map.prototype.updateMap = function (vehicles) {
nextVehicle:
for (var i = 0; i < vehicles.length; i++) {
for (var j = 0; j < this.oldVehicles.length; j++) {
var vehicle = vehicles[i];
var oldVehicle = this.oldVehicles[j];
if (vehicle.registration == oldVehicle.registration) {
oldVehicle.getPosition(function(latLng) {
if (vehicle.latitude != oldVehicle.lat) {
var newPos = new plugin.google.maps.LatLng(vehicle.latitude, vehicle.longitude);
oldVehicle.setPosition(newPos);
}
continue nextVehicle;
});
}
}
}
};
The code above does not work. I have a feeling this is to do with scope, I can't reach the nextVehicle label from inside the oldVehicle.getPosition method. How can I get around this?

Separate the matching logic from the update logic.
Map.prototype.updateMap = function (vehicles) {
// Only need to look up array lengths once
var vehiclesLength = vehicles.length,
oldVehiclesLength = this.oldVehicles.length;
for (var i = 0; i < vehiclesLength; i++) {
var vehicle = vehicles[i];
var oldVehicle = null;
// Find oldVehicle
for (var j = 0; j < oldVehiclesLength; j++) {
if (vehicle.registration == oldVehicle[j].registration) {
oldVehicle = oldVehicles[j];
break;
}
}
// Check for update if found
if (oldVehicle){
// Create closure for async callbacks
(function(oldV, lat,lng){
oldV.getPosition(function(latLng) {
if (lat != oldV.lat) {
var newPos = new plugin.google.maps.LatLng(lat,lng);
oldV.setPosition(newPos);
}
});
})(oldVehicle, vehicle.latitude, vehicle.longitude);
}
}
};

Just move the continue nextVehicle; line from inside the callback to immediately following the call to oldVehicle.getPosition(...):
Map.prototype.updateMap = function (vehicles) {
nextVehicle:
for (var i = 0; i < vehicles.length; i++) {
for (var j = 0; j < this.oldVehicles.length; j++) {
var vehicle = vehicles[i];
var oldVehicle = this.oldVehicles[j];
if (vehicle.registration == oldVehicle.registration) {
oldVehicle.getPosition(function(latLng) {
if (vehicle.latitude != oldVehicle.lat) {
var newPos = new plugin.google.maps.LatLng(vehicle.latitude, vehicle.longitude);
oldVehicle.setPosition(newPos);
}
});
continue nextVehicle;
}
}
}
};
This assumes the call to getPosition is a synchronous operation.
Edit:
Now if getPosition is asynchronous, you will need to use an asynchronous loop:
Something along this line might do the trick:
Map.prototype.updateMap = function (vehicles) {
var i = 0, j = -1, self = this;
var updatePosition = function() {
j++;
if (j == self.oldVehicles.length) {
j = 0;
i++;
}
if (i === vehicles.length) {
return; // We're done
}
var vehicle = vehicles[i];
var oldVehicle = self.oldVehicles[j];
if (vehicle.registration !== oldVehicle.registration) {
updatePosition();
}
else {
oldVehicle.getPosition(function(latLng) {
if (vehicle.latitude != oldVehicle.lat) {
var newPos = new plugin.google.maps.LatLng(vehicle.latitude, vehicle.longitude);
oldVehicle.setPosition(newPos);
updatePosition();
}
});
}
};
updatePosition();
};

Related

How to get variable data by id

Recently i have used code in project that is still working it it http://kreditka.testovi-site.pw. But when i tried to reuse javascript the default rules js got broken and i got an error in console explaining that varibale cannot be found. Is it somehow related that sme o the code is not resusable and each line should be rewritten one by one for defferent projects?
(function () {
console.log("()");
"use strict";
var polosa = document.querySelector("#polosa");
alert(polosa);
var x = document.querySelectorAll("#slide1");
var o;
for (o = 0; o < x.length; o++) {
x[o].style.left = o*300+"px";
}
var x = document.querySelectorAll("#slide");
var a;
for (a = 0; a < x.length; a++) {
x[a].style.left = a*300+"px";
}
var doc = document.querySelectorAll('.btn-click');
for (var i = 0; i < doc.length; i++) {
doc[i].addEventListener("click", highlightThis, true);
}
var doc1 = document.querySelectorAll('.btn1-click');
for (var j = 0; j < doc.length; j++) {
doc1[j].addEventListener("click", highlightThis1, true);
}
var polosa = document.querySelector('#polosa');
polosa.style.left = '0px';
var left = 0;
var sliderItem = document.querySelector('#slide');
function highlightThis(event) {
console.log("highlightThis");
var currentActiveButton = document.querySelector(".btn-click.btn-slide-active");
currentActiveButton.classList.toggle("btn-slide-active");
event.target.classList.toggle("btn-slide-active");
console.log(event.target.dataset.value);
shiftSlide({
prev: currentActiveButton.dataset.value,
next: event.target.dataset.value
});
}
function highlightThis1(event) {
console.log("highlightThis1");
var currentActiveButton1 = document.querySelector(".btn1-click.btn-slide-active");
currentActiveButton1.classList.toggle("btn-slide-active");
event.target.classList.toggle("btn-slide-active");
console.log(event.target.dataset.value);
shiftSlide1({
prev: currentActiveButton1.dataset.value,
next: event.target.dataset.value
});
}
function shiftSlide(obj) {
var polosa = document.querySelector('#polosa');
console.log("shiftSlide");
var currentSliderPosition = parseInt(polosa.style.left);
if (obj.prev === obj.next) {
return
} else {
var left = (obj.prev - obj.next) * 300;
polosa.style.left = currentSliderPosition + left + "px";
}
}
function shiftSlide1(obj) {
var polosa = document.querySelector('#polosa1');
console.log("shiftSlide");
var currentSliderPosition = parseInt(polosa1.style.left);
if (obj.prev === obj.next) {
return
} else {
var left = (obj.prev - obj.next) * 300;
polosa1.style.left = currentSliderPosition + left + "px";
}
}
})();

Push to an array in a nested loop is repeating the last value

I am trying to push elements to an array in a nested loop, but only the last item is getting repeated in the final array, where am I going wrong, very new to javascript asynchronous concept.Below is the function in which I push the items to an array.
$scope.showBeList = function(feed) {
if (feed[srcServ.KEY_CONTENT_TEXT]) {
var content = JSON.parse(feed[srcServ.KEY_CONTENT_TEXT])
if (content) {
$scope.beList = {};
for (var key in content) {
var decorationVal;
//reading value from a lokijs collection
var decoration = dataServ[srcServ.CONST_COLLECTION_DECORATION].find({
'name': key
});
if (decoration && decoration.length) {
decorationVal = decoration[0];
if (decorationVal != null) {
var tempObj = JSON.parse(decorationVal.value);
if (tempObj) {
var header = tempObj[key][key + '_HEADER'];
if (header) {
var counter = content[key].length;
var tempItems = [];
for (var j = 0; j < content[key].length; j++) {
(function(j) {
var obj = {};
obj[srcServ.KEY_MAIN_HEADER] = tempObj[key][srcServ.KEY_DESC];
obj[srcServ.KEY_SUB_HEADER] = header[srcServ.KEY_DESC];
obj.id = j;
var itemVal = content[key][j][key + '_HEADER'];
var details = [];
var notes = [];
for (var item in itemVal) {
var val = null;
var found = false;
for (var i = 0; i < header.field.length; i++) {
if (header.field[i].name == item) {
val = header.field[i];
found = true;
break;
}
}
if (found && val != null) {
val[srcServ.KEY_DESC_VALUE] = itemVal[item];
details.push(val);
}
}
obj.details = details;
counter--;
if (counter == 0) {
$scope.showMoreDetails = true;
$scope.beList.beItems = tempItems;
console.log(JSON.stringify($scope.beList));
}
tempItems.push(obj)
})(j);
// $scope.beList.beItems.push(obj);
}
}
}
}
}
}
}
}
}

Repeat function in javascript

Could you please tell me how to make from this 4 functions just 1. Cause they all do one thing, with just one parameter changing all the time.
Also, I need to take the value of each time the function is running and put it into a new variable so I can after calculate it.
function getValue(age)
{
for (var i = 0; i < document.getElementsByName('age').length; i++)
{
if (document.getElementsByName('age')[i].checked)
{
return document.getElementsByName('age')[i].value;
}
}
}
function getBmiValue()
{
for (var i = 0; i < document.getElementsByName('bmi').length; i++)
{
if (document.getElementsByName('bmi')[i].checked)
{
return document.getElementsByName('bmi')[i].value;
}
}
}
function getFamValue()
{
for (var i = 0; i < document.getElementsByName('fam').length; i++)
{
if (document.getElementsByName('fam')[i].checked)
{
return document.getElementsByName('fam')[i].value;
}
}
}
function getDietValue()
{
for (var i = 0; i < document.getElementsByName('diet').length; i++)
{
if (document.getElementsByName('diet')[i].checked)
{
return document.getElementsByName('diet')[i].value;
}
}
}
function getValueByElementName(element_name)
{
for (var i = 0; i < document.getElementsByName(element_name).length; i++)
{
if (document.getElementsByName(element_name)[i].checked)
{
return document.getElementsByName(element_name)[i].value;
}
}
}
Or a little bit optimization:
function getValueByElementName(element_name)
{
var elements = document.getElementsByName(element_name);
for (var i = 0; i < elements.length; i++)
{
if (elements[i].checked)
return elements[i].value;
}
}
function getValue(tagname)
{
for (var i = 0; i < document.getElementsByName(tagname).length; i++)
{
if (document.getElementsByName(tagname)[i].checked)
{
return document.getElementsByName(tagname)[i].value;
}
}
}
Pass your element name as a variable in this function and call it.
Here is an example of what you can do:
function getValue(key) {
// get this once, not on each loop iteration
var elem = document.getElementsByName(key);
// cache the length too, so not to calculate it on each loop iteration
for (var i = 0, len = elem.length; i < len; i++) {
if (elem[i].checked) {
return elem[i].value;
// this will exit the function when it finds the FIRST one.
// Is that what you want?
}
}
}
// you can call above function like this:
getValue('age');
getValue('bmi');
getValue('fam');
getValue('diet');

An interval that calls a function inside an object, which also calls a function inside that object

function airEngineJS (canvasArg, properties) {
this.canvas = (canvasArg == "undefined")? trace("Failed to set up canvas for airEngineJS") : canvasArg;
this.cameras = [];
this.displayObjects = [];
this.hudDisplayObjects = [];
this.fps = (properties == "undefined" || properties.fps == "undefined")? 30 : properties.fps;
if (properties == "undefined" || properties.autoinit == "undefined" || properties.autoinit == true){
this.keyboard = new keyboardJS();
this.keyboard.init();
this.cameras.push(new airCameraJS(this));
}
this.enterframe = setInterval(this.intervalCaller, 1000/this.fps);
trace("A new airEngineJS has been created");
}
airEngineJS.prototype = {
intervalCaller : function () {
this.mainLoop();
},
logic : function () {
for (var i = 0; i < this.displayObjects.length; ++i){
this.displayObjects[i].logic();
}
for (var j = 0; j < this.cameras.length; ++j){
this.cameras[j].logic();
}
},
render : function () {
for (var i = 0; i < this.cameras.length; ++i){
for (var j = 0; j < this.displayObjects.length; ++j){
this.displayObjects[j].renderOn(this.cameras[i]);
}
}
for (var i = 0; i < this.hudDisplayObjects.length; ++i){
this.hudDisplayObjects[i].renderOn(this.canvas);
}
},
mainLoop : function () {
this.logic();
this.render();
}
}
The interval [this.enterframe = setInterval(this.intervalCaller, 1000/this.fps);] calls correctly (this.intervalCaller), but this tries to call (this.mainLoop()) in the DOM.
Any suggestions about how should I do it? :(
You can close over the actual function call like this:
var self = this;
this.enterframe = setInterval(function() {
self.intervalCaller();
}, 1000/this.fps);
It first creates a reference to the new instance which is then used inside the closure passed to setInterval.

How to check the object property in javascript

I have an array like below
var colorArray = ["#a", "#b", "#c", "#d", "#e"];
From this I will generate a map like this
function initilizeColorMap(){
for(var i = 0 ;i <colorArray.length ;i++){
colorTrackingMap[i] = {value: colorArray [i],state:"unused"};
}
}
Hopw i can iterate through the map when i need a color (next color from the map ) by checking the state in javascript..?
You can have a method that will return the next color. Check out this jsfiddle : http://jsfiddle.net/QYWDb/
var colorArray = ["#a", "#b", "#c", "#d", "#e"];
var colorTrackingMap = [];
var currentIndex = -1;
for(var i = 0 ;i <colorArray.length ;i++){
colorTrackingMap[i] = {value: colorArray [i],state:"unused"};
}
function getNextColor() {
if (currentIndex > colorTrackingMap.length)
currentIndex = 0;
else
currentIndex++;
while ( colorTrackingMap[currentIndex] !== undefined &&
colorTrackingMap[currentIndex].state !== "unused" ) {
currentIndex++;
}
if ( colorTrackingMap[currentIndex] )
return colorTrackingMap[currentIndex].value;
else
return "No color available";
}
If you need color according to given index you don't have to iterate, use such code:
var currentIndex = 0;
function Next() {
var tracking = colorTrackingMap[currentIndex];
alert("color: " + tracking.value + ", state: " + tracking.state);
currentIndex++;
if (currentIndex >= colorTrackingMap.length)
currentIndex = 0;
}
Live test case.
If you mean searching the array for item with specific value, just use ordinary loop:
function Find() {
var color = document.getElementById("color").value;
var state = "";
for (var i = 0; i < colorTrackingMap.length; i++) {
if (colorTrackingMap[i].value.toLowerCase() === color) {
state = colorTrackingMap[i].state;
break;
}
}
if (state.length == 0) {
alert("color isn't mapped");
} else {
alert("state: " + state);
}
}
You can also pass the color as function argument, this is just for sake of example.
Updated test case.
You could use something like this:
var ColourMap = function (arr) {
var _map = [],
out = [],
i,
len;
// Set up the colour map straight away
for (i = 0, len = arr.length; i < len; i++) {
_map.push({
value: arr[i],
state: "unused"
});
}
return {
get_next: function () {
var i,
len,
next;
for (i = 0, len = _map.length; i < len; i++) {
if (_map[i].state === "unused") {
next = _map[i];
break;
}
}
return next;
}
}
};
And then use something like:
var m = new ColourMap(["#a", "#b", "#c", "#d", "#e"]);
m.get_next(); // get the next available element
Here's a working example.

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