Can someone explain why my if statement doesn't work in the displayStorageSizeToConvert() function? Please and thank you!
var userInput = document.getElementById("userInput");
var kbButton = document.getElementById("k");
var mbButton = document.getElementById("mbButton");
var KilobyteDisplay = document.getElementById('KilobyteDisplay');
var megabyteDisplay = document.getElementById('megabyteDisplay');
var submitButton = document.getElementById('submit');
function displayStorageSizeToConvert() {
if (kbButton.clicked === true) {
return convertFrom.innerHTML = "KB";
}
else {
return convertFrom.innerHTML = "MB";
}
}
function convertStorageSizeFrom() {
if(convertFrom.value === "KB") {
KilobyteDisplay.innerHTML = userInput.value + " KB";
megabyteDisplay.innerHTML = userInput.value / 1000 + " MB";
}
}
It doesn't look like you're invoking your function anywhere.
Also, you should attach this function to a click handler:
function displayInKB() {
convertFrom.innerHTML = "KB";
}
function displayInMb() {
convertFrom.innerHTML = "MB";
}
kbButton.addEventListener('click', displayInKb);
mbButton.addEventListener('click', displayInMb)
You are not currently ever calling/triggering displayStorageSizeToConvert().
I think you are wanting to create a listener. You can add it like this:
kbButton.addEventListener('click', () => convertForm.innerHTML = "KB")
Related
I am making a financial report where user choose 2 dates search_date1 and search_date2, and then a monthly report is generated.
I created first a daily report with only one calendar and when it is changed I apply some AJAX script to it and it works correctly:
var myApp = {};
myApp.search_date = "";
document.getElementById('search_date').onchange = function (e) {
if (this.value != myApp.search_date) {
var d = $("#search_date").val();
$.ajax({
...
});
}
}
Now I can't know how to detect if both calendars are changed to apply AJAX script according to their values.
EDIT
Is it correct to do the following:
var myApp = {};
myApp.search_date1 = "";
myApp.search_date2 = "";
document.getElementById('search_date1').onchange = function (e) {
if (this.value != myApp.search_date1) {
var d1 = $("#search_date1").val();
document.getElementById('search_date2').onchange = function (e) {
if (this.value != myApp.search_date2) {
var d2 = $("#search_date2").val();
$.ajax({
...
})
}
});
}
});
try this:
var temp = {
from: null,
to: null
}
document.getElementById('from').onchange = function(e){
temp.from = e.target.value;
goAjax();
}
document.getElementById('to').onchange = function(e){
temp.to = e.target.value;
goAjax();
}
function goAjax(){
if(temp.from && temp.to && new Date(temp.from) < new Date(temp.to)){
//do ajax call
console.log('valid')
}
}
<input type="date" id='from'/>
<br>
<input type="date" id='to'/>
I would have captured the change event for both elements :
$("#search_date1, #search_date2").on('change',function(){
var d1 = $("#search_date1").val();
var d2 = $("#search_date2").val();
$.ajax({...});
});
What you do in your edit may work, but it would be better (and easier) do something like this
var myApp = {};
myApp.original_search_date1 = $("#search_date1").val();
myApp.original_search_date2 = $("#search_date2").val();
myApp.search_date1 = $("#search_date1").val();
myApp.search_date2 = $("#search_date2").val();
document.getElementById('search_date1').onchange = function (e) {
if ($("#search_date1").val() != myApp.search_date1) {
myApp.search_date1 = $("#search_date1").val();
sendAjax();
}
});
document.getElementById('search_date2').onchange = function (e) {
if ($("#search_date2").val() != myApp.search_date2) {
myApp.search_date2 = $("#search_date2").val();
sendAjax();
}
});
function sendAjax() {
if (myApp.original_search_date1 !== myApp.search_date1 &&
myApp.original_search_date2 !== myApp.search_date2) {
$.ajax({
...
});
}
}
Cant you just set a variable to check if its been changed with true/false then run the script if both variables are true.
Something like,
var searchOneToggled = false,
searchTwoToggled = false;
$('#search_date_one').on('input', function() {
searchOneToggled = true;
runYourFunction();
});
$('#search_date_two').on('input', function() {
searchTwoToggled = true;
runYourFunction();
});
function runYourFunction() {
if(searchOneToggled === true && searchTwoToggled === true) {
alert('hello world');
}
}
I have this working JS which checks if different checkboxes are or not checked and asigns a different price for each one that will later be summed up.
function priceCandy1() {
var priceCandy1 = 0;
var candy = document.getElementById("candy1");
if(candy.checked==true)
{
priceCandy1=13;
}
return priceCandy1;
}
function calculateTotal()
{
var totalPrice = priceCandy1() + priceCandy2() + priceCandy3();
document.getElementById('totalid').innerHTML = "$" + totalPrice;
}
Now I'm trying to code the equivalent in jQuery and this function does work:
$(function () {
var priceCandy1 = 0;
var candy = $('#candy1');
$('#candy1').on('click',function () {
if (candy.is(':checked')) {
priceCandy1 = 13;
}
});
return priceCandy1;
});
But I can't grab the returned price into a function that will add up every priceCandy#. Out of scope but I don´t know how to fix it.
If it is an issue of scope like you say, you could declare priceCandy1 outside the function, as a global variable.
var priceCandy1;
$(function () {
priceCandy1 = 0;
var candy = $('#candy1');
$('#candy1').on('click',function () {
if (candy.is(':checked')) {
priceCandy1 = 13;
}
});
});
Then use priceCandy1 in your totalPrice function and it should be able to fetch it.
Wrap them in the same function:
$(function () {
var priceCandy1 = function() {
if($('#candy1').is(':checked')) {
return 13;
}
return 0;
},
calculateTotal = function()
{
var totalPrice = priceCandy1() + priceCandy2() + priceCandy3();
$('#totalid').text('$' + totalPrice);
};
calculateTotal();
});
So this is a part of greasemonkey userscript. It's an adviser for an online game. At the end of it i've got this:
function do_login() {
// var loc = reg2.exec(document.location.href);
//Auto backing to login page
if (document.location.href.search("logout") != -1) {
window.setTimeout(function () {
document.location.href = "http://www" + gamepage;
}, 100);
}
else {
//login
try {
var logindata = explode(GM_getValue("logindata", "[]"));
}
catch (err) {
var logindata = new Array;
}
unsafeWindow.showDiv("login_div");
$("login_div").style.zIndex = "20";
$("login_div").getElementsByClassName("kh_btn")[0].addEventListener("click", function () {
var currServer = $("l_server").value;
var currUser = $("l_loginname").value.toLowerCase();
GM_setValue(lng + "_" + currServer + "_username", currUser);
}, false);
function submit_login(currUserNr) {
$("l_server").value = logindata[currUserNr][1];
$("l_loginname").value = logindata[currUserNr][2];
$("l_password").value = logindata[currUserNr][3];
$("login_div").getElementsByClassName("kh_btn")[0].click();
}
var newdiv = createElement("div", {style: "position:absolute;top:0px;left:0px;width:412px;padding:10px;background-color:#999;-moz-border-radius:10px;"}, $("login_div"));
for (var v = 0; v < logindata.length; v++) if (logindata[v][1] != "0") {
var newbutton = createElement("button", {type: "button", class: "cursorclickable", id: "autologin" + v, style: "width:200px;height:20px;margin:3px;"}, newdiv, texte["server"] + " " + logindata[v][1] + "." + logindata[v][0] + ": " + logindata[v][2]);
newbutton.addEventListener("click", function () {
submit_login(this.id.replace("autologin", ""));
}, false);
}
newdiv = null;
newbutton = null;
}
}
It's executed when script finds "logout" in the url.
Now, everything works, it's entering main-page, creating a button, the button itself works, but now i would like to execute "onlick" automatically.
You could select the element and then invoke the .click() method:
document.querySelector('#myElement')[0].click();
I'm having trouble with designing a class which exposes its actions through callbacks. Yes my approach works for me but also seems too complex.
To illustrate the problem I've drawn the following picture. I hope it is useful for you to understand the class/model.
In my approach, I use some arrays holding user defined callback functions.
....
rocket.prototype.on = function(eventName, userFunction) {
this.callbacks[eventName].push(userFunction);
}
rocket.prototype.beforeLunch = function(){
userFunctions = this.callbacks['beforeLunch']
for(var i in userFunctions)
userFunctions[i](); // calling the user function
}
rocket.prototype.lunch = function() {
this.beforeLunch();
...
}
....
var myRocket = new Rocket();
myRocket.on('beforeLunch', function() {
// do some work
console.log('the newspaper guys are taking pictures of the rocket');
});
myRocket.on('beforeLunch', function() {
// do some work
console.log('some engineers are making last checks ');
});
I'm wondering what the most used approach is. I guess I could use promises or other libraries to make this implementation more understandable. In this slide using callbacks is considered evil. http://www.slideshare.net/TrevorBurnham/sane-async-patterns
So, should I use a library such as promise or continue and enhance my approach?
var Rocket = function () {
this.timer = null;
this.velocity = 200;
this.heightMoon = 5000;
this.goingToMoon = true;
this.rocketStatus = {
velocity: null,
height: 0,
status: null
};
this.listener = {
};
}
Rocket.prototype.report = function () {
for (var i in this.rocketStatus) {
console.log(this.rocketStatus[i]);
};
};
Rocket.prototype.on = function (name,cb) {
if (this.listener[name]){
this.listener[name].push(cb);
}else{
this.listener[name] = new Array(cb);
}
};
Rocket.prototype.initListener = function (name) {
if (this.listener[name]) {
for (var i = 0; i < this.listener[name].length; i++) {
this.listener[name][i]();
}
return true;
}else{
return false;
};
}
Rocket.prototype.launch = function () {
this.initListener("beforeLaunch");
this.rocketStatus.status = "Launching";
this.move();
this.initListener("afterLaunch");
}
Rocket.prototype.move = function () {
var that = this;
that.initListener("beforeMove");
if (that.goingToMoon) {
that.rocketStatus.height += that.velocity;
}else{
that.rocketStatus.height -= that.velocity;
};
that.rocketStatus.velocity = that.velocity;
if (that.velocity != 0) {
that.rocketStatus.status = "moving";
}else{
that.rocketStatus.status = "not moving";
};
if (that.velocity >= 600){
that.crash();
return;
}
if (that.rocketStatus.height == 2000 && that.goingToMoon)
that.leaveModules();
if (that.rocketStatus.height == that.heightMoon)
that.landToMoon();
if (that.rocketStatus.height == 0 && !that.goingToMoon){
that.landToEarth();
return;
}
that.report();
that.initListener("afterMove");
that.timer = setTimeout(function () {
that.move();
},1000)
}
Rocket.prototype.stop = function () {
clearTimeout(this.timer);
this.initListener("beforeStop");
this.velocity = 0;
this.rocketStatus.status = "Stopped";
console.log(this.rocketStatus.status)
this.initListener("afterStop");
return true;
}
Rocket.prototype.crash = function () {
this.initListener("beforeCrash");
this.rocketStatus.status = "Crashed!";
this.report();
this.stop();
this.initListener("afterCrash");
}
Rocket.prototype.leaveModules = function () {
this.initListener("beforeModules");
this.rocketStatus.status = "Leaving Modules";
this.initListener("afterModules");
}
Rocket.prototype.landToMoon = function () {
this.initListener("beforeLandToMoon");
this.rocketStatus.status = "Landing to Moon";
this.goingToMoon = false;
this.initListener("afterLandToMoon");
}
Rocket.prototype.landToEarth = function () {
this.initListener("beforeLandToEarth");
this.stop();
this.rocketStatus.status = "Landing to Earth";
this.initListener("afterLandToEarth");
}
Rocket.prototype.relaunch = function () {
this.initListener("beforeRelaunch");
this.timer = null;
this.velocity = 200;
this.heightMoon = 5000;
this.goingToMoon = true;
this.rocketStatus = {
velocity: 200,
height: 0,
status: "relaunch"
};
this.launch();
this.initListener("afterRelaunch");
}
init;
var rocket = new Rocket();
rocket.on("afterLaunch", function () {console.log("launch1")})
rocket.on("afterLandToMoon", function () {console.log("land1")})
rocket.on("beforeLandToEarth", function () {console.log("land2")})
rocket.on("afterMove", function () {console.log("move1")})
rocket.on("beforeLaunch", function () {console.log("launch2")})
rocket.launch();
You can add any function before or after any event.
This is my solution for this kinda problem. I am not using any special methods anything. I was just wonder is there any good practise for this like problems. I dig some promise,deferred but i just can't able to to this. Any ideas ?
The script below works. However, I would like to use it along with a conditional IF statement to say "If the state is Online, then changeIt.style.visibility = 'visible'; else/if not then changeIt.style.visibility = 'hidden';
I really tried, but didn't manage to use IF with imgTmp.
function checkimage() {
var imgTmp = new Image();
imgTmp.onload = function() {
printState("Online");
};
imgTmp.onerror = function() {
printState("Offline");
};
imgTmp.src = "http://xxx/test.png?_=" + (+new Date());
}
function printState(state) {
document.getElementById("div1").innerHTML = " + state + ";
}
printState();
setInterval(checkimage, 200);
Just edit your printState or, create other function to change the something you want visibility...
function printState(state) {
document.getElementById("div1").innerHTML = " + state + ";
if (state === 'Online') {
changeIt.style.visibility = 'visible';
} else {
changeIt.style.visibility = 'hidden';
}
}