'showPDF' is declared but its value is never read - javascript

some background information: i have a button in my html file that should activate the showPDF function but it tells me that its value is never read
javascript:
HM.PDFViewer =
{
init: function()
{
//---
},
showPDF: function()
{
function showPDF(x) {
x.style.display = "none";
var embed = document.createElement("EMBED");
embed.setAttribute("src", "/pdf/Doku.pdf");
embed.classList.add("size");
document.body.appendChild(embed);
}
},
};
the button in my html looks like this:
<button type="button" id="show" onclick="showPDF(this)" >PDF anzeigen</button>
help would be greatly appreciated as i can't seem to find any answers in different questions

You just need to remove the duplication of the showPDF function. you don't need the inner one.
showPDF: function()
{
x.style.display = "none";
var embed = document.createElement("EMBED");
embed.setAttribute("src", "/pdf/Doku.pdf");
embed.classList.add("size");
document.body.appendChild(embed);
},

Related

Is there a way to add a function to my current button?

I am using JS and HTML. I have a button that displays the next section of html, but I wanted to add an additional function.
// Display Thanks Message
document.addEventListener('DOMContentLoaded', ()=>{
document.getElementById("btn").addEventListener("click", addPerson function() {
q5.style.display = "none";
end.style.display = "block";}
});
In this addPerson is the function I am trying to include. In this current code I keep getting syntax errors.
Call addPerson() inside the function.
// Display Thanks Message
document.addEventListener('DOMContentLoaded', () => {
document.getElementById("btn").addEventListener("click", function() {
addPerson();
q5.style.display = "none";
end.style.display = "block";
}
});
});

How to close a picture after displaying it?

I wrote JavaScript code that displays an image on click for my site. How do I add a way for it to close after users are done?
function picture() {
var a = document.getElementById('QR');
a.innerHTML = "https://www.yoapoyord.com/wp-content/uploads/2017/09/Elfactor3.jpg";
a.style.display = 'block';
}
<img id="QR" src="https://www.yoapoyord.com/wp-content/uploads/2017/09/Elfactor3.jpg" style="display:none;" />
<button onclick="picture()">Apoyar</button>
https://jsfiddle.net/dmtakr3w/
To close that image after displaying it, you can remove the node by taking the parent element and invoking .removeChild(node); on the parent element.
function closePicture() {
var a = document.getElementById('QR');
var parent = a.parentNode;
console.log(parent);
parent.removeChild(a);
}
If you assign this function to a button you are able to close the image by clicking it:
<button onclick="closePicture()">Close</button>
You can also do a setTimeout() to automatically close the image after a certain amount of seconds or so:
// Removes the image after 5 seconds upon opening:
function picture() {
var a = document.getElementById('QR');
a.innerHTML = "https://www.yoapoyord.com/wp-content/uploads/2017/09/Elfactor3.jpg";
a.style.display='block';
setTimeout(function() {
var a = document.getElementById('QR');
a.parentNode.removeChild(a);
}, 5000);
}
As Sag1v said in the comments, just add an on click event to the QR code tag and switch the display back to none.
function picture() {
var a = document.getElementById('QR');
a.innerHTML = "https://www.yoapoyord.com/wp-content/uploads/2017/09/Elfactor3.jpg";
a.style.display = 'block';
}
function closePicture() {
var a = document.getElementById('QR');
a.style.display = 'none';
}
<img id="QR" src="https://www.yoapoyord.com/wp-content/uploads/2017/09/Elfactor3.jpg" style="display:none;" onclick="closePicture()" />
<button onclick="picture()">Apoyar</button>

How can I make an input change its src with an onclick?

I'm trying this and my background changes color (what I want) but the src of the input only changes on the second time I click it. how can I make it change the source on the first click? Also how can I change the src back to the original with a second click?
<input id="showHideContainer" type="image" src="on.png " height="3%" width="2%" alt="On" onclick="toggle();">
<script>
document.getElementById('showHideContainer').onclick = function () {
divTest = document.getElementById('header');
if (divTest.style.display === "none") {
divTest.style.display = 'block';
} else {
divTest.style.display = "none";
};
$('body').toggleClass('style2');
$('#showHideContainer').click(function(){
$('#showHideContainer').attr('src', 'off.png');
});
}
</script>
You need to determine the current state of the obj then toggle it with the other
$('#showHideContainer').click(function(){
var off = $(this).attr('src').indexOf('off.png')>-1;
$(this).attr('src', (off?'on.png':'off.png'));
});
Quick fix. You are now attaching anoter eventhandler on the first click on the #showHideContainer, that is why it's not firing the first time. This trimmed version of your code should get you the expected result, also see the other answer to look at the state of your element attribute:
document.getElementById('showHideContainer').onclick = function () {
divTest = document.getElementById('header');
if (divTest.style.display === "none") {
divTest.style.display = 'block';
} else {
divTest.style.display = "none";
};
$('body').toggleClass('style2');
var off = $(this).attr('src').indexOf('off.png')>-1;
$(this).attr('src', (off?'on.png':'off.png'));
}

Where to Specify Java Script in a asp:content page?

I had a html page where I was using java script to collapse and expand Gridview. However, I had to switch to a asp:content page(part of a master page) where I don't have head tag.
I tried specifying the java script inside the asp:content but it is not working.
Also, I tried specifying itmy master page still its not working.
How to deal with it any ideas?
Here is the script.
<script type="text/javascript">
function collapseExpand(obj) {
var gvObject = document.getElementById(obj);
var imageID = document.getElementById('image' + obj);
if (gvObject.style.display == "none") {
gvObject.style.display = "inline";
imageID.src = "~/ims/Images/bullet_toggle_minus.jpg";
}
else {
gvObject.style.display = "none";
imageID.src = "~/ims/Images/bullet_toggle_plus.jpg";
}
}
</script>
You can specify script at any place in your page. As soon as browser sees script tag it executes script inside it.
But in this case I think you should execute your code inside window.onload event handler because you need to wait until you markup is loaded and then you need to call your function. For example:
<script type="text/javascript">
window.onload = function(){
function collapseExpand(obj) {
var gvObject = document.getElementById(obj);
var imageID = document.getElementById('image' + obj);
if (gvObject.style.display == "none") {
gvObject.style.display = "inline";
imageID.src = "~/ims/Images/bullet_toggle_minus.jpg";
}
else {
gvObject.style.display = "none";
imageID.src = "~/ims/Images/bullet_toggle_plus.jpg";
}
}
collapseExpand("yourOfYourElement");
}
</script>
Or you can register calling your function after some event raises. For example:
document.onclick = function(){
collapseExpand("yourOfYourElement");
}

Page resets after javascript function finishes

I'm doing a simple html page for a project.
I have a submission form.I use jquery to validate it (no sure if i'm doing ir right).
After the submission is validated,i want to save the user's details(name,password),in an array. The array is created when the script loads.
I added the function SubmitUser() to the onclick event,but when the function finishes,and adds the user,the page resets,and the variables are reset.
I wonder if someone could point out to me what i'm doing wrong.
Thanks in advance,
Boris
Here's the script code:
var userArray = new Array();
var passArray = new Array();
var userNumber = 0;
//Adding rules for validation
$(document).ready(function(){
$("#registerForm").validate({
rules: {
password: {
required: true,
minlength: 8
}
}
});
});
//Add a method to validate
$(document).ready(function(){
$.validator.addMethod("username", function(value, element) {
return this.optional(element) || /^[a-zA-Z]+$/i.test(value);
}, "Field must contain only letters");
});
//The function in question
function SubmitUser()
{
if($("#registerForm").valid())
{
var user = document.getElementById('username');
userArray[userNumber] = user;
userNumber++;
alert('Registered');
}
//Function to switch between the different pages in the menu.
function toggle(id) {
if(id=='LoginPage')
{
document.getElementById(id).style.display = 'block';
document.getElementById('WelcomePage').style.display = 'none';
document.getElementById('RegisterPage').style.display = 'none';
document.getElementById('GamePage').style.display = 'none';
}
if(id=='WelcomePage')
{
document.getElementById(id).style.display = 'block';
document.getElementById('LoginPage').style.display = 'none';
document.getElementById('RegisterPage').style.display = 'none';
document.getElementById('GamePage').style.display = 'none';
}
if(id=='RegisterPage')
{
document.getElementById(id).style.display = 'block';
document.getElementById('WelcomePage').style.display = 'none';
document.getElementById('LoginPage').style.display = 'none';
document.getElementById('GamePage').style.display = 'none';
}
if(id=='GamePage')
{
document.getElementById(id).style.display = 'block';
document.getElementById('WelcomePage').style.display = 'none';
document.getElementById('RegisterPage').style.display = 'none';
document.getElementById('LoginPage').style.display = 'none';
}
return false;
}
If you're looking to override the form's natural submit behavior, you can do this:
$(document).ready( function(){
$('#registerForm').submit( function(e){
e.preventDefault(); // suppress natural submit behavior
submitUser(); // your function
});
});
And since you're already using jQuery, you can greatly simplify your toggle code. For each block like this:
if(id=='WelcomePage')
{
document.getElementById(id).style.display = 'block';
document.getElementById('LoginPage').style.display = 'none';
document.getElementById('RegisterPage').style.display = 'none';
document.getElementById('GamePage').style.display = 'none';
}
...you can instead do this:
if( id === 'WelcomePage' ){
$('#'+id).show();
$('#LoginPage, #RegisterPage, #GamePage').hide();
}
Or even more generally, handle all your toggling cases with one line:
function toggle(id){
$('#LoginPage, #RegisterPage, #GamePage, #WelcomePage')
.hide()
.filter('#'+id).show();
}
You can try adding this to your onclick event (on your 'submit' button):
onclick="javascript:return SubmitFunction();"
OR in your form tag (For normal submit button):
onSubmit="javascript:return SubmitFunction();"
Make sure you are returning true or false in your function. if false is returned page won't reset/refresh.
When the page refreshes or changes, the JavaScript variables are reset... Thats the unfortunate truth. Make sure the function that the form is on returns false to stop it from changing the page - so SubmitUser() should look like:
function SubmitUser()
{
if($("#registerForm").valid())
{
var user = document.getElementById('username');
userArray[userNumber] = user;
userNumber++;
alert('Registered');
}
return false;
}
Now, to change pages look at using jQuery.html (Link) to load content in without actually changing the page (or jQuery.load (Link) to load an actual file, like games.html):

Categories

Resources