CODEWITHSUNDEEP
javascripthtmldom
stonedevil
stonedevil

Reputation: 45

How come i cannot get the value of an element in javascript

Firstly , i want to admit that i am not any good in javascript. In fact , it frustrates me to no end and i cannot seem to wrap my head around it , still giving it a shot.So i have this "js" file:

var url, tab,myNewTab;
function init(){
    chrome.tabs.query({currentWindow: true, active: true},function(tabs){
       url = tabs[0].url;
       tab = tabs[0]
       tabId = tabs[0].id;
       processTab();
    });
}

function processTab(){
    chrome.tabs.update(tabId, {selected: true});
    if (url.substring(0,5) === "http:")
    {
        console.log(window.location);
        url = insert(url , 4 , "s");
    }
    myNewTab = window.open('https://alexanderproxy33.appspot.com','_newtab' );

    myNewTab.onload = cont() ;
}
function insert(str, index, value) {
    return str.substr(0, index) + value + str.substr(index);
};
function cont()
{
    console.log(myNewTab.document.getElementById("input").value)
}
init();

There are many things that could have been done much better i guess but my question is this: the console.log line gives me an error cause null.I made the cont() function so it would load its elements so i could get them (as suggested by many people who are obviously right) but still nothing. The next part is a part of the html of the aforementioned site which i thought would trigger this:

<body>
    <div class="box">
        <h6>Basic Proxy</h1>
            <center>
                <form action="" method="get" accept-charset="utf-8" target="_blank">
                    <input name="url" type="text" class="txt" id="input" placeholder="type url here.." onfocus="this.value='';" />
                    <input type="submit" class="btn" value="Go" />
                </form>
            </center>
            <p class="footer">Instructions: Just type the URL of any web page in the input box above (
                <em>e.g. google.com</em> ) and hit Enter.</p>
            <p class="footer"></p>
    </div>
</body>

Thanks in advance

Upvotes: 1

Views: 118

Answers (1)

rgajrawala
rgajrawala

Reputation: 2188

myNewTab.onload = cont() ; is incorrect as you are executing cont and then setting its return value (i.e. undefined) as myNewTab.onload. Therefore, that line should be myNewTab.onload = cont;.

Upvotes: 2

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