I'm having one little iritating problem. I have simple if condition in javascript code.
It goes something like this:
if (istinito)
{
alert ('123');
document.getElementById('obavestavanje').value="Pobedi "+ime_igraca+"!!!";
kraj=true;
}
Alert apears when istinito=true, but element with id="obavestenje" never get its value, and variable kraj never is set to true. Variable kraj is global variable, and there are no conflicts with other parts of the JS code.
Any ideas why code stops after alert?
Looks like document.getElementById('obavestavanje') is returning null. You are trying to de-reference the null reference by using document.getElementById('obavestavanje').value which results in null pointer exception. If you look into the console, you should see some exception being raised. It is always a good idea to check if the document.getElementById() is returning a valid object before trying to dereference it.
e.g.
if (istinito)
{
alert ('123');
element = document.getElementById('obavestavanje')
if(element){
element.value="Pobedi "+ime_igraca+"!!!";
}
kraj=true;
}
First advice i could give you:
Use more console logging for debugging. Almost any modern browser got a console to debug and other things.
if (istinito) {
console.log("i am here");
}
from that same console you can also execute commands. Those dom manipulations are easily done from the console. just run them and see if it works.
the code:
document.getElementById('obavestavanje').value = "some value"
looks ok. nothing wrong with it. i guess you don't have an element with id "obavestavanje" ?
Looks like your code is okay. And you are sure you have an element by id 'obavestavanje'. Could you please tell what element is it? Is it a button, textbox or someting like that?
Also the String in the "Pobedi "+ime_igraca+"!!!" , what is 'ime_igraca'? Is it a variable and if it is have you defined this variable somewhere?
Or did you mean to give the value "Pobedi ime_igraca !!!" ??
Thanks
Ranis MK
Related
I am still new a Javascript tried earching and tried the development tool in Chrome, too see if I could find the problem.
Working in Intellij IDEA 13, Java, javascript and xhtml.
My problem is that I have a piece of javascript, then in IDEA when moused over, says that
Expression Expected
the javascript code looks the following
<script type="text/javascript>
function nameOfFunction(){
if(#{trendAnalysisLocationReportController.model.showTargetLine}){
this.cfg.series[this.cfg.data.length-1].pointLabels = {
show: false
};
}
}
<\script>
the method in the if sentence is a java method with a boolean return value.
the error is shown when hovering
'#{'
if Had a look at the following questions, before :
Expected Expression
boolean in an if statement
But didnt get me a solution.
what Iam I doing wrong ?
It looks as though the problem is the part that you've got within the #{...} block. Without knowing the context, it's hard to be sure, but is this something in a view/JSP page that's supposed to be replaced with a property at runtime? The if block will expect the part inside the brackets to be a boolean value, so if that's rendered to either 'true' or 'false' it would execute at runtime but would likely show the error you're seeing in your IDE as it's not actually a valid piece of JavaScript. If, on the other hand, you're expecting to be able to call your Java method/property from your JavaScript code, you're going to need to do something that requests that value from the server-side code - AJAX or similar.
Also worth noting that we can't see what this.cfg is supposed to represent. If that's your entire script block, then there's nothing that defines the cfg object within the current scope.
One last thing, you should change the <\script> end element to as it won't be understood properly by some browsers.
k this is probably something very easy but for some reason i am getting an error when trying to use javascript to change style.height.
My javascript looks like this:
document.getElementById('div').style.height=100px;
I have also tried
document.getElementById('div').style.height='100px';
document.getElementById('div').style.height='100';
document.getElementById('div').style.height=100;
and get the same error every time.
The error i am getting is:
document.getElementById('div') is null
I get this error in my firebug console. Thanks.
You probably don't have an element with id="div".
Or you're running your code before the body exists.
this have to work fine :
document.getElementById('div').style.height='100px';
please check your html code, and try in the console :
document.getElementById('div').style.height;
and see what returns after and before
(maybe its working and you cant see it, you can check it adding an background-color)
The book I am reading tells me to open up the JavaScript console and try the code "foo: bar".indexOf(":"). I've tried it in many ways. I tried removing quotation marks, putting it inside a show() and alert() function. I just can't seem to tease anything out.
Has something changed in JavaScript? Has the author made a mistake? Am I supposed to get no return? Do I need to append document.write, perhaps? Any help greatly appreciated.
Yes something changed in Firefox 5+
However the console (ctrl-shift-k) still works
In the error console (ctrl-shift-J) you will need to wrap it in alert:
foo:bar is a property definition in json, and indexOf is supposed to deal with a left value (string variable, constant, or at least something that can have characters in it. I don't know why the book you are reading wants you to do this, but it doesn't seem to be correct. The correct way to use indexOf would be :
var myObject = {
foo:"bar"
}
alert(myObject.foo.indexOf("a"));
try like follows, it should work. Generally the indexOf() will return -1 if the value to search for never occurs.
var str="foo:bar";
document.write(str.indexOf(":") + "<br />");
The output should be 3
I have a function that is parsing xml which contains javascript function calls. An example of this is:
eval(getElementText(PropValue[0]));
getElementText(PropValue[0] = top.hidePopWin()
I have followed this call up to the hidePopWin function and watched it complete from the top of the function to the bottom of the function.
Everything looks in order however I get this pesky error in Firefox: top is null
As you have probably guessed hidePopWin closes the popup window that is currently displayed.
So, hidePopWin is called and it goes through just fine (in fact the popup does in fact close), but after that is the problem. It doesn't go to the next step. I get the top is null message in Firefox (firebug) and it just stops.
The only other thing I need to mention is that this whole process starts on a double click event (legacy code). There is also a single click event that fires as well. At first I thought maybe that was the issue, however, I took out the reference to the onclick event and I still get the same message.
So I'm thinking that it has something to do with the eval statement. Just for more information I am placing a console.log("1") above the eval statement and a console.log("2") below the eval. The "1" prints, the "2" does not.
Does anyone have any ideas as to what might be the issue?
Update:
if(getElementText(PropValue[0]) == "top.hidePopWin();"){
console.log('here');
top.hidePopWin();
console.log('end');
}else{
console.log(getElementText(PropValue[0]));
eval(getElementText(PropValue[0]));
}
OK I tried the above... I see the "here" statement, but it still says top is null. The "end" statement never prints. When I click on the top is null in FF it highlights the eval statement??? So I don't know what the heck is going on.
no, but could you change the code to directly execute the code outside eval and test?
So, change, eval(getElementText(PropValue[0]));
to
top.hidePopWin();
see if you get the same error.
is 'top' visible in that scope if you breakpoint in FF (on the console.log('here') line? It's sounding like there is no such variable (I don't know why the popup closes though).
OK... This may not be the best way to go, but I did finally get it to work. Per the suggestion to change the code to run top.hidePopWin(). I tried those suggestions however I was still getting the top is null issue.
In desperation I took out the "top." and now it works. So I'm guessing there was not a "top" variable (wierd notation in my opinion).
So now I'm capturing if the string is equaling "top.hidePopWin()" and then instead of calling the eval I'm just calling the function hidePopWin();
Seems to work. Let me know if there is another way of going about this.
Does anybody knows why this snippet returns false even if the passed string is "Active"?
if ($('status_'+id).getText()=="Active")
I've also tried changing the code to
if ($('status_'+id).getText()==String("Active"))
and
if (String($('status_'+id).getText())=="Active")
and still no luck.
I've also checked $('status_'+id).getText() through console.log to verify if it really returns "Active"
i wonder why it doesnt work?
any ideas?
Silly question: are you sure the returned string doesn't contain spaces?
The first step in any debugging task is to check your assumptions. Use a debugger or a series of alerts to check the following:
what's the value of id?
does$('status_'+id) evaluate to a DOM
element?
what does
$('status_'+id).getText() actually
return