jQuery Tutorial - 59 - removeAttr Video Lecture | Importance of jQuery in Website Development - IT & Software

and essentially what this means is that
when we have it checked the value of
this is on then we check it again the
value is nothing so we don't have a
value we the value attribute is is
defined but we don't actually have a
value so what we can do now is we can go
ahead and check that this state is on or
off now halfway through the tutorial
I've completely changed my mind and I
thought to myself and I've sort of
thoughts myself well when we check this
we just want to enable this and when we
uncheck it we want to disable it again
so we'll go with that it's probably a
bit more practical for those of you that
want to go ahead and use this so I'm
going to create an if statement and the
condition is if if state is on so if the
state is on that means that we agree and
we can go ahead and enable the button
otherwise if the state is equal to
nothing we want to go ahead and disable
the button once again so we'll focus on
disabling the button again well sorry
we'll focus on enabling enabling the
button first and with this we're using
remove attribute which is what the whole
tutorial the point of the tutorial is
about so we want to reference this
obviously again our currently selected
object and we want to use remove
attribute and we're gonna do we're gonna
know it's of you know tell this function
if you like which attribute we want to
remove and the attribute we want to
remove completely as the disabled
attribute so this will literally just
get rid of this like that so that's all
we're doing with this button here and OH
in actual fact sorry now it's not this
it's hash continue because we're
referencing the button itself sorry
we're not referencing the checkbox so
we're removing the attribute disabled
let's just go ahead and check that out
so when I click on it
we go into it obviously change will grab
the state if the state is equal to on ie
if it's checked like we saw earlier when
we alerted out we're going to go ahead
and remove the attribute from this
continue button here so when we click it
you can see that that's enabled and
obviously when we uncheck it we still
have a state change but now we're stuck
with the enabled button if for example I
click on agree and then I don't agree
my own check I won't want to continue or
I won't want my users to continue if I
was to you know have this on on my
website so if the state is equal to 0
equal to nothing when we or we could say
null here which would be better if the
state is equal to null when we have
changed the checkbox I has it been
unchecked we want to go ahead and reduce
able the continue button so we want to
add the attribute disabled and the value
of this is disabled much like we did
before this here let's just bring it
down is the equivalent to disabled
equals disabled like that so that's how
that looks inside of jQuery however when
we apply it to the element it will you
know create the attribute so once again
when we click it we enable the button
but now when we uncheck it an actual
fact I think that's probably that's
probably because it doesn't equal null
is just a blank value yeah okay so now
when we click on it click it the value
or the state of this from the value is
equal to on otherwise if the state is
equal to nothing which is when we
uncheck it then we go ahead and add this
attribute disabled to the button again
so we're sort of like toggling between
states if you like so you could go ahead
and you could sort of apply this to a
form and then at the end of the form you
could have this agree button and then
continue you know you might have this
here wrapped around the form like this
and then you might have some agreement
here and then they would read the
agreement and either agree and then
continue to submit the form or or they
could uncheck and then they wouldn't be
able to click just bear in mind that
this is a button type so to have it
actually submit the form you would have
it as a submit type and obviously
because we're referencing by the ID this
doesn't make a difference and it still
works so we can click continue and we
can submit the form
you see we've just got a little question
mark here but obviously if you had an
action it would submit so that's how
we've toggled between this using remove
that tribute was the focus of this
tutorial however you know it's boring
just to talk about one attribute without
it's practical application so I've
popped it into this small little piece
of functionality that goes ahead goes
ahead and toggles this based on a
checkbox value