首次使用后，slideUp和slideDown动画不起作用

Question

I have used jQuery to build something like a dropdown, but it only works for the first two clicks, and then it doesn't. How can I make a dropdown? Can it be done with a loop? (I have not learnt loop yet, so any solution would work.)

For Each SLIDEUP and SLIDEDOWN I wanted to make different TIME....

 jQuery(document).ready(function() { jQuery(".click-on").click(function() { jQuery(".box").slideUp(2000, function() { jQuery(".click-on").click(function() { jQuery(".box").slideDown(500); }); return false; }); return false; }); }); 

 .box { width: 300px; height: 300px; background-color: skyblue; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <p id="fan">THIS IS A FAN</p> <p id="gun">THIS IS A GUN</p> <p class="click-on">Click Here</p> <div class="box"></div> 

Answer 1

Do you want to achieve something like that?

$(document).ready(function(){
  $(".click-on").click(function(){
    $('.box').slideToggle();
  });
});

https://jsfiddle.net/jsrc9mbd/1/

Answer 2

The answer by @hetious is what I would have given - but having just seen the comment that slide-up and slide-down should have different times, you'll have to do this instead. Basically, check when you click whether the box is visible or not, and either slideUp or dlideDown accordingly:

jQuery(document).ready(function() {
  jQuery(".click-on").click(function() {
    var box = jQuery(".box");
    if (box.is(":visible")) {
      box.slideUp(2000);
    }
    else {
      box.slideDown(500);
    }
  });
);

(Note that I have extracted a variable for jQuery(".box") , just to save some typing. And you can also use $ as an alias for jQuery to save yet more (the only reason this wouldn't work is if you are using another library which defines a global $ variable, which a few do.)

Answer 3

This is because you misunderstand the meaning of the .click() function.

.click() sets the handler function each time when the click event is triggered from the selected DOM.

Since you have called another .click() within the callback of .slideUp() , you are actually replacing the handler function. In your current logic, the obvious fix is to do infinite callback after each click like:

jQuery(".click-on").click(function(){
    jQuery(".box").slideUp(2000, function(){
        jQuery(".click-on").click(function(){
            jQuery(".box").slideDown(500,function(){
                jQuery(".click-on").click(function(){ 
                    jQuery(".box").slideUp(2000, function(){//Repeating callbacks... ...
            });
        });
    });
});

and seriously it is very bad. Such implementation should not be done.

Instead, it is better for you to have a conditional checking for each click, so the logic will determine itself either .slideUp() or .slideDown() should be called. It should be like

$(".click-on").click(function(){//you can also use $ instead of jQuery
    //do some conditional check here
    if(isSlidedUp)$(".box").slideDown(1000);
    else $(".box").slideUp(1000)
});

or even better you use .slideToogle() .

$(".click-on").click(function(){
    $(".box").slideToggle(1000)
}