jquery animation of specific attributes

问题:

So I'm using gRaphael to create some charts. This is creating a cool bar chart line with some dots in it. Those dots have the ... nodes with x=10 y=20 as their attributes. Example

rect x="135.8" y="115.8" width="8.399999999999999" height="8.399999999999999" r="0" rx="0" ry="0" fill="#ff0000" stroke="none"

I want to use jquery to animate this guy if possible. The thing is if I do

$("rect").click(function({
 $(this).animate({
   'x':30
 });
});

In order to animate the x coordenate it doesn't work for obvious reasons I guess?? hehe. Also I've tried setting the attribute x to a variable and trying to animate that and nothing. Can any one help me with animation and svg with gRaphael?

This for instance works

$("rect").live('click',function(){  $(this).attr('x',100);});

it moves the node but ofcourse doesn't animate it

Thanks!

回答1:

You can definitely animate a property by doing so

$("rect")
    .animate(
        { x: 100 },
        {
            duration: 1000,
            step: function(now) { $(this).attr("x", now); }
        });

You do not need to save that property in CSS.

回答2:

I'm working on project which uses svgs. While I got the above to work, the animated value went from 0 to where-ever even if it has a value before the animation. So I used this instead (initial value for cy is 150):

$('#navlet .li1').mouseenter(function(){
    $({cy:$('#nav_dot').attr('cy')})
    .animate(
    {cy: 60},
    {duration:200,step:function(now){$('#nav_dot').attr('cy', now);}});
});

回答3:

In fact, there is a way to animate a specific attribute:

$("rect").each(function(){
   $(this).css("MyX",$(this).attr("x"))
   .animate({MyX:500},{step:function(v1){$(this).attr("x",v1)}})
})

回答4:

I found a way to use the jQuery call without running into the problem that the attribute gets reset to 0 when the animation starts like some other answers here

Lets say we want to animate the width and height attribute of an img tag element with id image. To animate it from its current value to 300 we could do this:

var animationDiv= $("<div></div>"); //we don't add this div to the DOM
var image= $("img#image");
//could use any property besides "top" and "left", but the value must be valid, that means concatenating a "px" to numerical attributes if they don't have it already (and removing them in the step callback if they do)
animationDiv.css("left", image.attr("width")); 
animationDiv.css("top", image.attr("height")); 
animationDiv.animate(
    {
        left: 300,
        top: 300
    },
    {
        duration: 2500,
        step: function(value, properties) {
            if (properties.prop == "left")
                 image.attr("width", value + "px")
            else
                 image.attr("height", value + "px")
        }
    }
)

In this approach we use a div that is not inside the DOM and animate values in it, we then use the div CSS values to animate our element. Not very pretty but gets the job done, if you need to stop the animation you can call .stop() on animationDiv.

jsfiddle

回答5:

You can only animate valid CSS properties that have a numeric value. Colors can be animated via some plugins. Since 'x' is not a valid CSS property, you won't be able to animate it using jQuery's built in .anmiate() function.

I think you'd have to pretty much write your own animation function to increment the value of x each passthrough of a timeout.