我的 Jquery 代码有问题。我正在尝试做一个画廊。我希望当人们单击图像时，将该图像附加到 div 并将其显示在屏幕中央。我的问题是图像大于当前屏幕尺寸。我调整图像大小以匹配屏幕大小，但是当我将其淡入 div 时，它会滞后。我不明白为什么会这样，而且我确信这不仅仅是因为图像很大，如果我不调整它的大小并让它离开屏幕，它就会很好地淡入。 HTML:
<!DOCTYPE HTML>
<html lang="en-US">
<head>
<meta charset="UTF-8">
<title>Gallery</title>
<link rel="stylesheet" href="Gallery.css">
</head>
<body>
<div class="gallery">
<div class="images">
<ul class="resize">
<li><img src="img/img1.jpg" alt="image1"></li>
<li><img src="img/img2.jpg" alt="image2"></li>
<li><img src="img/img3.jpg" alt="image3"></li>
<li><img src="img/img4.jpg" alt="image4"></li>
<li><img src="img/img5.jpg" alt="image5"></li>
<li><img src="img/img6.jpg" alt="image6"></li>
<li><img src="img/img7.jpg" alt="image7"></li>
<li><img src="img/img8.jpg" alt="image8"></li>
</ul>
</div>
<div class="backgroundOpacity"></div>
<div class="imageBox">
<img class="displayImage" src="" alt="displayImage">
<img class="loadingGif" src="img/loading.gif" alt="loadgindGif">
<img class="closeImage" src="img/closeImage.png" alt="close">
<p class="imageNumber">1</p>
</div>
</div>
<script type="text/javascript" src="jquery-1.8.2.js"></script>
<script type="text/javascript" src="Gallery.js"></script>
<script type="text/javascript">
var content = $('.gallery'),
gallery = new Gallery(content);
</script>
</body>
</html>
CSS:
*{
margin: 0;
padding: 0;
}
/*-------------------------gallery-----------------------*/
.gallery{
width: 1300px;
margin: 100px auto 0;
};
/*------------------------------------------------*/
/*-------------------------images-----------------------*/
.images{
width: inherit;
height: inherit;
}
.images li{
list-style-type: none;
float: left;
margin: 0 20px 20px 0;
width: 300px;
height: 150px;
cursor: pointer;
}
.resize img{
width: inherit;
height: inherit;
}
/*------------------------------------------------*/
/*-------------------------imageBox-----------------------*/
.imageBox{
background-color: white;
clear: both;
width: 300px;
height: 150px;
display: none;
position: fixed;
overflow: visible;
}
.backgroundOpacity{
background-color: black;
width: 5000px;
height: 5000px;
position: fixed;
left: 0px;
top: 0px;
opacity: 0.7;
display: none;
}
.loadingGif{
display: block;
position: absolute;
}
.displayImage{
display: none;
}
.closeImage{
position: absolute;
top: -10px;
right: -10px;
cursor: pointer;
}
.imageNumber{
position: absolute;
bottom: 0px;
left: 0px;
font-family: sans-serif;
font-size: 18px;
font-weight: bold;
opacity: 0.6;
}
/*------------------------------------------------
*/
和Java:
function Gallery (galleryDiv, resizeDuration, fadeInDuration) {
this.config = {
resizeDuration: 1000,
fadeInDuration: 500
};
this.galleryDiv = galleryDiv;
this.imagesUl = this.galleryDiv.find('.images ul');
this.images = this.imagesUl.find('img');
this.backgroundOpacity = this.galleryDiv.find('.backgroundOpacity'); // the background div which when is clicked hides the imageBox
this.imageBox = this.galleryDiv.find('.imageBox'); // where the images will be displayed when they'r clicked
this.closeButton = this.imageBox.find('.closeImage'); // top-right x
this.loadingGif = this.imageBox.find('.loadingGif'); // the animated gif that gives the effect of 'loading'
this.imageNumber = this.imageBox.find('.imageNumber'); // bottom-left text
this.displayImage = this.imageBox.find('.displayImage'); // image to be displayed
this.imagesWidth = new Array(); // the images default widths
this.imagesHeight = new Array(); // the images default heights
this.imagesLength = this.images.length // number of images
this.imageBoxSize = new Array(); // [0] is width, [1] is height
this.loadingGifSize = new Array() // [0] is width, [1] is height
this.resizeDuration = resizeDuration || this.config.resizeDuration; // duration to resize imageBox
this.fadeInDuration = fadeInDuration || this.config.fadeInDuration; // duration for image to fadeIn
this.init();
};
Gallery.prototype.init = function () { // puts things into move
this.getImageSize();
this.bind();
};
Gallery.prototype.bind = function () { // bind events
var self = this;
this.images.on('click', function () {
var index = $(self.images).index( $(this) );
self.showImage(index);
});
$(window).on('resize', function () { // center the imagebox whenever the window is resized
self.centerImageBox(self.imageBoxSize[0], self.imageBoxSize[1]);
});
$(this.closeButton).on('click', function () { // hide the image
// self.hideImage();
self.displayImage.hide();
self.displayImage.fadeIn(500);
});
$(this.backgroundOpacity).on('click', function () {
self.hideImage();
});
return this;
};
Gallery.prototype.getImageSize = function () { // get the default images sizes
var self = this;
this.imagesUl.removeClass('resize');
$.each(this.images, function (index, value) {
self.imagesWidth[index] = value.width;
self.imagesHeight[index] = value.height;
});
this.imagesUl.addClass('resize');
this.imageBox.show();
this.loadingGifSize = [this.loadingGif.width(), this.loadingGif.height()];
this.imageBox.hide();
return this;
};
Gallery.prototype.showImage = function (index) { // shows the image when it is clicked
var self = this,
imageWidth = this.imagesWidth[index], imageHeight = this.imagesHeight[index],
imageSrc = $(this.images[index]).attr('src'),
windowWidth = $(window).width(), windowHeight = $(window).height(),
ratio = imageWidth / imageHeight, margin = 100, // margin - the distance from the image borders to the window borders (if image is to big)
imageBoxHeight, imageBoxWidth;
// resize the image to the current monitor size
while(imageWidth > (windowWidth - margin) || imageHeight > (windowHeight-margin)){
if(imageWidth > windowWidth){
imageWidth = windowWidth - margin;
imageHeight = imageWidth / ratio;
}
else{
imageHeight = windowHeight - margin;
imageWidth = imageHeight * ratio;
}
}
//show imageBox and resize it
this.imageBoxSize = [imageWidth, imageHeight]; // captures the current imageBox size
this.imageNumber.text('Image ' + (index+1) + ' of ' + this.imagesLength) // set bottom-left text
this.displayImage.attr('src', imageSrc).css({
'width': imageWidth,
'height': imageHeight
});
this.backgroundOpacity.show();
this.imageBox.show();
this.loadingGif.show();
this.imageBox.animate({
'width': imageWidth,
'height': imageHeight
},{
duration: self.resizeDuration,
step: function () {
// center the image box with every resize;
imageBoxWidth = self.imageBox.width();
imageBoxHeight = self.imageBox.height();
self.centerImageBox(imageBoxWidth, imageBoxHeight);
// center the loadingGif
self.loadingGif.css({
'right': (imageBoxWidth - self.loadingGifSize[0])/2,
'top': (imageBoxHeight - self.loadingGifSize[1])/2
});
},
complete: function () {
self.closeButton.show();
self.imageNumber.show();
self.loadingGif.hide();
self.displayImage.fadeIn(500);
}
});
return this;
};
Gallery.prototype.hideImage = function () { // hide the image
this.imageBox.hide();
this.backgroundOpacity.hide();
this.closeButton.hide();
this.imageNumber.hide();
this.displayImage.hide();
return this;
};
Gallery.prototype.centerImageBox = function (width, height) {
var windowWidth = $(window).width(),
windowHeight = $(window).height();
this.imageBox.css({
'right': (windowWidth - width)/2,
'top': (windowHeight - height)/2
});
return this;
};
尝试使用大于 2000x2000 的大图像
最佳答案
这是由于图像太大造成的。事实上，使用 jQuery 的动画性能相当慢。我建议您在服务器上使用 imagemagick 创建小图像，其大小与您希望图库的宽度相同。之后动画将顺利运行。
关于javascript - jquery 调整图像大小，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/13383288/