現在、私のウェブサイトにポートフォリオ用の画像を表示するスライドショーがあります。それはうまく機能しますが、別のボックス/divで、画像の下に代替テキストまたはタイトルを使用してキャプションを追加したいと思います。
これはまったく可能ですか？もしそうなら、これを達成するためのチュートリアルやリソースを知っている人はいますか?
現時点では、これが私の画像の表示方法です
<ul class="slides">
<li><img src="Pictures/1.jpg" width="400" height="200" title = ""alt="Marsa Alam underawter close up" /></li>
<li><img src="Pictures/2.jpg" width="400" height="200" alt="Marsa Alam underawtzxcxzczxczxczxczer close up" /></li>
<li><img src="Pictures/4.jpg" width="400" height="200" alt="Marsa Alam underawccccter close up" /></li>
<li><img src="Pictures/3.jpg" width="400" height="200" alt="Marsa Alam underawtcxzczxcxzczcxcxzcer close up" /></li>
</ul>
画像を切り替えるには、このスクリプトをhttp://tutorialzine.com/2010/09/html5-canvas-slideshow-jquery/から使用します
$(window).load(function(){
// We are listening to the window.load event, so we can be sure
// that the images in the slideshow are loaded properly.
// Testing wether the current browser supports the canvas element:
var supportCanvas = 'getContext' in document.createElement('canvas');
// The canvas manipulations of the images are CPU intensive,
// this is why we are using setTimeout to make them asynchronous
// and improve the responsiveness of the page.
var slides = $('#slideshow li'),
current = 0,
slideshow = {width:0,height:0};
setTimeout(function(){
window.console && window.console.time && console.time('Generated In');
if(supportCanvas){
$('#slideshow img').each(function(){
if(!slideshow.width){
// Taking the dimensions of the first image:
slideshow.width = this.width;
slideshow.height = this.height;
}
// Rendering the modified versions of the images:
createCanvasOverlay(this);
});
}
window.console && window.console.timeEnd && console.timeEnd('Generated In');
$('#slideshow .arrow').click(function(){
var li = slides.eq(current),
canvas = li.find('canvas'),
nextIndex = 0;
// Depending on whether this is the next or previous
// arrow, calculate the index of the next slide accordingly.
if($(this).hasClass('next')){
nextIndex = current >= slides.length-1 ? 0 : current+1;
}
else {
nextIndex = current <= 0 ? slides.length-1 : current-1;
}
var next = slides.eq(nextIndex);
if(supportCanvas){
// This browser supports canvas, fade it into view:
canvas.fadeIn(function(){
// Show the next slide below the current one:
next.show();
current = nextIndex;
// Fade the current slide out of view:
li.fadeOut(function(){
li.removeClass('slideActive');
canvas.hide();
next.addClass('slideActive');
});
});
}
else {
// This browser does not support canvas.
// Use the plain version of the slideshow.
current=nextIndex;
next.addClass('slideActive').show();
li.removeClass('slideActive').hide();
}
});
},100);
// This function takes an image and renders
// a version of it similar to the Overlay blending
// mode in Photoshop.
function createCanvasOverlay(image){
var canvas = document.createElement('canvas'),
canvasContext = canvas.getContext("2d");
// Make it the same size as the image
canvas.width = slideshow.width;
canvas.height = slideshow.height;
// Drawing the default version of the image on the canvas:
canvasContext.drawImage(image,0,0);
// Taking the image data and storing it in the imageData array:
var imageData = canvasContext.getImageData(0,0,canvas.width,canvas.height),
data = imageData.data;
// Loop through all the pixels in the imageData array, and modify
// the red, green, and blue color values.
for(var i = 0,z=data.length;i<z;i++){
// The values for red, green and blue are consecutive elements
// in the imageData array. We modify the three of them at once:
data[i] = ((data[i] < 128) ? (2*data[i]*data[i] / 255) : (255 - 2 * (255 - data[i]) * (255 - data[i]) / 255));
data[++i] = ((data[i] < 128) ? (2*data[i]*data[i] / 255) : (255 - 2 * (255 - data[i]) * (255 - data[i]) / 255));
data[++i] = ((data[i] < 128) ? (2*data[i]*data[i] / 255) : (255 - 2 * (255 - data[i]) * (255 - data[i]) / 255));
// After the RGB elements is the alpha value, but we leave it the same.
++i;
}
// Putting the modified imageData back to the canvas.
canvasContext.putImageData(imageData,0,0);
// Inserting the canvas in the DOM, before the image:
image.parentNode.insertBefore(canvas,image);
}
});
スライドショーのCSSはこちら
#slideshow ul{
height:310px;
position:absolute;
top:10px;
width:410px;
}
#slideshow li{
position:absolute;
display:none;
z-index:10;
margin-left:-30px;
margin-top:-15px;
}
#slideshow li:first-child{
display:block;
margin-left:-30px;
margin-top:-15px;
}
#slideshow .slideActive{
z-index:1000;
}
#slideshow canvas{
display:none;
position:absolute;
z-index:100;
}
#slideshow .arrow{
height:86px;
width:60px;
position:absolute;
background:url('img/arrows.png') no-repeat;
top:50%;
margin-top:-43px;
cursor:pointer;
z-index:5000;
}
#slideshow .previous{ background-position:left top;left:0;}
#slideshow .previous:hover{ background-position:left bottom;}
#slideshow .next{ background-position:right top;right:0;}
#slideshow .next:hover{ background-position:right bottom;}