尝试在我的项目中实施this example。我没有深入的jquery知识，之前没有使用javascript对象。
我需要的是，对此插件进行简单修改，以便在幻灯片更改时调用某些功能（回调功能）。
我无法弄清楚修改的位置。
有什么建议吗？
提前致谢。
这是JS（请更好地查看jsfiddle，它太长了，因为stackoverflow要求粘贴在这里）
(function( $, undefined ) {
$.Gallery = function( options, element ) {
this.$el = $( element );
this._init( options );
};
$.Gallery.defaults = {
current : 0, // index of current item
autoplay : false,// slideshow on / off
interval : 2000 // time between transitions
};
$.Gallery.prototype = {
_init : function( options ) {
this.options = $.extend( true, {}, $.Gallery.defaults, options );
// support for 3d / 2d transforms and transitions
this.support3d = Modernizr.csstransforms3d;
this.support2d = Modernizr.csstransforms;
this.supportTrans = Modernizr.csstransitions;
this.$wrapper = this.$el.find('.dg-wrapper');
this.$items = this.$wrapper.children();
this.itemsCount = this.$items.length;
this.$nav = this.$el.find('nav');
this.$navPrev = this.$nav.find('.dg-prev');
this.$navNext = this.$nav.find('.dg-next');
// minimum of 3 items
if( this.itemsCount < 3 ) {
this.$nav.remove();
return false;
}
this.current = this.options.current;
this.isAnim = false;
this.$items.css({
'opacity' : 0,
'visibility': 'hidden'
});
this._validate();
this._layout();
// load the events
this._loadEvents();
// slideshow
if( this.options.autoplay ) {
this._startSlideshow();
}
},
_validate : function() {
if( this.options.current < 0 || this.options.current > this.itemsCount - 1 ) {
this.current = 0;
}
},
_layout : function() {
// current, left and right items
this._setItems();
// current item is not changed
// left and right one are rotated and translated
var leftCSS, rightCSS, currentCSS;
if( this.support3d && this.supportTrans ) {
leftCSS = {
'-webkit-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'-moz-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'-o-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'-ms-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)'
};
rightCSS = {
'-webkit-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'-moz-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'-o-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'-ms-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)'
};
leftCSS.opacity = 1;
leftCSS.visibility = 'visible';
rightCSS.opacity = 1;
rightCSS.visibility = 'visible';
}
else if( this.support2d && this.supportTrans ) {
leftCSS = {
'-webkit-transform' : 'translate(-350px) scale(0.8)',
'-moz-transform' : 'translate(-350px) scale(0.8)',
'-o-transform' : 'translate(-350px) scale(0.8)',
'-ms-transform' : 'translate(-350px) scale(0.8)',
'transform' : 'translate(-350px) scale(0.8)'
};
rightCSS = {
'-webkit-transform' : 'translate(350px) scale(0.8)',
'-moz-transform' : 'translate(350px) scale(0.8)',
'-o-transform' : 'translate(350px) scale(0.8)',
'-ms-transform' : 'translate(350px) scale(0.8)',
'transform' : 'translate(350px) scale(0.8)'
};
currentCSS = {
'z-index' : 999
};
leftCSS.opacity = 1;
leftCSS.visibility = 'visible';
rightCSS.opacity = 1;
rightCSS.visibility = 'visible';
}
this.$leftItm.css( leftCSS || {} );
this.$rightItm.css( rightCSS || {} );
this.$currentItm.css( currentCSS || {} ).css({
'opacity' : 1,
'visibility': 'visible'
}).addClass('dg-center');
},
_setItems : function() {
this.$items.removeClass('dg-center');
this.$currentItm = this.$items.eq( this.current );
this.$leftItm = ( this.current === 0 ) ? this.$items.eq( this.itemsCount - 1 ) : this.$items.eq( this.current - 1 );
this.$rightItm = ( this.current === this.itemsCount - 1 ) ? this.$items.eq( 0 ) : this.$items.eq( this.current + 1 );
if( !this.support3d && this.support2d && this.supportTrans ) {
this.$items.css( 'z-index', 1 );
this.$currentItm.css( 'z-index', 999 );
}
// next & previous items
if( this.itemsCount > 3 ) {
// next item
this.$nextItm = ( this.$rightItm.index() === this.itemsCount - 1 ) ? this.$items.eq( 0 ) : this.$rightItm.next();
this.$nextItm.css( this._getCoordinates('outright') );
// previous item
this.$prevItm = ( this.$leftItm.index() === 0 ) ? this.$items.eq( this.itemsCount - 1 ) : this.$leftItm.prev();
this.$prevItm.css( this._getCoordinates('outleft') );
}
},
_loadEvents : function() {
var _self = this;
this.$navPrev.on( 'click.gallery', function( event ) {
if( _self.options.autoplay ) {
clearTimeout( _self.slideshow );
_self.options.autoplay = false;
}
_self._navigate('prev');
return false;
});
this.$navNext.on( 'click.gallery', function( event ) {
if( _self.options.autoplay ) {
clearTimeout( _self.slideshow );
_self.options.autoplay = false;
}
_self._navigate('next');
return false;
});
this.$wrapper.on( 'webkitTransitionEnd.gallery transitionend.gallery OTransitionEnd.gallery', function( event ) {
_self.$currentItm.addClass('dg-center');
_self.$items.removeClass('dg-transition');
_self.isAnim = false;
});
},
_getCoordinates : function( position ) {
if( this.support3d && this.supportTrans ) {
switch( position ) {
case 'outleft':
return {
'-webkit-transform' : 'translateX(-450px) translateZ(-300px) rotateY(45deg)',
'-moz-transform' : 'translateX(-450px) translateZ(-300px) rotateY(45deg)',
'-o-transform' : 'translateX(-450px) translateZ(-300px) rotateY(45deg)',
'-ms-transform' : 'translateX(-450px) translateZ(-300px) rotateY(45deg)',
'transform' : 'translateX(-450px) translateZ(-300px) rotateY(45deg)',
'opacity' : 0,
'visibility' : 'hidden'
};
break;
case 'outright':
return {
'-webkit-transform' : 'translateX(450px) translateZ(-300px) rotateY(-45deg)',
'-moz-transform' : 'translateX(450px) translateZ(-300px) rotateY(-45deg)',
'-o-transform' : 'translateX(450px) translateZ(-300px) rotateY(-45deg)',
'-ms-transform' : 'translateX(450px) translateZ(-300px) rotateY(-45deg)',
'transform' : 'translateX(450px) translateZ(-300px) rotateY(-45deg)',
'opacity' : 0,
'visibility' : 'hidden'
};
break;
case 'left':
return {
'-webkit-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'-moz-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'-o-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'-ms-transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'transform' : 'translateX(-350px) translateZ(-200px) rotateY(45deg)',
'opacity' : 1,
'visibility' : 'visible'
};
break;
case 'right':
return {
'-webkit-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'-moz-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'-o-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'-ms-transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'transform' : 'translateX(350px) translateZ(-200px) rotateY(-45deg)',
'opacity' : 1,
'visibility' : 'visible'
};
break;
case 'center':
return {
'-webkit-transform' : 'translateX(0px) translateZ(0px) rotateY(0deg)',
'-moz-transform' : 'translateX(0px) translateZ(0px) rotateY(0deg)',
'-o-transform' : 'translateX(0px) translateZ(0px) rotateY(0deg)',
'-ms-transform' : 'translateX(0px) translateZ(0px) rotateY(0deg)',
'transform' : 'translateX(0px) translateZ(0px) rotateY(0deg)',
'opacity' : 1,
'visibility' : 'visible'
};
break;
};
}
else if( this.support2d && this.supportTrans ) {
switch( position ) {
case 'outleft':
return {
'-webkit-transform' : 'translate(-450px) scale(0.7)',
'-moz-transform' : 'translate(-450px) scale(0.7)',
'-o-transform' : 'translate(-450px) scale(0.7)',
'-ms-transform' : 'translate(-450px) scale(0.7)',
'transform' : 'translate(-450px) scale(0.7)',
'opacity' : 0,
'visibility' : 'hidden'
};
break;
case 'outright':
return {
'-webkit-transform' : 'translate(450px) scale(0.7)',
'-moz-transform' : 'translate(450px) scale(0.7)',
'-o-transform' : 'translate(450px) scale(0.7)',
'-ms-transform' : 'translate(450px) scale(0.7)',
'transform' : 'translate(450px) scale(0.7)',
'opacity' : 0,
'visibility' : 'hidden'
};
break;
case 'left':
return {
'-webkit-transform' : 'translate(-350px) scale(0.8)',
'-moz-transform' : 'translate(-350px) scale(0.8)',
'-o-transform' : 'translate(-350px) scale(0.8)',
'-ms-transform' : 'translate(-350px) scale(0.8)',
'transform' : 'translate(-350px) scale(0.8)',
'opacity' : 1,
'visibility' : 'visible'
};
break;
case 'right':
return {
'-webkit-transform' : 'translate(350px) scale(0.8)',
'-moz-transform' : 'translate(350px) scale(0.8)',
'-o-transform' : 'translate(350px) scale(0.8)',
'-ms-transform' : 'translate(350px) scale(0.8)',
'transform' : 'translate(350px) scale(0.8)',
'opacity' : 1,
'visibility' : 'visible'
};
break;
case 'center':
return {
'-webkit-transform' : 'translate(0px) scale(1)',
'-moz-transform' : 'translate(0px) scale(1)',
'-o-transform' : 'translate(0px) scale(1)',
'-ms-transform' : 'translate(0px) scale(1)',
'transform' : 'translate(0px) scale(1)',
'opacity' : 1,
'visibility' : 'visible'
};
break;
};
}
else {
switch( position ) {
case 'outleft' :
case 'outright' :
case 'left' :
case 'right' :
return {
'opacity' : 0,
'visibility' : 'hidden'
};
break;
case 'center' :
return {
'opacity' : 1,
'visibility' : 'visible'
};
break;
};
}
},
_navigate : function( dir ) {
if( this.supportTrans && this.isAnim )
return false;
this.isAnim = true;
switch( dir ) {
case 'next' :
this.current = this.$rightItm.index();
// current item moves left
this.$currentItm.addClass('dg-transition').css( this._getCoordinates('left') );
// right item moves to the center
this.$rightItm.addClass('dg-transition').css( this._getCoordinates('center') );
// next item moves to the right
if( this.$nextItm ) {
// left item moves out
this.$leftItm.addClass('dg-transition').css( this._getCoordinates('outleft') );
this.$nextItm.addClass('dg-transition').css( this._getCoordinates('right') );
}
else {
// left item moves right
this.$leftItm.addClass('dg-transition').css( this._getCoordinates('right') );
}
break;
case 'prev' :
this.current = this.$leftItm.index();
// current item moves right
this.$currentItm.addClass('dg-transition').css( this._getCoordinates('right') );
// left item moves to the center
this.$leftItm.addClass('dg-transition').css( this._getCoordinates('center') );
// prev item moves to the left
if( this.$prevItm ) {
// right item moves out
this.$rightItm.addClass('dg-transition').css( this._getCoordinates('outright') );
this.$prevItm.addClass('dg-transition').css( this._getCoordinates('left') );
}
else {
// right item moves left
this.$rightItm.addClass('dg-transition').css( this._getCoordinates('left') );
}
break;
};
this._setItems();
if( !this.supportTrans )
this.$currentItm.addClass('dg-center');
},
_startSlideshow : function() {
var _self = this;
this.slideshow = setTimeout( function() {
_self._navigate( 'next' );
if( _self.options.autoplay ) {
_self._startSlideshow();
}
}, this.options.interval );
},
destroy : function() {
this.$navPrev.off('.gallery');
this.$navNext.off('.gallery');
this.$wrapper.off('.gallery');
}
};
var logError = function( message ) {
if ( this.console ) {
console.error( message );
}
};
$.fn.gallery = function( options ) {
if ( typeof options === 'string' ) {
var args = Array.prototype.slice.call( arguments, 1 );
this.each(function() {
var instance = $.data( this, 'gallery' );
if ( !instance ) {
logError( "cannot call methods on gallery prior to initialization; " +
"attempted to call method '" + options + "'" );
return;
}
if ( !$.isFunction( instance[options] ) || options.charAt(0) === "_" ) {
logError( "no such method '" + options + "' for gallery instance" );
return;
}
instance[ options ].apply( instance, args );
});
}
else {
this.each(function() {
var instance = $.data( this, 'gallery' );
if ( !instance ) {
$.data( this, 'gallery', new $.Gallery( options, this ) );
}
});
}
return this;
};
})( jQuery );
$(function() {
$('#dg-container').gallery({
autoplay : true
});
});
答案 0 :(得分：2)
这是设置计时器的功能。经过设定的时间后，setTimeout内的代码再次触发。这是你想要回调的地方。我只是检查回调函数是否存在，如果是，则触发。
_startSlideshow : function() {
var _self = this;
this.slideshow = setTimeout( function() {
_self._navigate( 'next' );
if (_self.options.cb) {
_self.options.cb();
}
if( _self.options.autoplay ) {
_self._startSlideshow();
}
}, this.options.interval );
},
现在您可以将回调作为选项传递：
$('#dg-container').gallery({
autoplay : true,
cb : function() {
console.log('callback fired!');
}
});
如果要在转换的后沿进行回调，请在动画结束时触发回调。这个插件使用的是css动画。当css动画结束时，浏览器会触发事件。这一部分正在对该事件发起一个函数。
this.$wrapper.on( 'webkitTransitionEnd.gallery transitionend.gallery OTransitionEnd.gallery', function( event ) {
_self.$currentItm.addClass('dg-center');
_self.$items.removeClass('dg-transition');
_self.isAnim = false;
if (_self.options.cb) {
_self.options.cb();
}
});