我有用于在用户向下滚动页面时更改背景颜色的代码。
前两个div的背景颜色会发生变化。如何调用该函数再次运行,以便第三个div背景颜色变为开始颜色?
function call(){
$(document).scroll(function() {
scroll_pos = $(this).scrollTop();
if(scroll_pos >= animation_begin_pos && scroll_pos <= animation_end_pos ) {
var percentScrolled = scroll_pos / ( animation_end_pos - animation_begin_pos );
var newRed = beginning_color.red() + ( ( ending_color.red() - beginning_color.red() ) * percentScrolled );
var newGreen = beginning_color.green() + ( ( ending_color.green() - beginning_color.green() ) * percentScrolled );
var newBlue = beginning_color.blue() + ( ( ending_color.blue() - beginning_color.blue() ) * percentScrolled );
var newColor = new $.Color( newRed, newGreen, newBlue );
//console.log( newColor.red(), newColor.green(), newColor.blue() );
$('body').animate({ backgroundColor: newColor }, 0);
} else if ( scroll_pos > animation_end_pos ) {
$('body').animate({ backgroundColor: ending_color }, 0);
} else if ( scroll_pos < animation_begin_pos ) {
$('body').animate({ backgroundColor: beginning_color }, 0);
} else { }
});
}
答案 0 :(得分:0)
请参阅:http://jsfiddle.net/Khursheed_Ali/Phb4B/26 /
代码:
function call(){
var offset=0;
$(document).scroll(function() {
scroll_pos = $(this).scrollTop();
if(scroll_pos >= animation_begin_pos && scroll_pos <= animation_end_pos ) {
// console.log( 'scrolling and animating' );
//we want to calculate the relevant transitional rgb value
var percentScrolled = (scroll_pos-offset) / ( animation_end_pos - animation_begin_pos );
var newRed = beginning_color.red() + ( ( ending_color.red() - beginning_color.red() ) * percentScrolled );
var newGreen = beginning_color.green() + ( ( ending_color.green() - beginning_color.green() ) * percentScrolled );
var newBlue = beginning_color.blue() + ( ( ending_color.blue() - beginning_color.blue() ) * percentScrolled );
var newColor = new $.Color( newRed, newGreen, newBlue );
//console.log( newColor.red(), newColor.green(), newColor.blue() );
$('body').animate({ backgroundColor: newColor }, 0);
} else if ( scroll_pos > animation_end_pos ) {
$('body').animate({ backgroundColor: ending_color }, 0);
} else if ( scroll_pos < animation_begin_pos ) {
$('body').animate({ backgroundColor: beginning_color }, 0);
} else { }
// added
if(scroll_pos > animation_end_pos){
offset+=blocks *2;
animation_begin_pos=animation_end_pos; animation_end_pos+=blocks *2;
$('body').animate({ backgroundColor: beginning_color }, 0);
}
if(scroll_pos<offset){
console.log("offset:"+offset)
offset-=blocks *2;
animation_end_pos-=blocks *2; animation_begin_pos-=blocks *2;
}
});
答案 1 :(得分:0)
这是你可能想要的。 JsFiddle Link
我刚换了一行。
var animation_end_pos = blocks + blocks;
到
var animation_end_pos = blocks * $('.block').length;
动画应该在最后一个块而不是第二个块结束,所以我计算了总高度(所有块的高度之和。这里假设所有块的高度都相同。)
var blocks = $(".block").height();
...
var animation_end_pos = blocks * $('.block').length;
为了获得更好的效果,我在页面加载时将body的背景颜色设置为开始颜色。
$("body").css("background-color", beginning_color);
答案 2 :(得分:0)
我刚换了一行。
var animation_end_pos = blocks + blocks;
到
var animation_end_pos = blocks * $('.block').length;
动画应该在最后一个块而不是第二个块结束,所以我计算了总高度(所有块的高度之和。这里假设所有块的高度都相同。)
var blocks = $(".block").height();
...
var animation_end_pos = blocks * $('.block').