tg-turing
Version:
turing components
61 lines (60 loc) • 2.39 kB
JavaScript
/*
# 按照宽高比例设定html字体, width=device-width initial-scale=1版
# @pargam win 窗口window对象
# @pargam option{
designWidth: 设计稿宽度，必须
designHeight: 设计稿高度，不传的话则比例按照宽度来计算，可选
designFontSize: 设计稿宽高下用于计算的字体大小，默认20，可选
callback: 字体计算之后的回调函数，可选
}
# return Boolean;
# xiaoweili@tencent.com
# ps:请尽量第一时间运行此js计算字体
*/
!function(win, option) {
var count = 0,
designWidth = option.designWidth,
designHeight = option.designHeight || 0,
designFontSize = option.designFontSize || 20,
callback = option.callback || null,
root = document.documentElement,
body = document.body,
rootWidth, newSize, t, self;
root.style.width = "100%";
//返回root元素字体计算结果
function _getNewFontSize() {
var scale = designHeight !== 0 ? Math.min(win.innerWidth / designWidth, win.innerHeight / designHeight) : win.innerWidth / designWidth;
return parseInt( scale * 10000 * designFontSize ) / 10000;
}
!function () {
rootWidth = root.getBoundingClientRect().width;
self = self ? self : arguments.callee;
//如果此时屏幕宽度不准确，就尝试再次获取分辨率，只尝试20次，否则使用win.innerWidth计算
if( rootWidth !== win.innerWidth && count < 20 ) {
win.setTimeout(function () {
count++;
self();
}, 0);
} else {
newSize = _getNewFontSize();
//如果css已经兼容当前分辨率就不管了
if( newSize + 'px' !== getComputedStyle(root)['font-size'] ) {
root.style.fontSize = newSize + "px";
return callback && callback(newSize);
}
}
}();
//横竖屏切换的时候改变fontSize，根据需要选择使用
win.addEventListener("onorientationchange" in window ? "orientationchange" : "resize", function() {
clearTimeout(t);
t = setTimeout(function () {
self();
}, 300);
}, false);
}(window, {
designWidth: 640,
designHeight: 1136,
designFontSize: 20,
callback: function (argument) {
}
});