react-native app 屏幕适配方案（按照设计稿像素大小写就行）

import React, { Component,PropTypes } from 'react';
import { Dimensions,PixelRatio,Platform,StatusBar,View } from 'react-native';
let props = {};
export default class Resolution {
static get(useFixWidth = true) {
return useFixWidth ? {
...props.fw
} : {
...props.fh
}
}

static setDesignSize(dwidth = 750, dheight = 1336, dim = "window") {
let designSize = {
width: dwidth,
height: dheight
};

let navHeight = Platform.OS === 'android' ? StatusBar.currentHeight : 0;
let pxRatio = PixelRatio.get(dim);
let {
  width,
  height
} = Dimensions.get(dim);
if (dim != "screen") height -= navHeight;
let w = PixelRatio.getPixelSizeForLayoutSize(width);
let h = PixelRatio.getPixelSizeForLayoutSize(height);

let fw_design_scale = designSize.width / w;
fw_width = designSize.width;
fw_height = h * fw_design_scale;
fw_scale = 1 / pxRatio / fw_design_scale;

let fh_design_scale = designSize.height / h;
fh_width = w * fh_design_scale;
fh_height = designSize.height;
fh_scale = 1 / pxRatio / fh_design_scale;

props.fw = {
  width: fw_width,
  height: fw_height,
  scale: fw_scale,
  navHeight
};
props.fh = {
  width: fh_width,
  height: fh_height,
  scale: fh_scale,
  navHeight
};

console.log("winSize", JSON.stringify({
  width,
  height
}))
console.log("winPixelSize", JSON.stringify({
  width: w,
  height: h
}))
console.log("pxRatio", pxRatio)
console.log("fixWidth", JSON.stringify(props.fw))
console.log("fixHeight", JSON.stringify(props.fh))

}

static FixWidthView = (p) => {
let {
width,
height,
scale,
navHeight
} = props.fw;
return ( <
View {
...p
}
style = {
[p.style, {
marginTop: navHeight,
width: width,
height: height,
transform: [{
translateX: -width * .5
},
{
translateY: -height * .5
},
{
scale: scale
},
{
translateX: width * .5
},
{
translateY: height * .5
}
]
}]
}
/>
);
};

static FixHeightView = (p) => {
let {
width,
height,
scale,
navHeight
} = props.fh;
return ( <
View {
...p
}
style = {
[p.style, {
marginTop: navHeight,
width: width,
height: height,
transform: [{
translateX: -width * .5
},
{
translateY: -height * .5
},
{
scale: scale
},
{
translateX: width * .5
},
{
translateY: height * .5
}
]
}]
}
/>
);
};
};
//init
Resolution.setDesignSize();