Android 通过 localstorage 向 HTML5 传参

现在的 APP，Android 与 H5 混合开发已很常见。当 Android 通过 WebView 加载 H5 页面，且需要向其传参时，可以用 loaclstorage 来实现。代码如下：
WebView 先要设置如下属性：

 webView.getSettings().setDomStorageEnabled(true);        webView.getSettings().setAppCacheMaxSize(1024*1024*8);        String appCachePath = getApplicationContext().getCacheDir().getAbsolutePath();        webView.getSettings().setAppCachePath(appCachePath);        webView.getSettings().setAllowFileAccess(true);        webView.getSettings().setAppCacheEnabled(true);        JavaScriptInterface jsInterface = new JavaScriptInterface(this);        webView.getSettings().setJavaScriptEnabled(true);        webView.addJavascriptInterface(jsInterface, "JSInterface");

然后，传递参数：

   webView.setWebViewClient(new WebViewClient() {            @Override            public void onPageFinished(WebView view, String url) {               String key = "hello";               String val = "world";               if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {                   webView.evaluateJavascript("localStorage.setItem('"+ key +"','"+ val +"');", null);               } else {                   webView.loadUrl("javascript:localStorage.setItem('"+ key +"','"+ val +"');");               }            }   });

JavaScriptInterface 部分的代码如下：

 public class JavaScriptInterface {        private Activity activity;        public JavaScriptInterface(Activity activiy) {            this.activity = activiy;        }        public string getData(String someParameter){           //also you can return json data as string  and at client side do JSON.parse           if (someParameter == "transmitData" && this.activity.data) {                return this.activity.data;           }else{                return null;           }        }    }

Js 部分的代码如下：

<script>  function ready() {        var data = window.JSInterface.getData("transmitData");        localStorage.put("transmitData", data)  };  document.addEventListener("DOMContentLoaded", ready);</script>