js 和 Android 交互

// js
window.invokeScanCallBack = function(data) {
  that.$toast(data);
}
window.XZDAndroid.invokeScan('invokeScanCallBack');
// 不用接收回调的
window.XZDAndroid.invokeBack()
window.XZDAndroid.invokeLogin()

// java
public class JavaScriptInterface {

    Context context;
    WebView webView;

    JavaScriptInterface(Context c, WebView w) {
        context = c;
        webView = w;
    }

    public void myFunction(String callback) {
        //when I log callback, it is "undefined"
         String someData = "Yay for data";
         String js =
             "javascript:(function() { "
                 + "var callback = " + callback + ";"
                 + "callback('" + someData + "');"
             + "})()";
        webView.loadUrl(js);
    }
}