public void evaluateJavascript(final String script) {
        if (Looper.getMainLooper() == Looper.myLooper()) {
            _evaluateJavascript(script);
        } else {
            if (mainThreadHandler != null) {
                Message msg = mainThreadHandler.obtainMessage(EXEC_SCRIPT, script);
                mainThreadHandler.sendMessage(msg);
            }
        }
    }
This method can be called in any thread, and if it is not called in the main thread,
it will be automatically distributed to the main thread.

@param script
app/src/main/java/com/example/jingbin/webviewstudy/view/WVJBWebView.java