WebChromeClient主要辅助WebView处理Javascript的交互以及浏览器层面的事件，下面介绍一些常用的回调方法：

// 拦截Alert弹框
@Override
public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
    return super.onJsAlert(view, url, message, result);
}
//拦截 confirm弹框
@Override
public boolean onJsConfirm(WebView view, String url, String message, JsResult result) {
    return super.onJsConfirm(view, url, message, result);
}
//拦截prompt弹框
@Override
public boolean onJsPrompt(WebView view, String url, String message, String defaultValue, JsPromptResult result) {
    return super.onJsPrompt(view, url, message, defaultValue, result);
}
// 打印console信息
@Override
public boolean onConsoleMessage(ConsoleMessage consoleMessage) {
    return super.onConsoleMessage(consoleMessage);
}
// 页面加载进度
@Override
public void onProgressChanged(WebView view, int newProgress) {
    super.onProgressChanged(view, newProgress);
}