原因：在WebViewClient的回调方法onReceivedSslError里只单纯的写了handler.proceed();没给出明确的原因

两种解决方法：

1、去掉WebViewClient的回调方法onReceivedSslError

2、修改onReceivedSslError如下所示

@Override
public void onReceivedSslError(WebView view, final SslErrorHandler handler, SslError error) {AlertDialog.Builder builder = new AlertDialog.Builder(view.getContext());builder.setMessage("SSL认证失败，是否继续访问？");builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {handler.proceed();}});builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {handler.cancel();}});AlertDialog dialog = builder.create();dialog.show();
}