Android WebView加载网页后一片空白

很可能是SSL证书存在问题导致网页无法加载，应该在设置WebViewClient并且在WebViewClient中重写onReceivedSslError，创建一个弹框，让用户选择是否继续信任该网站，如下：

mWebView.setWebViewClient(new WebViewClient() {
	           @Override
            public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
                final AlertDialog.Builder builder = new AlertDialog.Builder(view.getContext());
                String message = "SSL Certificate error.";
                switch (error.getPrimaryError()) {
                    case SslError.SSL_UNTRUSTED:
                        message = "The certificate authority is not trusted.";
                        break;
                    case SslError.SSL_EXPIRED:
                        message = "The certificate has expired.";
                        break;
                    case SslError.SSL_IDMISMATCH:
                        message = "The certificate Hostname mismatch.";
                        break;
                    case SslError.SSL_NOTYETVALID:
                        message = "The certificate is not yet valid.";
                        break;
                    default:
                        break;
                }
                message += " Do you want to continue anyway?";

                builder.setTitle("SSL Certificate Error");
                builder.setMessage(message);
                builder.setPositiveButton("continue", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        handler.proceed();
                    }
                });
                builder.setNegativeButton("cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        handler.cancel();
                    }
                });
                final AlertDialog dialog = builder.create();
                dialog.show();
            }
}