Activity activity = BaseActivity.getCurrentActivity();
        View view = LayoutInflater.from(activity).inflate(R.layout.no_net_connected_layout, null);
        AlertDialog.Builder builder = new AlertDialog.Builder(activity);
        builder.setView(view);
        final AlertDialog alertDialog = builder.show();
        alertDialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);(添加这行代码即可)
        view.findViewById(R.id.rl_no_net_connect_custom_dialog).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (alertDialog != null) {
                    alertDialog.dismiss();
                }
            }
        });

        view.findViewById(R.id.tv_retry_no_net_connected_custom_dialog).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (alertDialog != null) {
                    alertDialog.dismiss();
                }
            }
        });
    }
});