如何从服务器BrainTree获取令牌

Question

如何从我的服务器获取令牌？我进行了简单的过程，只需让令牌出现在我的服务器上，但现在我不知道如何将其下拉并在我的Android应用程序中使用它。这是Braintree建议的方法，当我复制并粘贴它时，它会出现错误。我设法通过他们，但我必须实施一些我认为不对的方法。

我需要做的就是获取客户端令牌并在我的应用中用作变量。有人请帮忙。附：我是Android开发人员的新手。

import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import com.loopj.android.http.*;
import com.braintreepayments.api.dropin.BraintreePaymentActivity;

import org.apache.http.Header;


public class MainActivity extends ActionBarActivity {


    private int REQUEST_CODE;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }
    AsyncHttpClient client = new AsyncHttpClient();

    public void fetchClientToken() {
        client.get("http://clomes.com/clomes/braintree/customer/gettoken", new TextHttpResponseHandler() {
            public String clientToken;

            @Override
            public void onFailure(int i, Header[] headers, String s, Throwable throwable) {

            }

            @Override
            public void onSuccess(int i, Header[] headers, String clientToken) {
                this.clientToken = clientToken;
            }
        });


    }



    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}