2

请告知为什么如果我尝试获取数组的长度，我的小应用程序总是会出错。

请在下面找到我的代码：

1. 字符串解析器

    package dl.data.background;

    import java.util.ArrayList;
        public class StringParser {

        public StringParser()
        {

        }

        public ArrayList<Object> Parse (String input) {
            ArrayList<Object> output = new ArrayList <Object>();

            int pointer = 0;
            String data = "";

            while (pointer <= input.length()-1)
            {
                if(input.charAt(pointer) == '#'){
                    output.add(data);
                    data = "";
                    pointer++;
                }
                if(pointer < input.length())
                {
                    data += input.charAt(pointer);
                }
                pointer++;
            }
            return output;
        }
    }

2. 下载数据

    package dl.data.background;

    import java.io.BufferedReader;
    import java.io.InputStream;
    import java.io.InputStreamReader;
    import java.util.ArrayList;

    import org.apache.http.HttpResponse;
    import org.apache.http.client.methods.HttpGet;
    import org.apache.http.impl.client.DefaultHttpClient;

    import android.app.Activity;
    import android.os.AsyncTask;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.TextView;

    public class BackgroundDataActivity extends Activity {
    private TextView textView;



    /** Called when the activity is first created. */

    @Override
    public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    textView = (TextView) findViewById(R.id.TextView01);

    }

    private class DownloadWebPageTask extends AsyncTask<String, Void, String> {
    @Override
    protected String doInBackground(String... urls) {
      String response = "";
      for (String url : urls) {
        DefaultHttpClient client = new DefaultHttpClient();
        HttpGet httpGet = new HttpGet(url);
        try {
          HttpResponse execute = client.execute(httpGet);
          InputStream content = execute.getEntity().getContent();

          BufferedReader buffer = new BufferedReader(new InputStreamReader(content));
          String s = "";
          while ((s = buffer.readLine()) != null) {
            response += s;
          }

        } catch (Exception e) {
          e.printStackTrace();
        }
      }
      return response;
    }

    protected void onPostExecute(String result) {
        StringParser stringParser = new StringParser();
            ArrayList<Object> arrayList = stringParser.Parse(result);

            Object [] output = arrayList.toArray();

            // how to get length of output array?? 
        textView.setText(output.length);

      }
    }

    public void readWebpage(View view) {
      DownloadWebPageTask task = new DownloadWebPageTask();
      String url1 = "http://atmbersama.16mb.com/atmlocator.php?ct=SEL_Id&lat=-6.302161&lng=106.743679&radius=20";

      task.execute(new String[] {url1});
       }
     }

如何获得输出数组的长度？？ 

textView.setText(output.length);
4

1 回答 1

8

length是一个Integer，并且setText(CharSequence)期望一个CharSequence：

textView.setText(String.valueOf(output.length));

代码编译得很好，因为实际上有一个重载方法setText(int resid)实际上需要一个整数。但是，此方法将尝试加载具有给定 id 的资源。

于 2012-09-18T17:43:46.790 回答