关于post传输,接收返回值的问题.

我有接口,只需要用post将数据传进去,进行比对,然后 由接口返回一个值,
代码如下.
private Button imgB1;
private EditText et1;
private Intent intent;
public ProgressDialog pdialog=null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        imgB1=(Button)findViewById(R.id.reimageButton1);
        et1=(EditText)findViewById(R.id.reeditText1);
        imgB1.setOnClickListener(new Button.OnClickListener(){
         public void onClick(View arg0) {
         //声明网站字符串
         String uriAPI="...";
         //传送的字符
         String username=et1.getText().toString();
         //创建http Post连接
         HttpPost httpRequest=new HttpPost(uriAPI);
         //Post运行传送变量必须用NameValuePair[NameValuePair 
         List<NameValuePair> params=new ArrayList<NameValuePair>();
         params.add(new BasicNameValuePair("str",username));
         try{
         //发送HTTP request
         httpRequest.setEntity(new UrlEncodedFormEntity(params,HTTP.UTF_8));
         //去的HTTP response
         HttpResponse httpResponse=new DefaultHttpClient().execute(httpRequest);
         if(httpResponse.getStatusLine().getStatusCode()==0){
         new AlertDialog.Builder(AsdActivity.this)
                 .setTitle("提示")
                 .setMessage("请求类型不存在")
                 .setPositiveButton("确定", new DialogInterface.OnClickListener() {
        
         public void onClick(DialogInterface dialog, int which) {
         dialog.dismiss();
         pdialog.dismiss();
         }
         })
         .show();
         }else if(httpResponse.getStatusLine().getStatusCode()==1){
         new AlertDialog.Builder(AsdActivity.this)
                 .setTitle("提示")
                 .setMessage("申请账号成功,点击后跳转至首页")
                 .setPositiveButton("确定", new DialogInterface.OnClickListener() {
        
         public void onClick(DialogInterface dialog, int which) {
         intent=new Intent();
         intent.setClass(AsdActivity.this, AsdActivity.class);
         dialog.dismiss();
         pdialog.dismiss();
         startActivity(intent);
//         AsdActivity.this.finish();
         }
         })
         .show();
         }else if(httpResponse.getStatusLine().getStatusCode()==-1){
         new AlertDialog.Builder(AsdActivity.this)
         .setTitle("提示")
         .setMessage("请求参数错误")
         .setPositiveButton("确定", new DialogInterface.OnClickListener() {
        
         public void onClick(DialogInterface dialog, int which) {
         dialog.dismiss();
         pdialog.dismiss();
         }
         })
         .show();
         }else if(httpResponse.getStatusLine().getStatusCode()==-2){
         new AlertDialog.Builder(AsdActivity.this)
         .setTitle("提示")
         .setMessage("该号码已被注册")
         .setPositiveButton("确定", new DialogInterface.OnClickListener() {
        
         public void onClick(DialogInterface dialog, int which) {
         dialog.dismiss();
         pdialog.dismiss();
         }
         })
         .show();
         }
         }catch(Exception e){
         e.printStackTrace();
         }
         }
        });注释: 接口返回的值是一个数字.  1,0 -1,-2 有大侠知道错在哪吗？