Android线程完成回调

Question

我想在收到服务器响应后执行 http post。如果服务器响应为 false，则 http post 将执行，否则不执行。我该怎么做。

我的安卓主要 Activity 代码:

if (Utility.isValidMobile(mobileNumber)) {
            String isAvailable = userDelegate.checkUser(mobileNumber, context);


            if (isAvailable.equals("false")) {
                userDelegate.addUser(userMO, context);
                Toast.makeText(getApplicationContext(), "Your mobile number is" + mobileNumber + "name is" + userName, Toast.LENGTH_LONG).show();
            } else if (isAvailable.equals("true")) {
                Toast.makeText(getApplicationContext(), "Your mobile number is already registerd", Toast.LENGTH_LONG).show();
            }
        } 

当我点击注册按钮时，上面的代码将被执行

我的 Userdelegate 类代码:

public void addUser(final UserMO userMo, final Context context) {

    final String jsonStringObject = gson.toJson(userMo);

    Thread t = new Thread() {
        public void run() {
            Looper.prepare(); // for the child Thread
            HttpClient client = new DefaultHttpClient();
            HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); // Timeout
                                                                                    // Limit
            try {
                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
                nameValuePairs.add(new BasicNameValuePair("userBO", jsonStringObject));
                HttpPost post = new HttpPost("http://192.168.1.101:8080/warname/user/addUser");
                post.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                HttpResponse response = client.execute(post);
                BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
                Toast.makeText(context, "Your user id " + rd.readLine(), Toast.LENGTH_LONG).show();
            } catch (Exception e) {
                e.printStackTrace();
            }
            Looper.loop(); // Loop in the message queue
        }
    };
    t.start();

}

public void getMatchingExistingUserList(final String mobile_number, final Context context) {

    final String jsonStringObject = gson.toJson(mobile_number);

    Thread t = new Thread() {
        public void run() {
            Looper.prepare(); // for the child Thread
            HttpClient client = new DefaultHttpClient();
            HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); // Timeout
                                                                                    // Limit
            try {
                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
                nameValuePairs.add(new BasicNameValuePair("userBO", jsonStringObject));
                HttpPost post = new HttpPost("http://192.168.1.101:8080/warname/user/addUser");
                post.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                HttpResponse response = client.execute(post);
                BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
                final String responseString = rd.readLine();
            } catch (Exception e) {
                e.printStackTrace();
            }
            Looper.loop(); // Loop in the message queue
        }
    };
    t.start();
}

public String checkUser(final String mobile_number, final Context context) {

    final StringBuilder isAvailable = new StringBuilder();

    Thread t = new Thread() {
        @Override   
        public void run() {
            Looper.prepare(); // for the child Thread
            try {
                HttpClient client = new DefaultHttpClient();
                HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); // Timeout
                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
                nameValuePairs.add(new BasicNameValuePair("MobileNumber", gson.toJson(mobile_number)));
                HttpPost post = new HttpPost("http://192.168.1.101:8080/warname/user/checkUserMobileNumber");
                post.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                HttpResponse response = client.execute(post);
                BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
                isAvailable.append(rd.readLine());
            } catch (Exception e) {
                e.printStackTrace();
            }
            Looper.loop(); // Loop in the message queue
        }
    };
    t.start();
    return isAvailable.toString();
}

问题是我得到的响应是错误的，但 if 条件不起作用。如何解决这个问题。

改变后:

if (Utility.isValidMobile(mobileNumber)) {
            new AsyncTask<Void, Void, String>() {
                @Override
                protected String doInBackground(Void... arg0) {
                    return userDelegate.checkUser(mobileNumber, context);
                }

                @Override
                protected void onPostExecute(String isAvailable) {
                    Toast.makeText(getApplicationContext(), isAvailable, Toast.LENGTH_LONG).show();
                    if (isAvailable.equals("false")) {
                        Toast.makeText(getApplicationContext(), "Your mobile number is" + mobileNumber + "name is" + userName, Toast.LENGTH_LONG).show();
                        userDelegate.addUser(userMO, context);
                    } else if (isAvailable.equals("true")) {
                        Toast.makeText(getApplicationContext(), "Your mobile number is already registerd", Toast.LENGTH_LONG).show();
                    }
                }
            }.execute(null, null, null);
        }

if 条件不工作？

Answer 1

If server response is false the http post will execute else not execute. How can i do for this

出现问题是因为您在 checkUser 中使用线程和 addUser .线程的执行没有停止当前线程的执行。

例如，当checkUser然后从主线程调用方法 final StringBuilder isAvailable = new StringBuilder();在主线程和线程上执行 t正在单独执行。所以系统将控制返回到下一行 return isAvailable.toString();无需等待线程执行完成意味着 checkUser方法总是返回 null或 empty字符串。

同样适用于 addUser方法。

根据checkUser的结果做任务方法响应使用AsyncTask类(class)。