我目前的 android 应用程序存在问题,如果我运行应用程序,服务器在线,然后使用后退按钮关闭应用程序,然后关闭服务器然后再次启动应用程序,则会记住 json 响应. 如果我强制退出应用程序,并在服务器关闭的情况下再次运行它,则没有 json 响应。这个响应被缓存在哪里?我通过实例方法调用它以接收此响应,但我不明白为什么会发生这种情况。我怎样才能让我的应用程序不记得这个响应?
在我的活动中:
uFunctions = new JSONFunctions();
JSONObject json = null;
System.out.println(json); // Returns null
json = uFunctions.getJson(uid);
System.out.println(json); //Returns the json after the request was completed
//successfully even if the server is offline afterwards.
JSON函数:
public class JSONFunctions{
public JSONFunctions(){
jParser = new jParser();
}
public JSONObject getJson(String uid){
List<NameValuePair> param = new ArrayList<NameValuePair>();
param.add(new BasicNameValuePair("tag", "request");
param.add(new BasicNameValuePair("id", uid);
JSONObject json = jParser.getJsonFromUrl(url, param);
return json;
}
}
解析器:
public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
Log.e("JSON", json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}