我使用android中的JSONarray从远程服务器获取AsyncTask。
AsyncTask有效，我从远程获取JSONarray。
JSONarray看起来像这样。
{
"code": 1,
"auth_key": null,
"gps_key": null,
"status": "Success",
"message": null,
"data": null,
"result": {
"sehedule": [
{
"schedule_id": 2,
"schedule_date": "2015-07-17 00:00:00",
"schedule_name": "Test Schedule"
},
{
"schedule_id": 5,
"schedule_date": "2015-07-18 00:00:00",
"schedule_name": "Another Test Schedule"
}
],
"visit": [
{
"visit_id": 4,
"schedule_id": 2,
"visit_name": "Keels Colombo Branch",
"visit_time": "2017-07-17 10:34:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
},
{
"visit_id": 5,
"schedule_id": 2,
"visit_name": "Keels Gall Branch",
"visit_time": "2017-07-17 11:34:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
},
{
"visit_id": 6,
"schedule_id": 2,
"visit_name": "Keels Kadawatha Branch",
"visit_time": "2017-07-17 13:34:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
},
{
"visit_id": 7,
"schedule_id": 2,
"visit_name": "Keels Homagama Branch",
"visit_time": "2017-07-17 16:34:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
},
{
"visit_id": 8,
"schedule_id": 5,
"visit_name": "Keels Nugegoda Branch",
"visit_time": "2017-07-18 10:15:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
},
{
"visit_id": 9,
"schedule_id": 5,
"visit_name": "Keels Colombo Branch",
"visit_time": "2017-07-18 10:34:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
},
{
"visit_id": 10,
"schedule_id": 5,
"visit_name": "Keels Gall Branch",
"visit_time": "2017-07-18 10:34:00",
"visit_place": "Keels Colombo Branch",
"visit_address": "No 30\\Keels\\Colombo",
"visit_location_lat": "80.123456",
"visit_location_lng": "6.123456",
"visit_status": 0
}
],
"item": [
{
"item_id": 2,
"visit_id": 4,
"item_name": "Check Something"
},
{
"item_id": 3,
"visit_id": 4,
"item_name": "Check Anothrtthing"
},
{
"item_id": 4,
"visit_id": 5,
"item_name": "Check Something"
},
{
"item_id": 5,
"visit_id": 5,
"item_name": "Check Anothrtthing"
},
{
"item_id": 6,
"visit_id": 6,
"item_name": "Check Something"
},
{
"item_id": 7,
"visit_id": 6,
"item_name": "Check Anothrtthing"
},
{
"item_id": 8,
"visit_id": 7,
"item_name": "Check Something"
},
{
"item_id": 9,
"visit_id": 7,
"item_name": "Check Anothrtthing"
},
{
"item_id": 10,
"visit_id": 8,
"item_name": "Check Something"
},
{
"item_id": 11,
"visit_id": 8,
"item_name": "Check Anothrtthing"
},
{
"item_id": 12,
"visit_id": 9,
"item_name": "Check Something"
},
{
"item_id": 13,
"visit_id": 9,
"item_name": "Check Anothrtthing"
},
{
"item_id": 14,
"visit_id": 10,
"item_name": "Check Something"
},
{
"item_id": 15,
"visit_id": 10,
"item_name": "Check Anothrtthing"
}
]
},
"request_date_time": "2015-07-09 10:59:41"
}
尝试从此数组中获取计划列表，并逐个显示在Toast消息中。
public class mainmenu extends Activity {
private String storedkey;
private String jsonfromapi;
private JSONArray Data;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mainmenu);
//loading schedule list
Button btn_sche = (Button) findViewById(R.id.btn_schedule);
btn_sche.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startActivity(new Intent(mainmenu.this, Schedule_Activity.class));
}
});
//loading reset password
Button reset = (Button) findViewById(R.id.btn_reset_password);
reset.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startActivity(new Intent(mainmenu.this, resetpassword.class));
}
});
//loading google maps
Button location = (Button) findViewById(R.id.btn_location);
location.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startActivity(new Intent(mainmenu.this, My_Location.class));
}
});
try {
String user_name = getdate_from_local();
TextView user = (TextView) findViewById(R.id.lbl_name);
user.setText("Welcome : "+user_name+"\n");
} catch (IOException e) {
e.printStackTrace();
}
//getting schedules from api
get_schedule_list();
//show_error_message(jsonfromapi, "Error Occured!");
JSONObject jsonObj = null;
try {
jsonObj = new JSONObject(jsonfromapi);
} catch (JSONException e) {
Log.v("Error in Parser", " " + e);
}
try{
Data = jsonObj.getJSONArray("sehedule");
for (int i = 0; i < Data.length(); i++) {
JSONObject jsonObj2 = Data.getJSONObject(i);
String date = jsonObj2.getString("schedule_date");
String name=jsonObj2.getString("schedule_name");
Toast.makeText(this, date + " - " + name, Toast.LENGTH_LONG).show();
}
}catch(Exception e)
{
}
}
@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);
}
private String readkeyfromfille() throws IOException {
FileInputStream fis = openFileInput("myappkey.txt");
BufferedInputStream bis = new BufferedInputStream(fis);
StringBuffer b = new StringBuffer();
while(bis.available() !=0){
char c = (char) bis.read();
b.append(c);
}
String Key =b.toString();
return Key;
}
public String getdate_from_local() throws IOException {
storedkey = readkeyfromfille();
byte[] data = Base64.decode(storedkey, Base64.DEFAULT);
String key_in_text = new String(data, "UTF-8");
String[] parts = key_in_text.split(Pattern.quote("|"));
String string1 = parts[0]; // 004
String string2 = parts[1];
return string1;
}
private void get_schedule_list(){
try {
jsonfromapi = new MySchedules().execute(storedkey).get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
private void show_error_message(String data, String title){
new AlertDialog.Builder(this)
.setTitle(title)
.setMessage(data)
.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// continue with delete
}
})
.setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// do nothing
}
})
.setIcon(android.R.drawable.ic_dialog_alert)
.show();
}
//async task to get the schedule, visits, items details from remote database
class MySchedules extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... arg0) {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://172.16.110.3/agent_tracking/index.php/api/rest/get-schedules/");
try {
// Add your data
List<BasicNameValuePair> nameValuePairs = new ArrayList<>(1);
nameValuePairs.add(new BasicNameValuePair("key", arg0[0]));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
String schedule_list = EntityUtils.toString(entity, "UTF-8");
return schedule_list;
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
return null;
}
}
// end of async task
}
有人可以帮助我从JSONArray获取时间表并逐一显示。
答案 0 :(得分：2)
JSONObject jsonObject = new JSONObject(respons); //Here reponse is the yours server response
JSONObject result = jsonObject.getJSONObject("result");
JSONArray sehedule = result.getJSONArray("sehedule");
for(int i=0;i<sehedule.length();i++)
{
String schedule_id = sehedule.getJSONObject(i).getString("schedule_id");
String schedule_date = sehedule.getJSONObject(i).getString("schedule_date");
String schedule_name = sehedule.getJSONObject(i).getString("schedule_name");
Toast.makeText(context,schedule_date+" "+schedule_date+" "+schedule_name,Toast.LENGTH_LONG).show();
}
答案 1 :(得分：1)
AsyncClass doInBackground()将对象返回到其onPostExecute()方法。因此，您必须实施onPostExecute()方法，然后您将获得时间表JSON。
class MySchedules extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... arg0) {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://172.16.110.3/agent_tracking/index.php/api/rest/get-schedules/");
try {
// Add your data
List<BasicNameValuePair> nameValuePairs = new ArrayList<>(1);
nameValuePairs.add(new BasicNameValuePair("key", arg0[0]));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
String schedule_list = EntityUtils.toString(entity, "UTF-8");
return schedule_list;
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
return null;
}
@Override
protected String onPostExecute(String data) {
if(data != null){
jsonfromapi = data; //you would get json data here
//then do parse your json data
}
}
}
// end of async task
答案 2 :(得分：0)
在MySchedules Asynctask中，您必须返回schedule_list，您必须使用OnPostExecute() AsyncTask方法而不是 jsonfromapi 字符串。
所以你的AsyncTask看起来像这样：
class MySchedules extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... arg0) {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://172.16.110.3/agent_tracking/index.php/api/rest/get-schedules/");
try {
// Add your data
List<BasicNameValuePair> nameValuePairs = new ArrayList<>(1);
nameValuePairs.add(new BasicNameValuePair("key", arg0[0]));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
String schedule_list = EntityUtils.toString(entity, "UTF-8");
return schedule_list;
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
return null;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
JSONObject jsonObj = null;
try {
jsonObj = new JSONObject(result);
} catch (JSONException e) {
Log.v("Error in Parser", " " + e);
}
try{
Data = jsonObj.getJSONArray("sehedule");
for (int i = 0; i < Data.length(); i++) {
JSONObject jsonObj2 = Data.getJSONObject(i);
String date = jsonObj2.getString("schedule_date");
String name=jsonObj2.getString("schedule_name");
Toast.makeText(this, date + " - " + name, Toast.LENGTH_LONG).show();
}
}catch(Exception e)
{
}
}
}
答案 3 :(得分：0)
移动尝试解析 MySchedules类中onCreate和postExecute()方法的响应的代码：
class MySchedules extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... arg0) {
... your code that fetched list
}
protected void onPostExecute(String json) {
try {
JSONObject jsonObj = new JSONObject(json);
JSONObject resultObj = jsonObj.getJSONObject("result");
JSONArray jsonArray = resultObj.getJSONArray("schedule");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObj2 = jsonArray.getJSONObject(i);
String date = jsonObj2.getString("schedule_date");
String name = jsonObj2.getString("schedule_name");
Toast.makeText(this, date + " - " + name, Toast.LENGTH_LONG).show();
}
} catch(Exception e) {
Log.e("Error", e.getMessage());
Toast.makeText(this, "Error while parsing response - " + e.getMessage(), Toast.LENGTH_LONG).show();
}
}
}
问题是获取结果的异步任务是在一个单独的线程中执行的，并且解析结果的代码在完成时没有被执行;它试图直接解析结果..
将解析代码放在异步任务的onPostExecute中;在尝试解析json之前，它将等待从服务器获取结果。
您还需要先获得结果＆＃39;在获得＆＃39;计划之前的元素＆＃39;元素（你也错过了＆＃34; sehedule＆＃34;），其中包含日程表对象数组。希望有所帮助：）