Actually in my project, I'm blocked. So, for the first time I ask the community of Stackoverflow. I'm new in development.
So, I have a MySql with my datas and I wan't to see in my application the items of users.
For that, I've this :
public class SuccessActivity extends AppCompatActivity {
public static final int CONNECTION_TIMEOUT = 10000;
public static final int READ_TIMEOUT = 15000;
private ListView listView;
protected String meubles[] = new String[100];
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_success);
Intent intent = getIntent();
String id = intent.getStringExtra("id");
this.listView = (ListView) findViewById(R.id.liste);
new SuccessActivity.Recup().execute(id);
}
//PRIVATE CLASSE POUR AFFICHER LES MEUBLES
private class Recup extends AsyncTask<String, String, String> {
HttpURLConnection conn;
URL url = null;
#Override
protected String doInBackground(String... params) {
try {
//url d'ou reside mon fichier php
url = new URL("http://opix-dev.fr/mytinyhomme/personne/afficher.meuble.php");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return "exception";
}
try {
// parametrage du HttpURLConnection pour recevoir et envoyer des donner à mysql
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("POST");
// setDoInput and setDoOutput method depict handling of both send and receive
conn.setDoInput(true);
conn.setDoOutput(true);
// Append parameters to URL
Uri.Builder builder = new Uri.Builder()
.appendQueryParameter("id", params[0]);
String query = builder.build().getEncodedQuery();
// Open connection for sending data
OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write(query);
writer.flush();
writer.close();
os.close();
conn.connect();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return "exception";
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made
if (response_code == HttpURLConnection.HTTP_OK) {
// Read data sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
StringBuilder result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
// Pass data to onPostExecute method
return (result.toString());
} else {
return ("unsuccessful");
}
} catch (IOException e) {
e.printStackTrace();
return "exception";
} finally {
conn.disconnect();
}
}
#Override
protected void onPostExecute(String resulta) {
//this method will be running on UI thread
if (resulta.equalsIgnoreCase("false")) {
} else if (resulta.equalsIgnoreCase("exception") || resulta.equalsIgnoreCase("unsuccessful")) {
} else {
try {
JSONArray nom = new JSONArray(resulta);
System.out.println(nom);
String meubles[] = new String[100];
for (int i = 0; i < nom.length(); i++){
JSONObject jsonobject = nom.getJSONObject(i);
meubles[i]= jsonobject.getString("nom");
System.out.println(jsonobject);
System.out.println(meubles);
item.setText( meubles[i]);
}
System.out.println(meubles);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
}
The file.php is correct because the JSONArray in System.print is ok But I've try with some TextView for display the board at the end, but I did not succeed.
How I can use the meuble[0] , meuble[1], meuble[2](it's board of String name of items) in a ListView ?
Here is what you need to do to show your data in a listview,
Modified onPostExecute() method:
#Override
protected void onPostExecute(String resulta) {
//this method will be running on UI thread
if (resulta.equalsIgnoreCase("false")) {
} else if (resulta.equalsIgnoreCase("exception") || resulta.equalsIgnoreCase("unsuccessful")) {
} else {
try {
JSONArray nom = new JSONArray(resulta);
System.out.println(nom);
String meubles[] = new String[100];
for (int i = 0; i < nom.length(); i++){
JSONObject jsonobject = nom.getJSONObject(i);
meubles[i]= jsonobject.getString("nom");
System.out.println(jsonobject);
System.out.println(meubles);
}
ArrayAdapter<String> listAdapter=new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,meubles);
listView.setAdapter(listAdapter);
System.out.println(meubles);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
What's added?
You need an adapter to show items in a listview. You can create your custom adapter class by extending an arrayadapter or you can use an arrayadapter without customizing it as shown.
Added code:
Create a new adapter,
ArrayAdapter listAdapter=new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,list);
Set adapter for your listview,
listView.setAdapter(listAdapter);
Related
I try to create synchronized threads, but I always get the following error: android.os.NetworkOnMainThreadException.
I've read more posts, but they don't work for me.
Below I write the code blocks that do not work for me:
1.
final SyncApp syncJob = new SyncApp();
Thread t = new Thread (new Runnable () {
#Override
public void run () {
synchronized (syncJob) {
String s = syncJob.insert (newJobs, GlobalVariables.URL_LOCALHOST + "jobs");
txtState.setText (s);
}}});
}
});
t.Start ();
// t.run ();
2.
myClass.runOnUiThread(new Runnable() {
public void run() {...}
})
3.
Running code in main thread from another thread
SyncApp:
public class SyncApp {
synchronized public String insert(List<Jobs> job, String... params) {
URL url = null;
HttpURLConnection conn = null;
try {
url = new URL(params[0]);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json");
conn.setDoInput(true);
conn.setDoOutput(true);
String str = new Gson().toJson(job);
byte[] outputInBytes = str.getBytes();
OutputStream os = conn.getOutputStream();
os.write( outputInBytes );
os.flush();
int responseCode=conn.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
String line;
BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line=br.readLine()) != null) {
response+=line;
}
}
else {
response=conn.getResponseMessage();
}
return response;
} catch (Exception e) {
e.printStackTrace();
} finally {
conn.disconnect();
}
return null;
}
}
I need to call a thread, wait for the answer and call another thread. Their answers I must use them in the activity
I need to call a thread, wait for the answer and call another thread.
Their answers I must use them in the activity
Example using async tasks to accomplish objective.
In this code, let A be your activity which needs to call a thread,
wait for the answer and call another thread. Customize as needed.
Since you never wait in UI threads, callbacks are used to accomplish synchronization.
Let A be your activity class:
public class A extends Activity {
// some method in activity where you launch a background thread (B)
// which then completes and invokes callback which then creates and launches
// a background thread (C) which then completes and invokes a callback.
//
// In callback C, you are on the UI thread.
protected void someMethod() {
new B(new B.CallbackB() {
public void result(Object o) {
new C(new C.CallbackC() {
public void result(Object o, Object answerFromB) {
// OK - C is now done and we are on UI thread!
// 'o' is answer from C
// 'answerFromB' also provided
}
}, o).execute(new Object());
}
).execute(new Object());
}
}
Define a class B:
public class B extends AsyncTask<Object, Void, Object> {
public static interface CallbackB {
void result(Object o);
}
private CallbackB cb;
public B (CallbackB cb) {
this.cb = cb;
}
protected Object doInBackground(Object... params) {
// do work and return an answer.
return new Object();
}
protected void onPostExecute(Object result) {
if (cb != null) {
cb.result(result);
}
}
}
Define a class C:
public class C extends AsyncTask<Object, Void, Object> {
public static interface CallbackC {
void result(Object o, Object answerFromB);
}
private CallbackC cb;
private Object answerFromB;
public C (CallbackC cb, Object answerFromB) {
this.cb = cb;
this.answerFromB = answerFromB;
}
protected Object doInBackground(Object... params) {
// do work and return an answer.
return new Object();
}
protected void onPostExecute(Object result) {
if (cb != null) {
cb.result(result, answerFromB);
}
}
}
For reference:
https://stackoverflow.com/a/9963705/2711811
My solution is:
public class Sync extends AppCompatActivity {
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sync_server);
dao = new DAO(this);
txtState = findViewById(R.id.txt_log);
btnSincro = findViewById(R.id.btn_sincro);
btnSincro.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
countCall = 0;
callFlow();
}
});
btnHome = findViewById(R.id.btn_home);
btnHome.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(SyncServerActivity.this, MainActivity.class);
startActivity(intent);
}
});
}
private void callFlow() {
switch (countCall) {
case 0:
templates = toTemplate("url");
break;
case 1:
jobs = toJobs("url");
break;
case 2:
job = ... //select item
res = sendJobs(jobs, "url");
break;
default:
runOnUiThread(new Runnable() {
#Override
public void run() {
btnSincro.setEnabled(true);
txtState.append("\n\nEND");
}
});
}
}
private void nextStep() {
setText(txtState, "\nSync \n" + countCall + "/3");
countCall++;
callFlow();
}
private void setText(final TextView text, final String value) {
runOnUiThread(new Runnable() {
#Override
public void run() {
text.setText(value);
}
});
}
public List<Templates> toTemplate(final String... params) {
final List<Templates> list = new ArrayList<>();
Thread t = new Thread(new Runnable() {
#Override
public void run() {
URL url = null;
BufferedReader reader = null;
HttpURLConnection connection = null;
try {
url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
int responseCode = connection.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
String finalJson = buffer.toString();
JSONObject parentObject = new JSONObject(finalJson);
JSONArray parentArray = parentObject.getJSONArray("data");
for (int i = 0; i < parentArray.length(); i++) {
Templates item = new Gson().fromJson(parentArray.get(i).toString(), Templates.class);
list.add(item);
}
} else {
response = connection.getResponseMessage();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null)
connection.disconnect();
try {
if (reader != null)
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
nextStep(); //call next Thread
}
}
});
t.start();
return list;
}
public List<Jobs> toJobs(final String... params) {
final List<Jobs> list = new ArrayList<>();
Thread t = new Thread(new Runnable() {
#Override
public void run() {
URL url = null;
BufferedReader reader = null;
HttpURLConnection connection = null;
try {
url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
int responseCode = connection.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
String finalJson = buffer.toString();
JSONObject parentObject = new JSONObject(finalJson);
JSONArray parentArray = parentObject.getJSONArray("data");
for (int i = 0; i < parentArray.length(); i++) {
Jobs item = new Gson().fromJson(parentArray.get(i).toString(), Jobs.class);
list.add(item);
}
} else {
response = connection.getResponseMessage();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null)
connection.disconnect();
try {
if (reader != null)
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
nextStep();
}
}
});
t.start();
return list;
}
public Boolean sendJobs(final List<Jobs> job, final String... params) {
final Boolean[] result = {false};
Thread t = new Thread(new Runnable() {
#Override
public void run() {
URL url = null;
HttpURLConnection conn = null;
try {
url = new URL(params[0]);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json");
conn.setDoInput(true);
conn.setDoOutput(true);
String str = new Gson().toJson(job);
Log.d(TAG, str);
byte[] outputInBytes = str.getBytes();
OutputStream os = conn.getOutputStream();
os.write(outputInBytes);
os.flush();
int responseCode = conn.getResponseCode();
String response = null;
if (responseCode == HttpsURLConnection.HTTP_OK) {
String line;
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line = br.readLine()) != null) {
response += line;
}
result[0] = true;
} else {
response = conn.getResponseMessage();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
conn.disconnect();
nextStep();
}
}
});
t.start();
return result[0];
}
}
Whenever a thread ends, it calls the nextStep() method, which starts the next trhead.
I am a newbie in android and I've been working around pagination with recyclercview. I am receiving my data from a server(running php) and returning it in a JSON format which brings the data in bunches like 1-10, 11-20... so on. I call notifyDataSetChanged with this. But the problem is recyclerview scrolls back to the top when retrieving more data instead of retaining the current position. How do I go about this?
When scrollbar gets to the bottom, it triggers the asynctask
AsynTask:
public class LoadRecharge extends AsyncTask<String, String, String> {
private boolean socketTimeout = false;
Context context;
public static final String TAG = "custom_message";
public AsyncResponse delegate = null;
private String server_url = "https://blockgator.com/mobile/endless.php";
public LoadRecharge(Context ctxt, AsyncResponse asyncResponse) {
delegate = asyncResponse;
context = ctxt;
}
#Override
protected String doInBackground(String... params) {
if (connectGoogle()) {
String post_data = "";
try {
URL url = new URL(server_url);
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setDoOutput(true);
httpURLConnection.setDoInput(true);
OutputStream outputStream = httpURLConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
post_data = URLEncoder.encode("page", "UTF-8") + "=" + URLEncoder.encode(params[0], "UTF-8");
bufferedWriter.write(post_data);
bufferedWriter.flush();
outputStream.close();
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"));
String result = "";
String line = "";
while ((line = bufferedReader.readLine()) != null) {
result += line;
}
bufferedReader.close();
inputStream.close();
httpURLConnection.disconnect();
return result;
} catch (IOException e) {
Log.e(TAG, "error: " + e.getMessage());
}
} else {
this.socketTimeout = true;
}
return null;
}
#Override
protected void onPreExecute() {
arr.add(null);
scrollAdapter.notifyItemInserted(arr.size() - 1);
}
#Override
protected void onPostExecute(String result) {
arr.remove(arr.size() - 1);
scrollAdapter.notifyItemRemoved(arr.size());
if (this.socketTimeout) {
Toast.makeText(context, "unable to connect to server", Toast.LENGTH_SHORT).show();
} else {
delegate.processFinish(result);
}
}
public boolean connectGoogle() {
try {
HttpURLConnection urlc = (HttpURLConnection) (new URL("http://www.google.com").openConnection());
urlc.setConnectTimeout(3000);
urlc.connect();
return (urlc.getResponseCode() == 200);
} catch (IOException e) {
e.printStackTrace();
return false;
}
}
}
#Override
public void processFinish(String output) {
try {
JSONObject jsonObject = new JSONObject(output);
if (jsonObject.get("status").toString().equals("success")) {
JSONArray jsonarr = jsonObject.getJSONArray("data");
String columns[] = {"id", "bill_amount", "bill_price", "variation"};
for (int i = 0; i < jsonarr.length(); i++) {
ArrayList<String> temp = new ArrayList<>();
for (String column : columns) {
temp.add(jsonarr.getJSONObject(i).getString(column));
}
arr.add(temp);
setAdapter(arr);
}
} else if (jsonObject.get("status").toString().equals("end")) {
total = "end";
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(this, "exception from json", Toast.LENGTH_LONG).show();
} catch (NullPointerException e) {
Toast.makeText(this, "Unable to connect to server...", Toast.LENGTH_LONG).show();
Toast.makeText(this, "Null from json", Toast.LENGTH_LONG).show();
}
}
public void setAdapter(ArrayList<ArrayList<String>> arr) {
recycler.setAdapter(scrollAdapter);
scrollAdapter.notifyDataSetChanged();
scrollAdapter.setLoading();
scrollAdapter.setOnItemClickListener(this);
scrollAdapter.setOnLoadMoreListener(this);
}
Remove this line recycler.setAdapter(scrollAdapter); You need to set your adapter just once either in Activity's onCreate method or Fragment's onCreateView method.
In setAdapter() you dont need to do recycler.setAdapter(scrollAdapter); again, just do it at the beginning
I do something similar, but reversed, working as chat
messages.addAll(0, oldMessages);
mAdapter.notifyItemRangeInserted(0, oldMessages.size());
mAdapter.notifyItemChanged(oldMessages.size());
mAdapter.setLoaded();
Im adding the old messages of the char to the messages.
Then notifing the adapter I have updated the source
I uses the 0 to put at the beginning
I was creating android project in that i am using itemlist view and pagination . while clicking on that particular item i want to get that item id.but i am not getting the unique id.
When i use position then each and every page it is getting form 0-9.
i have the field 'audit_id'. i want to assign this values as item id and i want to get . whether it is possible?
My Code is :
private class AsyncLogin extends AsyncTask<String, String, StringBuilder> {
ProgressDialog pdLoading = new ProgressDialog(Tblview.this);
HttpURLConnection conn;
URL url = null;
#Override
protected void onPreExecute() {
super.onPreExecute();
//this method will be running on UI thread
pdLoading.setMessage("\tLoading...");
pdLoading.setCancelable(false);
pdLoading.show();
}
#Override
protected StringBuilder doInBackground(String... params) {
try {
// Enter URL address where your php file resides
url = new URL("http://192.168.1.99/ashwad/ims/webservices/alldata.php");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
Toast.makeText(getApplicationContext(), "URL Exception", Toast.LENGTH_LONG).show();
e.printStackTrace();
return null;
}
try {
// Setup HttpURLConnection class to send and receive data from php and mysql
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("POST");
// setDoInput and setDoOutput method depict handling of both send and receive
conn.setDoInput(true);
conn.setDoOutput(true);
// Append parameters to URL
Uri.Builder builder = new Uri.Builder()
.appendQueryParameter("user_id", "sdfa")
.appendQueryParameter("password", "asffs");
String query = builder.build().getEncodedQuery();
// Open connection for sending data
OutputStream os = conn.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
writer.write(query);
writer.flush();
writer.close();
os.close();
conn.connect();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return null;
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made
if (response_code == HttpURLConnection.HTTP_OK) {
// Read data sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
result = new StringBuilder();
String next1;
while ((next1 = bufferedReader.readLine()) != null) {
result.append(next1 + "\n");
}
Log.e("dfasf",result.toString());
}
} catch (IOException e) {
e.printStackTrace();
} finally {
conn.disconnect();
}
return result;
}
#Override
protected void onPostExecute(StringBuilder s) {
super.onPostExecute(s);
try {
JSONArray login;
JSONObject obj = new JSONObject(s.toString());
if(s.toString().contains("Result")) {
data = new ArrayList<String>();
login = obj.getJSONArray("Result");
for(int i=0;i<login.length();i++) {
JSONObject c = login.getJSONObject(i);
productsArray = c.getJSONArray(Latest_Products);
TOTAL_LIST_ITEMS=productsArray.length();
int val = TOTAL_LIST_ITEMS%NUM_ITEMS_PAGE;
val = val==0?0:1;
pageCount = (TOTAL_LIST_ITEMS/NUM_ITEMS_PAGE)+val;
for (int j = 0; j < productsArray.length(); j++) {
JSONObject cc = productsArray.getJSONObject(j);
//------------------------------------------------------------------------
Log.e("audit",cc.getString("phone_name"));
String audit_id_str = cc.getString("audit_id");
int audit_id =Integer.parseInt(audit_id_str);
listview.setSelection(audit_id);
data.add(cc.getString("phone_name") +"\n\n"+cc.getString("audit_status") );
loadList(0);
btn_next.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
increment++;
loadList(increment);
CheckEnable();
}
});
btn_prev.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
increment--;
loadList(increment);
CheckEnable();
}
});
//------------------------------------------------------------------------
}
}
pdLoading.dismiss();
//CheckEnable();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
private void loadList(int number)
{
ArrayList<String> sort = new ArrayList<String>();
title.setText("Page "+(number+1)+" of "+pageCount);
int start = number * NUM_ITEMS_PAGE;
for(int i=start;i<(start)+NUM_ITEMS_PAGE;i++)
{
if(i<data.size())
{
sort.add(data.get(i));
}
else
{
break;
}
}
sd = new ArrayAdapter<String>(Tblview.this,android.R.layout.simple_list_item_1,sort);
listview.setAdapter(sd);
}
private void CheckEnable()
{
if(increment+1 == pageCount)
{
btn_next.setEnabled(false);
btn_prev.setEnabled(true);
}
else if(increment == 0)
{
btn_prev.setEnabled(false);
btn_next.setEnabled(true);
}
else
{
btn_prev.setEnabled(true);
btn_next.setEnabled(true);
}
}
}
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
int positon1 =position;
String a1 = Integer.toString(positon1);
Toast.makeText(getApplicationContext(),a1,Toast.LENGTH_SHORT).show();
}
});
If you are keeping count of page then you can add page number to item position.
That will give you unique number for each item.
I would like to retrieve the contents of my variable "$content" in my activity.
But I don't know how to use the return value of my doinbackground.
Can you help me ?
thank you in advance
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String restURL = "https://proxyepn-test.epnbn.net/wsapi/epn";
RestOperation test = new RestOperation();
test.execute(restURL);
}
private class RestOperation extends AsyncTask<String, Void, String> {
//final HttpClient httpClient = new DefaultHttpClient();
String content;
String error;
ProgressDialog progressDialog = new ProgressDialog(MainActivity.this);
String data = "";
TextView serverDataReceived = (TextView)findViewById(R.id.serverDataReceived);
TextView showParsedJSON = (TextView) findViewById(R.id.showParsedJSON);
// EditText userinput = (EditText) findViewById(R.id.userinput);
#Override
protected void onPreExecute() {
super.onPreExecute();
progressDialog.setTitle("Please wait ...");
progressDialog.show();
}
#Override
protected String doInBackground(String... params) {
BufferedReader br = null;
URL url;
try {
url = new URL(params[0]);
URLConnection connection = url.openConnection();
connection.setDoOutput(true);
OutputStreamWriter outputStreamWr = new OutputStreamWriter(connection.getOutputStream());
outputStreamWr.write(data);
outputStreamWr.flush();
br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
StringBuilder sb = new StringBuilder();
String line = null;
while((line = br.readLine())!=null) {
sb.append(line);
sb.append(System.getProperty("line.separator"));
}
content = sb.toString();
} catch (MalformedURLException e) {
error = e.getMessage();
e.printStackTrace();
} catch (IOException e) {
error = e.getMessage();
e.printStackTrace();
} finally {
try {
br.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return content;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
progressDialog.dismiss();
if(error!=null) {
serverDataReceived.setText("Error " + error);
} else {
serverDataReceived.setText(content);
String output = "";
JSONObject jsonResponse;
try {
jsonResponse = new JSONObject(content);
JSONArray jsonArray = jsonResponse.names();
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject child = jsonArray.getJSONObject(i);
String name = child.getString("name");
String number = child.getString("number");
String time = child.getString("date_added");
output = "Name = " + name + System.getProperty("line.separator") + number + System.getProperty("line.separator") + time;
output += System.getProperty("line.separator");
Log.i("content",content);
}
showParsedJSON.setVisibility(View.INVISIBLE);
showParsedJSON.setText(output);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
You can directly call to the method which exist in activity, from onPostExecute method of asynctask by passing "content" value.
#Override
protected void onPostExecute(String content) {
Activity.yourMethod(content);
}
If you want to return the value from asynctask you can use
content = test.execute(url).get();
but it is not a good practice of asynctask, because it is working as serial execution. So it is not fulfill the use of asynctask for palatalization.Because get() will block the UI thread.
I'm really bad at googling things I want so I decided to ask here. My question is is it possible to show a progress bar while fetching the data from the database? I'm using the typical code when fetching data(Pass value to php and the php will do the query and pass it again to android)
Edit(I have tried adding proggressdialog but the problem now is the loaded data will appear first before the progress dialog here's my AsyncTask code)
public class getClass extends AsyncTask<String, Void, String> {
public getClass()
{
pDialog = new ProgressDialog(getActivity());
}
URLConnection connection = null;
String command;
Context context;
String ip = new returnIP().getIpAddresss();
String link = "http://" + ip + "/android/getClass.php";//ip address/localhost
public URLConnection getConnection(String link) {
URL url = null;
try//retrieves link from string
{
url = new URL(link);
} catch (MalformedURLException e) {
e.printStackTrace();
}
URLConnection connection = null;
try//opens the url link provided from the "link" variable
{
connection = url.openConnection();
} catch (IOException e) {
e.printStackTrace();
}
connection.setDoOutput(true);
return connection;
}
public String getResult(URLConnection connection, String logs) {
//this is the functions that retrieves what the php file echoes
//everything that php throws, the phone receives
String result = "";
OutputStreamWriter wr = null;
try {
wr = new OutputStreamWriter(connection.getOutputStream());//compiles data to be sent to the receiver
} catch (IOException e) {
e.printStackTrace();
}
try {
wr.write(logs);
} catch (IOException e) {
e.printStackTrace();
}
try {
wr.flush();//clears the cache-esque thingy of the writer
} catch (IOException e) {
e.printStackTrace();
}
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
} catch (IOException e) {
e.printStackTrace();
}
StringBuilder sb = new StringBuilder();
String line = null;
//Read server response
try {
while ((line = reader.readLine()) != null) {
sb.append(line);
}
} catch (IOException e) {
e.printStackTrace();
}
result = sb.toString();
return result;
}
#Override
protected void onPreExecute() {
pDialog.setMessage("Loading...");
pDialog.show();
}
#Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
String result = "";
//Toast.makeText(View_Classes.this, "ako n una", Toast.LENGTH_LONG).show();
try {
//first data sent is sent in command
command = (String) arg0[0];//it's in array, because everything you input here is placed in arrays
//Toast.makeText(View_Classes.this, "andtio n me", Toast.LENGTH_LONG).show();
if (command == "getCourses") {
connection = getConnection(link);
String logs = "";
logs = "&command=" + URLEncoder.encode(command, "UTF-8");
logs += "&username=" + URLEncoder.encode(username, "UTF-8");
result = getResult(connection, logs);
} else if (command == "getSections") {
connection = getConnection(link);
String logs = "";
logs = "&command=" + URLEncoder.encode(command, "UTF-8");
logs += "&username=" + URLEncoder.encode(username, "UTF-8");
logs += "&course=" + URLEncoder.encode(course, "UTF-8");
result = getResult(connection, logs);
}
return result;
} catch (Exception e) {
return result;
}
}
#Override
protected void onPostExecute(String result) {//this is going to be the next function to be done after the doInBackground function
// TODO Auto-generated method stub
if (pDialog.isShowing()) {
pDialog.dismiss();
}
if (result.equalsIgnoreCase(""))//if there's nothing to return, the text "No records" are going to be thrown
{
} else //Array adapter is needed, to be a place holder of values before passing to spinner
{
}
}
}
Have you tried using an AsyncTask?
You can show your progress bar on the preExecute method and then hide it on postExecute. You can do your querying inside the doInBackground method.
In addition to what #torque203 pointed, I would suggest you to check
http://developer.android.com/reference/android/os/AsyncTask.html#onProgressUpdate(Progress...)
this method was created for that purpose, showing progress to the user.
From developers docs:
private class DownloadFilesTask extends AsyncTask<URL, Integer, Long> {
#Override
protected void onPreExecute() {
//show progress bar here
}
protected Long doInBackground(URL... urls) {
//Pass value to PHP here
//get values from your PHP
}
protected void onPostExecute(Long result) {
//Here you are ready with your PHP value. Dismiss progress bar here.
}
}
public void onPreExecute() {
Progress Dialog pDialog = new ProgressDialog(this);
pDialog.setMessage("Loading...");
pDialog.show();
}
public void doInBackground() {
//do your JSON Coding
}
public void onPostExecute() {
Progress Dialog pDialog = new ProgressDialog(this);
pDialog.setMessage("Loading...");
pDialog.show();
}
public URLConnection getConnection(String link) {
URL url = null;
try//retrieves link from string
{
url = new URL(link);
} catch (MalformedURLException e) {
e.printStackTrace();
}
URLConnection connection = null;
try//opens the url link provided from the "link" variable
{
connection = url.openConnection();
} catch (IOException e) {
e.printStackTrace();
}
connection.setDoOutput(true);
return connection;
}
public String getResult(URLConnection connection, String logs) {
//this is the functions that retrieves what the php file echoes
//everything that php throws, the phone receives
String result = "";
OutputStreamWriter wr = null;
try {
wr = new OutputStreamWriter(connection.getOutputStream());//compiles data to be sent to the receiver
} catch (IOException e) {
e.printStackTrace();
}
try {
wr.write(logs);
} catch (IOException e) {
e.printStackTrace();
}
try {
wr.flush();//clears the cache-esque thingy of the writer
} catch (IOException e) {
e.printStackTrace();
}
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
} catch (IOException e) {
e.printStackTrace();
}
StringBuilder sb = new StringBuilder();
String line = null;
//Read server response
try {
while ((line = reader.readLine()) != null) {
sb.append(line);
}
} catch (IOException e) {
e.printStackTrace();
}
result = sb.toString();
return result;
}
public class getClass extends AsyncTask<String, Void, String> {
#Override
protected void onPreExecute() {
pDialog.setMessage("Loading...");
pDialog.show();
URLConnection connection = null;
String command;
Context context;
String ip = new returnIP().getIpAddresss();
String link = "http://" + ip + "/android/getClass.php";//ip address/localhost
}
#Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
String result = "";
//Toast.makeText(View_Classes.this, "ako n una", Toast.LENGTH_LONG).show();
try {
//first data sent is sent in command
command = (String) arg0[0];//it's in array, because everything you input here is placed in arrays
//Toast.makeText(View_Classes.this, "andtio n me", Toast.LENGTH_LONG).show();
if (command == "getCourses") {
connection = getConnection(link);
String logs = "";
logs = "&command=" + URLEncoder.encode(command, "UTF-8");
logs += "&username=" + URLEncoder.encode(username, "UTF-8");
result = getResult(connection, logs);
} else if (command == "getSections") {
connection = getConnection(link);
String logs = "";
logs = "&command=" + URLEncoder.encode(command, "UTF-8");
logs += "&username=" + URLEncoder.encode(username, "UTF-8");
logs += "&course=" + URLEncoder.encode(course, "UTF-8");
result = getResult(connection, logs);
}
return result;
} catch (Exception e) {
return result;
}
}
#Override
protected void onPostExecute(String result) {//this is going to be the next function to be done after the doInBackground function
// TODO Auto-generated method stub
if (pDialog.isShowing()) {
pDialog.dismiss();
}
if (result.equalsIgnoreCase(""))//if there's nothing to return, the text "No records" are going to be thrown
{
} else //Array adapter is needed, to be a place holder of values before passing to spinner
{
}
}
}