The question:
I have an EditText which takes a String from the user and a searchButton.
When the searchButton is clicked, it will search through the XML file and display it in the ListView.
I am able to take input from the user, search through the XML file and display the usersearched value in the ListView also.
What I want is to display a ProgressDialog after the searchButton is clicked like “PLEASE WAIT…RETRIEVING DATA…” or something like that and dismiss it when the data is shown.
public class Tab1Activity extends ListActivity {
private Button okButton;
private Button searchButton;
Toast toast;
String xml;
private TextView searchText;
private String searchTextString;
HashMap<String, String> o;
ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.tab1);
searchButton = (Button) findViewById(R.id.search_button);
searchButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
System.out.print("hello");
searchText = (TextView) findViewById(R.id.search_text);
searchTextString = searchText.getText().toString();
readXml(searchTextString);
}
});
}
private void readXml(String searchTextString1) {
ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();
String xml = XMLfunctions.getXML();
//Here XMLfunctions is class name which parse xml
Document doc = XMLfunctions.XMLfromString(xml);
int numResults = XMLfunctions.numResults(doc);
if ((numResults <= 0)) {
Toast.makeText(Tab1Activity.this, "Testing xmlparser",
Toast.LENGTH_LONG).show();
finish();
}
NodeList nodes = doc.getElementsByTagName("result");
for (int i = 0; i < nodes.getLength(); i++) {
HashMap<String, String> map = new HashMap<String, String>();
Element e = (Element) nodes.item(i);
String nameMapString = XMLfunctions.getValue(e, "name");
if ( nameMapString.toLowerCase().indexOf(searchTextString1.toLowerCase()) != -1 ) // != -1 means string is present in the search string
{
map.put("id", XMLfunctions.getValue(e, "id"));
map.put("name", XMLfunctions.getValue(e, "name"));
map.put("Score", XMLfunctions.getValue(e, "score"));
mylist.add(map);
}
}
ListAdapter adapter = new SimpleAdapter(this, mylist,
R.layout.parsexml, new String[] { "name", "Score" }, new int[] {
R.id.item_title, R.id.item_subtitle });
setListAdapter(adapter);
final ListView lv = getListView();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
@SuppressWarnings("unchecked")
HashMap<String, String> o = (HashMap<String, String>) lv
.getItemAtPosition(position);
Toast.makeText(Tab1Activity.this,
"Name "+o.get("name")+" Clicked", Toast.LENGTH_LONG)
.show();
}
});
}
The Solutions:
Below are the methods you can try. The first solution is probably the best. Try others if the first one doesn’t work. Senior developers aren’t just copying/pasting – they read the methods carefully & apply them wisely to each case.
Method 1
Declare your progress dialog:
ProgressDialog progress;
When you’re ready to start the progress dialog:
progress = ProgressDialog.show(this, "dialog title",
"dialog message", true);
and to make it go away when you’re done:
progress.dismiss();
Here’s a little thread example for you:
// Note: declare ProgressDialog progress as a field in your class.
progress = ProgressDialog.show(this, "dialog title",
"dialog message", true);
new Thread(new Runnable() {
@Override
public void run()
{
// do the thing that takes a long time
runOnUiThread(new Runnable() {
@Override
public void run()
{
progress.dismiss();
}
});
}
}).start();
Method 2
I am using the following code in one of my current projects where i download data from the internet. It is all inside my activity class.
// ---------------------------- START DownloadFileAsync // -----------------------//
class DownloadFileAsync extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// DIALOG_DOWNLOAD_PROGRESS is defined as 0 at start of class
showDialog(DIALOG_DOWNLOAD_PROGRESS);
}
@Override
protected String doInBackground(String... urls) {
try {
String xmlUrl = urls[0];
URL u = new URL(xmlUrl);
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
int lengthOfFile = c.getContentLength();
InputStream in = c.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
long total = 0;
while ((len1 = in.read(buffer)) > 0) {
total += len1; // total = total + len1
publishProgress("" + (int) ((total * 100) / lengthOfFile));
xmlContent += buffer;
}
} catch (Exception e) {
Log.d("Downloader", e.getMessage());
}
return null;
}
protected void onProgressUpdate(String... progress) {
Log.d("ANDRO_ASYNC", progress[0]);
mProgressDialog.setProgress(Integer.parseInt(progress[0]));
}
@Override
protected void onPostExecute(String unused) {
dismissDialog(DIALOG_DOWNLOAD_PROGRESS);
}
}
@Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case DIALOG_DOWNLOAD_PROGRESS:
mProgressDialog = new ProgressDialog(this);
mProgressDialog.setMessage("Retrieving latest announcements...");
mProgressDialog.setIndeterminate(false);
mProgressDialog.setMax(100);
mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
mProgressDialog.setCancelable(true);
mProgressDialog.show();
return mProgressDialog;
default:
return null;
}
}
Method 3
While creating the object for the progressbar check the following.
This fails:
dialog = new ProgressDialog(getApplicationContext());
While adding the activities context works..
dialog = new ProgressDialog(MainActivity.this);
Method 4
You should not execute resource intensive tasks in the main thread. It will make the UI unresponsive and you will get an ANR. It seems like you will be doing resource intensive stuff and want the user to see the ProgressDialog. You can take a look at http://developer.android.com/reference/android/os/AsyncTask.html to do resource intensive tasks. It also shows you how to use a ProgressDialog.
Method 5
I am using the following code in one of my current projects where i download data from the internet. It is all inside my activity class.
private class GetData extends AsyncTask<String, Void, JSONObject> {
@Override
protected void onPreExecute() {
super.onPreExecute();
progressDialog = ProgressDialog.show(Calendar.this,
"", "");
}
@Override
protected JSONObject doInBackground(String... params) {
String response;
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
HttpResponse responce = httpclient.execute(httppost);
HttpEntity httpEntity = responce.getEntity();
response = EntityUtils.toString(httpEntity);
Log.d("response is", response);
return new JSONObject(response);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(JSONObject result)
{
super.onPostExecute(result);
progressDialog.dismiss();
if(result != null)
{
try
{
JSONObject jobj = result.getJSONObject("result");
String status = jobj.getString("status");
if(status.equals("true"))
{
JSONArray array = jobj.getJSONArray("data");
for(int x = 0; x < array.length(); x++)
{
HashMap<String, String> map = new HashMap<String, String>();
map.put("name", array.getJSONObject(x).getString("name"));
map.put("date", array.getJSONObject(x).getString("date"));
map.put("description", array.getJSONObject(x).getString("description"));
list.add(map);
}
CalendarAdapter adapter = new CalendarAdapter(Calendar.this, list);
list_of_calendar.setAdapter(adapter);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
else
{
Toast.makeText(Calendar.this, "Network Problem", Toast.LENGTH_LONG).show();
}
}
}
and execute it in OnCreate Method like new GetData().execute();
where Calendar is my calendarActivity and i have also created a CalendarAdapter to set these values to a list view.
All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0