Develop Reference

ListView is not visible

I cant set my ListView dynamically after getting json response from backend.
SherlockNavigationDrawer extends ActionBarActivity
Activity -
public class Forum extends SherlockNavigationDrawer implements OnClickListener {
AsyncTask<Void, String, Void> forumTask;
ProgressDialog pDialog;
TextView newPost;
Button first, last, next, prev;
ListView list;
LinearLayout nopost;
MyPostListAdapter adapter;
public static final String MyPREFERENCES = "MyPrefs";
SharedPreferences sharedpreferences;
String get = "";
JSONObject json;
JSONParser jp;
JSONArray id, user_id, user_name, date, file_path, description, title,
hut_name, hut_id, ttl_likes, ttl_comment;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.forum);
setTitle("Space Huts | Forum");
// newPost = (TextView) findViewById(R.id.tv_test);
first = (Button) findViewById(R.id.bt_first);
prev = (Button) findViewById(R.id.bt_prev);
next = (Button) findViewById(R.id.bt_next);
last = (Button) findViewById(R.id.bt_last);
list = (ListView) findViewById(R.id.lv_posts);
nopost = (LinearLayout) findViewById(R.id.ll_none);
first.setOnClickListener(this);
prev.setOnClickListener(this);
next.setOnClickListener(this);
last.setOnClickListener(this);
// do a get request to server for getting latest 5 pagination posts
doGETrqst("first");
}
private void doGETrqst(final String page) {
// TODO Auto-generated method stub
forumTask = new AsyncTask<Void, String, Void>() {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Forum.this);
pDialog.setMessage("Refreshing " + page + " page.....");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#Override
protected Void doInBackground(Void... arg0) {
sharedpreferences = getSharedPreferences(MyPREFERENCES,
Context.MODE_PRIVATE);
String usrid = sharedpreferences.getString("sesid", "");
// Create URL string
String URL = "http://xxx.xxx?id="
+ usrid + "&page=" + page;
Log.i("json url ", URL);
try {
jp = new JSONParser();
JSONObject json = jp.getJSONFromUrl(URL);
id = json.getJSONArray("id");
user_id = json.getJSONArray("user_id");
user_name = json.getJSONArray("user_name");
date = json.getJSONArray("date");
file_path = json.getJSONArray("file_path");
description = json.getJSONArray("description");
title = json.getJSONArray("title");
hut_name = json.getJSONArray("hut_name");
hut_id = json.getJSONArray("hut_id");
ttl_likes = json.getJSONArray("ttl_likes");
ttl_comment = json.getJSONArray("ttl_comment");
Log.e("recieved" , id.getString(2));
} catch (Exception ex) {
Log.e("error","error");
}
return null;
}
#Override
protected void onPostExecute(Void result) {
forumTask = null;
pDialog.dismiss();
setListView();
}
};
forumTask.execute(null, null, null);
}
private void setListView() {
// TODO Auto-generated method stub
final List<Posts> listposts = new ArrayList<Posts>();
// create list view arraylist for list adapter
for (int i = 0, length = title.length(); i < length - 1; ++i) {
Posts post = new Posts();
try {
post.setHutname(hut_name.getString(i));
post.setPostname(title.getString(i));
post.setUsername(user_name.getString(i));
post.setDate(date.getString(i));
listposts.add(post);
} catch (JSONException e) {
Toast.makeText(this, "Oooppss connectivity error",
Toast.LENGTH_SHORT).show();
}
}
// if there are new posts to show , remove nopost linear layout
if (listposts.size() > 0) {
nopost.setVisibility(View.GONE);
//set the adapter
adapter = new MyPostListAdapter(listposts , Forum.this );
list.setAdapter(adapter);
}
}
#Override
public void onClick(View arg0) {
switch (arg0.getId()) {
case R.id.bt_first:
doGETrqst("first");
break;
case R.id.bt_next:
doGETrqst("next");
break;
case R.id.bt_prev:
doGETrqst("prev");
break;
case R.id.bt_last:
doGETrqst("last");
break;
}
}
}
I want to fill my list view dynamically by getting json response from backend , when user press buttons to get next or previous posts.
However there are no errors in logcat , neither the list view is shown .But this part of setListView() do works ,as my linearlayout implements View.GONE successfully -
if (listposts.size() > 0) {
nopost.setVisibility(View.GONE);
//set the adapter
adapter = new MyPostListAdapter(listposts , Forum.this );
list.setAdapter(adapter);
}
XML LAYOUT forum.xml -
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#000000"
android:orientation="vertical"
android:weightSum="0" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="20"
android:orientation="vertical" >
<TextView
android:id="#+id/tv_newpost"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_gravity="center"
android:background="#drawable/general_buttons"
android:clickable="true"
android:text="New Post"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#drawable/click_text_color"
android:textSize="30dp" />
<LinearLayout
android:id="#+id/ll_none"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="10dp"
android:background="#drawable/shadow"
android:gravity="center"
android:orientation="vertical" >
<TextView
android:id="#+id/tv_none"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:fontFamily="sans-serif-thin"
android:text="No New Post"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#000000" />
<ImageView
android:id="#+id/iv_none"
android:layout_width="150dp"
android:layout_height="match_parent"
android:src="#drawable/none" />
</LinearLayout>
<ScrollView
android:id="#+id/sv_posts"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/lv_posts"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="5dp"
android:visibility="gone" >
</ListView>
</ScrollView>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="horizontal" >
<Button
android:id="#+id/bt_first"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="10dp"
android:background="#drawable/general_buttons"
android:paddingLeft="15dp"
android:paddingRight="20dp"
android:text="FIRST"
android:textColor="#drawable/click_text_color" />
<Button
android:id="#+id/bt_prev"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/general_buttons"
android:paddingLeft="15dp"
android:paddingRight="20dp"
android:text="<<"
android:textColor="#drawable/click_text_color" />
<Button
android:id="#+id/bt_next"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/general_buttons"
android:paddingLeft="20dp"
android:paddingRight="15dp"
android:text=">>"
android:textColor="#drawable/click_text_color" >
</Button>
<Button
android:id="#+id/bt_last"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:background="#drawable/general_buttons"
android:paddingLeft="20dp"
android:paddingRight="15dp"
android:text="LAST"
android:textColor="#drawable/click_text_color" />
</LinearLayout>
</LinearLayout>
After getting responses i updated my code like this -
in onCreate() - before doGETReqst() -
adapter = new MyPostListAdapter(listResults , Forum.this );
list.setAdapter(adapter);
in setListView() -
if (listposts.size() > 0) {
nopost.setVisibility(View.GONE);
//set the adapter
listResults.clear();
listResults.addAll(listposts);
adapter.notifyDataSetChanged();
}
My result is this, now how can i set this into scrollview, in which i nested ListView...i checked my all layouts -
Finally after removing android:view="gone" , adding adapter.notifyDataSetChanged(); and removing scrollview above listview i was able to get this -
Thank you guyz

Your adapter should be created with a List object (for example listResults) and in the setListView do something like:
if (listposts.size() > 0) {
nopost.setVisibility(View.GONE);
//clear old results
listResults.clear();
//load all results
listResults.addAll(listposts);
//notify the adapter about the changes
adapter.notifyDataSetChanged();
}
The point is... create an adapter over an list so... you have ONE instance of that list.
Then update the contents of that list (don't create a new instance), and tell the adapter that the collection has changed.
Try it and let mw know if it works.

In your layout you have android:visibility="gone" set for your listview. I don't see that being toggled in your code.
The answer about updating the adapter instead of creating a new instance is also correct. Initialize your adapter along with your listview and set it (using setAdapter) in the initialization phase. Then when your new data comes in (I modified the code given in the other answer as it was confusing - what's listResults?):
adapter.clear();
//load all results
adapter.addAll(listposts);
//notify the adapter about the changes
adapter.notifyDataSetChanged();

Issue with ListView adapter

When I comment out the code for "nameAdapter = ..." or "numAdapter = ..." and leave the other one uncommented it will display the data in the listview fine. So it is able to display both separately, however, when I leave both uncommented it will only display the data involved with numAdapter. Probably a simple mistake but I can't figure out where I went wrong.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.player);
lv = (ListView) findViewById(R.id.listView);
new Logo().execute();
new statistics().execute();
nameAdapter = new ArrayAdapter<String>(this, R.layout.simple_list_item_1, R.id.stat_name,statName);
numAdapter = new ArrayAdapter<String>(this, R.layout.simple_list_item_1, R.id.stat_number,statNum);
}
private class statistics extends AsyncTask<String, Void, String> {
//final ListView listview = (ListView) findViewById(R.id.listView);
/*String[] values = new String[]{ "Ball Control", "Crossing", "Curve",
"Dribbling", "Finishing", "Free Kick Accuracy", "Heading Accuracy", "Long Passing",
"Long Shots", "Marking", "Penalties", "Short Passing", "Shot Power", "Sliding Tackle",
"Standing Tackle", "Volleys"};*/
//String[] stats = new String[16];
#Override
protected String doInBackground(String... arg) {
Document document;
try {
document = Jsoup.connect(url).get();
num = document.select("div#stats-base p");
statNum.clear();
for (Element element : num) {
statNum.add(element.ownText());
}
name = document.select("div#stats-base span");
statName.clear();
for (Element element : name) {
statName.add(element.ownText());
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
lv.setAdapter(nameAdapter);
lv.setAdapter(numAdapter);
}
}
player.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/playerPic"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/listView"
android:layout_below="#+id/playerPic"
android:layout_centerHorizontal="true"
android:layout_marginTop="104dp"/>
</RelativeLayout>
simple_list_item_1.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView android:id="#+id/stat_name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="10dip"
android:textSize="16dip"
android:textStyle="bold"/>
<TextView
android:id="#+id/stat_number"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="10dip"
android:textSize="16dip"
android:textStyle="bold"
android:layout_below="#id/stat_name"/>
</LinearLayout>

I think there's no mystery in that behavior. The last adapter you set to lv is the one that survives.
If what you're looking for is to add both statName and statNum, I'd set one of them and afterwards use .addAll(...) on the other. For instance:
lv = lv.setAdapter(nameAdapter);
lv.addAll(statNum);
nameAdapter.notifyDataSetChanged();
Don't forget the last line to let your ListView render the new data.

Making changes to layout after setContentView gives blank screen

I have an Activity which is called when a listView item is clicked in a fragment.
My problem is that even after i make changes to my layout(setting text of textviews etc) and calling setContentView, the activity screen is blank.
From the Log.i ive used everywhere, in logcat, i can see all data and it is being properly set, so that isnt the problem.
My question is how do i make it so the changes I've made are displayed on screen/How to refresh the layout with the new data.
public class SemListViewActivity extends Activity
{
JSONObject recdJson=new JSONObject();
JSONArray ar;
ArrayList<HashMap<String, String>> keyslist;
TextView semTCredits, semSession, semGPA;
ListView semList;
SemListAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState)
{
Log.i("Info Tag Sem","Inside Sem");
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
super.onCreate(savedInstanceState);
setContentView(R.layout.sem_details_listview_layout);
//LayoutInflater inflater = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//View v = inflater.inflate(R.layout.sem_details_listview_layout,null);
ar = new JSONArray();
keyslist = new ArrayList<HashMap<String, String>>();
try
{
recdJson = GlobalVars.semJSON;
Log.i("Info Tag Sem","Got the JSON");
ar = recdJson.getJSONArray("seminfo");
Log.i("Info Tag Sem","assigning JSON Array");
for (int i = 0; i < ar.length(); i++)
{
JSONObject jObject = ar.getJSONObject(i);
HashMap<String, String> map = new HashMap<String, String>();
Log.i("Info Tag Sem","jObject Init"+i);
Log.i("Info Tag Sem",jObject.toString());
Log.i("Info Tag Sem",jObject.getString("subcode"));
map.put("subcode", jObject.getString("subcode"));
map.put("sub", jObject.getString("sub"));
map.put("credits", jObject.getString("credits"));
map.put("grade", jObject.getString("grade"));
keyslist.add(map);
}
Log.i("Info Tag Sem","Done with Hashmapping");
semTCredits = (TextView)findViewById(R.id.semTCredits);
semSession = (TextView)findViewById(R.id.semSession);
semGPA = (TextView)findViewById(R.id.semGPA);
Log.i("Info Tag Sem","Set the textviews");
semTCredits.setText("Total Credits: " + recdJson.getString("credits"));
semSession.setText("Session: " + recdJson.getString("session"));
semGPA.setText("Semester GPA: " + recdJson.getString("gpa"));
semList = (ListView)findViewById(R.id.semlist);
adapter = new SemListAdapter(this, keyslist);
semList.setAdapter(adapter);
Log.i("Info Tag Sem","Put the content");
setContentView(R.layout.sem_details_listview_layout);
} catch (JSONException e)
{
e.printStackTrace();
Log.i("Info Tag Sem","Nothing happened ");
}
}
}
and this is the relevant xml layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/semTCredits"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="5dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textStyle="bold" />
<TextView
android:id="#+id/semSession"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="2dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textIsSelectable="true" />
<TextView
android:id="#+id/semGPA"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="2dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textIsSelectable="true" />
<ListView
android:id="#+id/semlist"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
Apologies if this question is duplicate, I have no idea how to word my problem.

You are calling setContentView() twice, this second call:
Log.i("Info Tag Sem","Put the content");
setContentView(R.layout.sem_details_listview_layout);
} catch (JSONException e)
erases all of the changes that you made above... Simply remove it.

How do i add the icons in front of the application to the list

i am trying to list down the applications installed by the user and its icons. so far i managed to get the user installed applications but i am having trouble putting it in the list with the application name and icon together.
Eg row of the list:: {icon} test_application
activity
ArrayList<String> listing = null;
listing = new ArrayList<String>();
ArrayList<Object> icons = new ArrayList<Object>();
CharSequence c = null;
int count = 0;
Drawable icon = null;
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView i = (TextView) findViewById(R.id.textView1);
PackageManager pm = getPackageManager();
List<ApplicationInfo> packages = pm
.getInstalledApplications(PackageManager.GET_META_DATA);
for (ApplicationInfo applicationInfo : packages) {
if ((applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 1) {
count = count + 1;
try {
c = pm.getApplicationLabel(pm.getApplicationInfo(
applicationInfo.processName,
PackageManager.GET_META_DATA));
icon = pm.getApplicationIcon(applicationInfo.packageName);
} catch (NameNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
listing.add(c.toString());
icons.add(icon)
}
}
ListView list = (ListView) findViewById(R.id.listView1);
list.setAdapter(new ArrayAdapter<String>(this, R.layout.text, R.id.textView1, listing));
String Counting = String.valueOf(count);
i.setText(Counting);
}
}
xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
tools:context=".MainActivity" />
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true" >
</ListView>
</RelativeLayout>
row xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
/>
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_toRightOf="#+id/imageView1"
/>
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/imageView1"
android:layout_toRightOf="#+id/textView1"
android:text="TextView" />
</RelativeLayout>

This link has the sample code to create list with text and image.
you need to store the icon also in another data structure (may be one more array list). Then you would have to create your own adapter that create the require view. Check this post out for example code..
Following are the steps you need to follow:
1) Create one class like following:
class MyAppInfo{
public String appName;
public Drawable icon;
}
2) Now change the array list to take this object like following:
ArrayList<MyAppInfo> listing = null;
listing = new ArrayList<MyAppInfo>();
3) Now in your loop create object of MyAppInfo and store the name of the app and icon in that object and add that object to arraylist like following.
PackageManager pm = getPackageManager();
List<ApplicationInfo> packages = pm
.getInstalledApplications(PackageManager.GET_META_DATA);
MyAppInfo tempObj;
for (ApplicationInfo applicationInfo : packages) {
if ((applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 1) {
tempObj = new MyAppInfo();
count = count + 1;
try {
c = pm.getApplicationLabel(pm.getApplicationInfo(
applicationInfo.processName,
PackageManager.GET_META_DATA));
icon = pm.getApplicationIcon(applicationInfo.packageName);
tempObj.appName = c.toString();
tempObj.icon= icon;
} catch (NameNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
listing.add(tempObj);
}
}
4) Now create your own adapter and use this list in get view to create ImageView for icon and TextView for app name...

Radiobutton dynamically

I have a edittext depending on the number given in edit text i have to create a radiobutton but im getting error this is my code
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
// ToDo add your GUI initialization code here
setContentView(R.layout.main);
go=(Button)findViewById(R.id.go);
no=(EditText)findViewById(R.id.noofradio);
err=(TextView)findViewById(R.id.err);
go.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
try
{
int a = Integer.parseInt(no.getText().toString());
RadioGroup radiogroup = new RadioGroup(MainActivity.this);
LinearLayout.LayoutParams rg = new RadioGroup.LayoutParams(
RadioGroup.LayoutParams.WRAP_CONTENT,
RadioGroup.LayoutParams.WRAP_CONTENT);
for (int i = 0; i < a; i++) {
radiobutton = new RadioButton(MainActivity.this);
radiobutton.setText(i);
radiobutton.setId(i);
radiogroup.addView(radiobutton, rg);
}
}
catch(Exception ex)
{
err.setText(ex.toString());
}
}
});
}
}
this is my xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>"
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="RadioButtons"
android:id="#+id/err"/>
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=""
android:id="#+id/noofradio">
</EditText>
<Button
android:id="#+id/go"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Buttons">
</Button>
</LinearLayout>

android content resource$not found exception stringresource id
I think you have an error in your xml (well, using undefined string resource, I guess)

The call to setText() is expecting a string resource id. Specifically, radiobutton.setText(i) is interpreting 'i' to be a string resource id vs. the index you are passing in.