Can't properly change my LinearLayout to ListView
Here is ,my code for selecting images and texts from mysql database through php.And it is displaying in a linearlayout in a scrollview.All i want to do is change my layout to listview like this example. I tried listview and other many ways but its not working properly.I'm new in android,so im trying for a long time.Please help me by editing my code for my requirement.Please.
JAVA
@SuppressLint("NewApi")
public class News_and_events extends Fragment {
private String jsonResult;
private String url = "http://192.168.2.7/crescentnews/select.php";
HttpPost httppost;
StringBuffer buffer;
HttpResponse response;
HttpClient httpclient;
List<NameValuePair> nameValuePairs;
ProgressDialog dialog = null;
ImageView img;
Bitmap bitmap;
ProgressDialog pDialog;
// alert dialog manager
AlertDialogManager alert = new AlertDialogManager();
// Internet detector
ConnectionDetector cd;
InputStream is=null;
String result=null;
String line=null;
int code;
public News_and_events(){}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
pDialog = new ProgressDialog(getActivity());
View rootView = inflater.inflate(R.layout.activity_news_and_events, container, false);
cd = new ConnectionDetector(rootView.getContext());
// Check if Internet present
if (!cd.isConnectingToInternet()) {
// Internet Connection is not present
alert.showAlertDialog(getActivity(),
"Internet Connection Error",
"Please connect to working Internet connection", false);
// stop executing code by return
//return.rootView;
return rootView;
}
accessWebService();
return rootView;
}
// Async Task to access the web
private class JsonReadTask extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(1);
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(params[0]);
try {
httppost.setEntity(new UrlEncodedFormEntity(nameValuePair));
HttpResponse response = httpclient.execute(httppost);
jsonResult = inputStreamToString(
response.getEntity().getContent()).toString();
}
catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
private StringBuilder inputStreamToString(InputStream is) {
String rLine = "";
StringBuilder answer = new StringBuilder();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
try {
while ((rLine = rd.readLine()) != null) {
answer.append(rLine);
}
}
catch (IOException e) {
// e.printStackTrace();
Toast.makeText(getActivity().getApplicationContext(),
"Error..." + e.toString(), Toast.LENGTH_LONG).show();
}
return answer;
}
@Override
protected void onPostExecute(String result) {
display();
}
}// end async task
public void accessWebService() {
JsonReadTask task = new JsonReadTask();
// passes values for the urls string array
task.execute(new String[] { url });
}
// build hash set for list view
public void display() {
try {
JSONObject jsonResponse = new JSONObject(jsonResult);
JSONArray jsonMainNode = jsonResponse.optJSONArray("news_details");
LinearLayout MainLL= (LinearLayout)getActivity().findViewById(R.id.newslayout);
//LinearLayout headLN=(LinearLayout)findViewById(R.id.headsection);
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
final String head = jsonChildNode.optString("title");
final String details = jsonChildNode.optString("text");
final String date = jsonChildNode.optString("date");
final String image = jsonChildNode.optString("img");
//final String time = jsonChildNode.optString("time");
//img = new ImageView(this.getActivity());
//new LoadImage().execute("http://192.168.2.7/crescentnews/images/"+image);
img = new ImageView(this.getActivity());
// Toast.makeText(getActivity(),image, Toast.LENGTH_LONG).show();
LoadImage ldimg=new LoadImage();
ldimg.setImage(img);
ldimg.execute("http://192.168.2.7/crescentnews/images/"+image);
TextView headln = new TextView(this.getActivity());
headln.setText(head); // News Headlines
headln.setTextSize(16);
headln.setTextColor(Color.BLACK);
headln.setGravity(Gravity.CENTER);
headln.setBackgroundColor(Color.parseColor("#ffcd14"));
// headln.setBackgroundResource(R.drawable.menubg);
headln.setPadding(0, 20, 0, 0);
// headln.setHeight(50);
headln.setClickable(true);
TextView dateln = new TextView(this.getActivity());
dateln.setText(date); // News Headlines
dateln.setTextSize(12);
dateln.setTextColor(Color.BLACK);
dateln.setGravity(Gravity.RIGHT);
//dateln.setBackgroundColor(Color.parseColor("#f20056"));
dateln.setBackgroundColor(0x00000000);
dateln.setPadding(0, 0, 10, 10);
dateln.setWidth(100);
dateln.setClickable(true);
View sep=new View(this.getActivity());
sep.setBackgroundColor(Color.parseColor("#252525"));
sep.setMinimumHeight(10);
TextView detailsln = new TextView(this.getActivity());
detailsln.setText(details); // News Details
detailsln.setTextSize(12);
detailsln.setTextColor(Color.BLACK);
detailsln.setGravity(Gravity.CENTER);
detailsln.setPadding(10, 10, 10, 10);
int width = LayoutParams.WRAP_CONTENT;
int height = 200;
LinearLayout.LayoutParams parms = new LinearLayout.LayoutParams(width,height);
img.setLayoutParams(parms);
parms.gravity = Gravity.CENTER;
img.setPaddingRelative (15, 15, 15, 15);
MainLL.addView(headln);
MainLL.addView(dateln);
// MainLL.addView(photo);
MainLL.addView(img);
MainLL.addView(detailsln);
MainLL.addView(sep);
img.setClickable(true);
// img.buildDrawingCache();
// final Bitmap bmap = img.getDrawingCache();
headln.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity().getApplicationContext(),InnerNewsAndEvents.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
intent.putExtra("image", image);
startActivity(intent);
}
});
dateln.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity().getApplicationContext(),InnerNewsAndEvents.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
intent.putExtra("image", image);
startActivity(intent);
}
});
img.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity().getApplicationContext(),InnerNewsAndEvents.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
intent.putExtra("image", image);
startActivity(intent);
}
});
detailsln.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity().getApplicationContext(),InnerNewsAndEvents.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
intent.putExtra("image", image);
startActivity(intent);
}
});
}
} catch (JSONException e) {
Toast.makeText(getActivity().getApplicationContext(), "Error" + e.toString(),
Toast.LENGTH_SHORT).show();
}
}
private class LoadImage extends AsyncTask<String, String, Bitmap> {
ImageView img;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog.setMessage("Loading Image ....");
pDialog.show();
}
public void setImage(ImageView img ){
this.img=img;
}
protected Bitmap doInBackground(String... args) {
try {
bitmap = BitmapFactory.decodeStream((InputStream)new URL(args[0]).openStream());
}
catch (Exception e) { e.printStackTrace(); }
return bitmap;
}
protected void onPostExecute(Bitmap image) {
if(image != null){
img.setImageBitmap(image);
pDialog.dismiss();
}
pDialog.dismiss();
}
}
public static boolean isInternetReachable()
{
try {
//make a URL to a known source
URL url = new URL("http://www.google.com");
//open a connection to that source
HttpURLConnection urlConnect = (HttpURLConnection)url.openConnection();
//trying to retrieve data from the source. If there
//is no connection, this line will fail
Object objData = urlConnect.getContent();
} catch (UnknownHostException e) {
e.printStackTrace();
return false;
}
catch (IOException e) {
e.printStackTrace();
return false;
}
return true;
}
}
XML
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="match_parent"[![enter image description here][1]][1]
(source: codelearn.org)
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:baselineAligned="false"
>
<LinearLayout
android:id="@+id/newslayout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:background="#ffffff"
>
</LinearLayout>
</LinearLayout>
</ScrollView>
</LinearLayout>
Ashfaq
Glorfindel
1 Answer
You cannot call display() from within AsyncTask to display results in listview.
You should follow the following steps
Inside on create, Call AsyncTask to fetch the data from server and populate this into an Array List. While async task is running, make sure you display a progress dialogue so that user cannot do anything in the UI thread.
Inside on create, do initialize your listview.
inside on Post execute of AsyncTask, after you have populated all the elements in the arraylist, call the adapter to populate the listview.
Define an adapter which extends BaseAdapter using which you can populate the listview from the array list.
You may want to check out this link for a similar working example.
answered on Stack Overflow Jan 8, 2015 by 
Phillip Dunley
Phillip DunleyUser contributions licensed under CC BY-SA 3.0