سؤال
In app i am loading data from Url and displaying it in list view.Total Item which I retrieve from Url is 5 Item, Which are displayed successfully in listview.But getView() runs infinite times at backend.IT keeps on calling till activity is alive .I am unable to figure it why it is calling so much time. My code is
https://stackoverflow.com/questions/17130366
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Russianpublic class asasa extends Activity {
//ListView listView;
Intent intent;
public int currentimageindex=0;
private ProgressDialog pDialog;
//Class Declartion DataHolder
DataHolder obj;
Timer timer;
TimerTask task;
ImageView slidingimage;
private int[] IMAGE_IDS = {
R.drawable.myno, R.drawable.cock, R.drawable.item,
R.drawable.ketchup,R.drawable.oil,R.drawable.pan
};
//ProgressDialog progressDialog;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
static final String URL = "http://10.0.2.2/android_connect/get_all_products.php";
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "products";
private static final String TAG_NAME = "name";
private static final String TAG_Description = "description";
private static final String TAG_URL = "url";
private static final String TAG_Price = "price";
LazyAdapter adapter;
// flag for Internet connection status
Boolean isInternetPresent = false;
// products JSONArray
JSONArray products = null;
// Connection detector class
ConnectionDetector cd;
String ITEMTITLE ="HasMapValue";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cd = new ConnectionDetector(getApplicationContext());
// get Internet status
isInternetPresent = cd.isConnectingToInternet();
if (isInternetPresent) {
LoadAllProducts il = new LoadAllProducts();
il.execute(URL);
}
else
{
// Internet connection is not present
// Ask user to connect to Internet
Toast.makeText(asasa.this, "No Internet Connection You don't have internet connection.", Toast.LENGTH_LONG).show();
}
}
public void longToast(CharSequence message) {
Toast.makeText(this, message, Toast.LENGTH_LONG).show();
}
public class LazyAdapter extends BaseAdapter {
private Activity activity;
private LayoutInflater inflater=null;
private ArrayList<HashMap<String, Object>> data;
int i=0;
public LazyAdapter(Activity a, ArrayList<HashMap<String, Object>> d) {
activity = a;
data=d;
inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
public int getCount() {
return data.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
if(convertView==null)
vi = inflater.inflate(R.layout.list_row, null);
TextView title = (TextView)vi.findViewById(R.id.title); // title
TextView artist = (TextView)vi.findViewById(R.id.artist); // artist name
TextView duration = (TextView)vi.findViewById(R.id.duration); // duration
ImageView imageview=(ImageView) vi.findViewById(R.id.list_image);
HashMap<String, Object> song = new HashMap<String, Object>();
song = data.get(position);
DataHolder objj=new DataHolder();
objj=(DataHolder) song.get(ITEMTITLE);
Log.i("iiiiii "," " +i++);
Log.i("objj.GetName() ",objj.GetName());
Log.i("objj.GetDescription() ",objj.GetDescription());
Log.i("objj.GetPrice() ",objj.GetPrice());
title.setText(objj.GetName());
artist.setText(objj.GetDescription());
duration.setText(objj.GetPrice());
imageview.setImageBitmap(objj.Getimage());
return vi;
}
}
class LoadAllProducts extends AsyncTask<String, String, String> {
// creating new HashMap
ArrayList<HashMap<String, Object>> productsList=new ArrayList<HashMap<String,Object>>();
Bitmap decodedByte;
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(asasa.this);
pDialog.setMessage("Loading products. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(URL, "GET", params);
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
products = json.getJSONArray(TAG_PRODUCTS);
Log.i("products ",products.toString());
// looping through All Products
Log.i("LENGTHHHH "," "+products.length());
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
Log.i("ccccccccc ",c.toString());
// Storing each json item in variable
// String id = c.getString(TAG_PID);
String name = c.getString(TAG_NAME);
Log.i("name::",name);
String description = c.getString(TAG_Description);
Log.i("description::",description);
String price = c.getString(TAG_Price);
Log.i("price",price);
byte[] decodedString = Base64.decode(c.getString(TAG_URL), Base64.DEFAULT);
decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
obj=new DataHolder();
obj.setData(name, description, price, decodedByte);
HashMap<String, Object> map = new HashMap<String, Object>();
map.put(ITEMTITLE, obj);
productsList.add(map);
}
} else {
// no products found
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
ListView list;
// dismiss the dialog after getting all products
list=(ListView)findViewById(R.id.list);
adapter=new LazyAdapter(asasa.this, productsList);
list.setAdapter(adapter);
// Click event for single list row
list.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
}
});
if (pDialog.isShowing()) {
pDialog.dismiss();
}
}
}
public void onPause()
{
super.onPause();
}
public class DataHolder
{
String Name;
String Description;
String Price;
Bitmap image;
public void setData(String Name,String Descipton,String Price,Bitmap iamage)
{
this.Name=Name;
this.Description=Descipton;
this.Price=Price;
this.image=iamage;
}
public String GetName()
{return Name;}
public String GetDescription()
{return Description;}
public String GetPrice()
{return Price;}
public Bitmap Getimage()
{return image;}
}
}
And getview()
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
if(convertView==null)
vi = inflater.inflate(R.layout.list_row, null);
TextView title = (TextView)vi.findViewById(R.id.title); // title
TextView artist = (TextView)vi.findViewById(R.id.artist); // artist name
TextView duration = (TextView)vi.findViewById(R.id.duration); // duration
ImageView imageview=(ImageView) vi.findViewById(R.id.list_image);
HashMap<String, Object> song = new HashMap<String, Object>();
song = data.get(position);
DataHolder objj=new DataHolder();
objj=(DataHolder) song.get(ITEMTITLE);
Log.i("iiiiii "," " +i++);
Log.i("objj.GetName() ",objj.GetName());
Log.i("objj.GetDescription() ",objj.GetDescription());
Log.i("objj.GetPrice() ",objj.GetPrice());
title.setText(objj.GetName());
artist.setText(objj.GetDescription());
duration.setText(objj.GetPrice());
imageview.setImageBitmap(objj.Getimage());
return vi;
}
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"
android:background="@drawable/background" >
<include layout="@layout/footer" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="460dp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:background="@drawable/background2"
android:minHeight="400dp"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="50dp"
android:background="@drawable/bar" >
<Button
android:id="@+id/back"
android:layout_width="50dp"
android:layout_height="50dp"
android:background="@drawable/left" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<ImageView
android:id="@+id/ImageView3_Left"
android:layout_width="200dp"
android:layout_height="150dp"
android:layout_gravity="center_vertical|center_horizontal"
android:layout_marginTop="20dp" >
</ImageView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="10dp"
android:background="@drawable/textarea"
android:orientation="vertical" >
<ListView
android:id="@+id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:divider="#b5b5b5"
android:dividerHeight="1dp"
android:listSelector="@drawable/list_selector" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
المحلول
I will post the answer here for others..
When working with ListView, make sure you set a fixed height to the ListView, otherwise getView() will be called multiple times. This is because the ListView tries to calculate how many items can be visible..
نصائح أخرى
and I believe I have solved the problem.
the BaseAdapter adapter requires that the listview has a high associated set to fill_parent or match_parent
