Develop Reference

Android GridView - notifyDataSetChanged not refreshing the GridView

I am writing an app that displays a grid of images stored on a local database using GridView. I implemented the deleteSelectedImage method triggered by a button which deletes a given image of the grid in the database. The deletion works, but I cannot get my GridView to refresh by itself... If I close the activity and then open it again, the changes are visible.
Here's my code :
The activity :
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.TextView;
public class GalleryShowActivity extends AppCompatActivity {
private final String DEBUG_TAG = "GalleryShowActivity";
private DatabaseHandler db;
private Cursor c;
private ImageAdapter mBaseAdapter;
private TextView selectedImageText;
private GridView mGridView;
// currently selected position in the grid
private int mSelectedPos;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_gallery_show);
db = new DatabaseHandler(this);
c = db.getCursorOnAllImages(this);
mBaseAdapter = new ImageAdapter(this, c, db);
mSelectedPos = -1;
selectedImageText = (TextView) findViewById(R.id.selectedImageText);
selectedImageText.setText("Selected image : NONE");
mGridView = (GridView) findViewById(R.id.gridview);
mGridView.setAdapter(mBaseAdapter);
mGridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
Log.d(DEBUG_TAG, "IMAGE CLICKED");
// click selects an image (can be changed later)
mSelectedPos = position;
selectedImageText.setText("Selected image : " + (position + 1));
}
});
}
public void deleteSelectedImage(View view) {
boolean exists = c.moveToPosition(mSelectedPos);
if (exists) {
boolean success = db.deletePointedPicture(c, this);
if (success) {
Log.d(DEBUG_TAG, "DELETE SUCCESS");
mBaseAdapter.notifyDataSetChanged();
// display a success message...
}
} else {
// display an error...
}
}
}
And here is the code for the ImageAdapter class :
package ch.epfl.sweng.project;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
class ImageAdapter extends BaseAdapter {
private Context mContext;
private Cursor mCursor;
private DatabaseHandler mHandler;
ImageAdapter(Context context, Cursor cursor, DatabaseHandler handler) {
mContext = context;
mCursor = cursor;
mHandler = handler;
}
#Override
public int getCount() {
return mCursor.getCount();
}
#Override
public Object getItem(int position) {
return null;
}
#Override
public long getItemId(int position) {
return 0;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
int rowHeight = 200;
int rowWidth = 300;
ImageView imageView;
if (convertView == null) {
// if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(rowWidth, rowHeight));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
} else {
imageView = (ImageView) convertView;
}
Bitmap bm = mHandler.getImageByIndex(mCursor, position);
imageView.setImageBitmap(bm);
imageView.setVisibility(View.VISIBLE);
return imageView;
}
}
I also tried this :
mBaseAdapter = new ImageAdapter(this, c, db);
mGridView.setAdapter(mBaseAdapter);
Instead of :
mBaseAdapter.notifyDataSetChanged();
But it did not work.

You are implementing it wrong. Even after deletion data in cursor will be same. Data in cursor is only updated when onCreate() is again called. Either update the cursor on deleteSelectedImage method after deleting the data and then call notifyDataSetChanged or try to pass list instead of cursor in constructor and while deleting, delete data from list as well as database and then call notifyDataSetChanged.

How to implement endless scrolling listview

I am creating an application in which I am parsing data using Json parsing. I've implemented listview and in my response i have totalpage and current page objects,
A new user will get items from the first page. While the user is scrolling through the listview, the list expands with items from the next page (and the next and the next etc.)
this is my response
http://pastie.org/10259792
The following is code I've tried:
HomeFragment
public class HomeFragment extends Fragment {
// Listview Adapter
ListViewAdapter adapters;
// Connection detector
ConnectionDetector cd;
// Alert dialog manager
AlertDialogManager alert = new AlertDialogManager();
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONparserr jsonParser = new JSONparserr();
ArrayList<HashMap<String, String>> WebsiteList;
// albums JSONArray
JSONArray data = null;
String link_url;
ArrayList<HashMap<String, String>> arrayTemplist;
private AutoCompleteTextView inputSearch;
private ListView lv;
private static final String URL_ALBUMS = "";
private static final String WEBSITE_MENU_ID ="Brand_name";
private static final String TAG_MATCH="data";
//private static final String TAG_NAME="Brand_name";
private static final String TAG_PROFILE="id";
private static final String TAG_CAST="Company";
public HomeFragment(){}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_home, container, false);
lv = (ListView)rootView.findViewById(R.id.listpehlu);
cd = new ConnectionDetector(getActivity());
WebsiteList = new ArrayList<HashMap<String, String>>();
// Loading Albums JSON in Background Thread
new LoadAlbums().execute();
// get listview
inputSearch = (AutoCompleteTextView)rootView.findViewById(R.id.autoCompleteTextViewhomefrag);
inputSearch.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
arrayTemplist= new ArrayList<HashMap<String,String>>();
String searchString =inputSearch.getText().toString().toLowerCase();
for (int i = 0; i < WebsiteList.size(); i++)
{
String currentString =WebsiteList.get(i).get(HomeFragment.this.WEBSITE_MENU_ID);
if (currentString.toLowerCase().startsWith(searchString ))
{
arrayTemplist.add(WebsiteList.get(i));
}
}
for (int i = 0; i < arrayTemplist.size(); i++)
{
String currentstrin = arrayTemplist.get(i).get(HomeFragment.this.WEBSITE_MENU_ID);
//Toast.makeText(getApplicationContext(), currentstrin, Toast.LENGTH_LONG).show();
}
SimpleAdapter adapters = new SimpleAdapter(getActivity(), arrayTemplist,R.layout.list_item_match, new String[] {WEBSITE_MENU_ID,TAG_CAST
}, new int[] {
R.id.txtbrndnm,R.id.txtbrndcomp});
lv.setAdapter(adapters);
}
#Override
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
int arg3) {
// TODO Auto-generated method stub
}
#Override
public void afterTextChanged(Editable arg0) {
// TODO Auto-generated method stub
}
});
lv.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View view, int position,
long arg3) {
Selected_Product_Listing tf = new Selected_Product_Listing();
Bundle bundle = new Bundle();
bundle.putString("prducts_name", WebsiteList.get(position).get((WEBSITE_MENU_ID)));
// bundle.putString("prducts_name", aList.get(position).get(INTEREST_ACCEPT_NAME));
tf.setArguments(bundle);
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(R.id.frame_container, tf);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
ft.addToBackStack(null);
ft.commit();
// Toast.makeText(getActivity(),"lets"+ WebsiteList.get(position).get(convertToBase64(convertToBase64(WEBSITE_MENU_ID))), Toast.LENGTH_LONG).show();
}
});
lv.setOnScrollListener(new OnScrollListener() {
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
if(firstVisibleItem+visibleItemCount == totalItemCount && totalItemCount!=0)
{
}
}
});
return rootView;
}
public String convertToBase64(String text) {
byte[] data = null;
try {
data = text.getBytes("UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return Base64.encodeToString(data, Base64.DEFAULT);
}
class LoadAlbums extends AsyncTask<String, String, String> {
private JSONObject jsonObj;
/**
* Before starting background thread Show Progress Dialog
* */
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading...");
pDialog.setIndeterminate(true);
pDialog.setIndeterminateDrawable(getResources().getDrawable(R.drawable.custom_progress));
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
String json = jsonParser.makeHttpRequest(URL_ALBUMS, "GET",
params);
// Check your log cat for JSON reponse
Log.d("Albums JSON: ", "> " + json);
if (json != null) {
try {
jsonObj = new JSONObject(json);
// Getting JSON Array node
data = jsonObj.getJSONArray(TAG_MATCH);
String totpage=jsonObj.getString("total_page");
System.out.println("Total Page"+totpage);
String curpage=jsonObj.getString("current_page");
System.out.println("Total Page"+curpage);
// looping through All Contacts
for (int i = 0; i < data.length(); i++) {
JSONObject c = data.getJSONObject(i);
HashMap<String, String> map = new HashMap<String, String>();
map.put(WEBSITE_MENU_ID,c.getString(WEBSITE_MENU_ID));
map.put(TAG_PROFILE, c.getString(TAG_PROFILE));
map.put(TAG_CAST, c.getString(TAG_CAST));
WebsiteList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all albums
pDialog.dismiss();
// updating UI from Background Thread
ListAdapter adapter = new SimpleAdapter(
getActivity(), WebsiteList,
R.layout.list_item_match, new String[] {WEBSITE_MENU_ID,TAG_CAST
}, new int[] {
R.id.txtbrndnm,R.id.txtbrndcomp});
lv.setAdapter(adapter);
}
}
EndlessAdapter
public class EndLessAdapter extends ArrayAdapter<String> {
private Context context;
private List<String> items;
private int layoutId;
public EndLessAdapter(Context context, List<String> items, int LayoutId) {
super(context,LayoutId,items);
this.context = context;
this.items = items;
this.layoutId = LayoutId;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if(convertView == null)
convertView = ((LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(layoutId,parent,false);
TextView tView = (TextView)convertView.findViewById(R.id.txt);
tView.setText(items.get(position));
return convertView;
}
}
EndlessLisView
public class EndlessListView extends ListView implements OnScrollListener {
private Context context;
private View footer;
private boolean isLoading;
private EndLessListener listener;
private BaseAdapter adapter;
public EndlessListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
this.setOnScrollListener(this);
this.context = context;
}
public EndlessListView(Context context, AttributeSet attrs) {
super(context, attrs);
this.setOnScrollListener(this);
this.context = context;
}
public EndlessListView(Context context) {
super(context);
this.setOnScrollListener(this);
this.context = context;
}
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
// 4
public void addNewData() {
this.removeFooterView(footer);
// adapter.addAll(products);
adapter.notifyDataSetChanged();
isLoading = false;
}
public void setLoading()
{
isLoading = false;
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount) {
if(getAdapter() == null)
return;
if(getAdapter().getCount() == 0)
return;
int l = visibleItemCount + firstVisibleItem;
System.out.println("List View Total Item Count = "+totalItemCount+" , l = "+l+", is_loading = "+isLoading);
if(l >= totalItemCount && !isLoading){
// add footer layout
this.addFooterView(footer);
// set progress boolean
isLoading = true;
System.out.println("$$$$$$$$$ call loaddata $$$$$$$$$$$");
// call interface method to load new data
listener.loadData();
}
}
// Calling order from MainActivity
// 1
public void setLoadingView(int resId) {
footer = ((LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(resId, null); // footer = (View)inflater.inflate(resId, null);
this.addFooterView(footer);
System.out.println("addfooter ====######");
}
// 2
public void setListener(EndLessListener listener) {
this.listener = listener;
}
// 3
public void setAdapter(BaseAdapter adapter) {
super.setAdapter(adapter);
this.adapter = adapter;
this.removeFooterView(footer);
}
public void removeFooter(){
this.removeFooterView(footer);
}
}

You can achieve this by using the following library in Github
https://github.com/nicolasjafelle/PagingListView
Simple create your PagingAdapter and add it to com.paging.listview.PagingListView.
You have to implements the new Pagingable interface and its onLoadMoreItems() method. For example:
listView.setHasMoreItems(true);
listView.setPagingableListener(new PagingListView.Pagingable() {
#Override
public void onLoadMoreItems() {
if (pager < 3) {
new CountryAsyncTask(false).execute();
} else {
listView.onFinishLoading(false, null);
}
}
});
Finally you can use the onFinishLoading(boolean hasMoreItems, List newItems) method to update the list.
listView.onFinishLoading(true, newItems);
Also remember to use this package in your layout files:
<com.paging.listview.PagingListView
android:id="#+id/paging_list_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

Hello here you can find the nostra library for lazy loading and then you can
implement the following example for lazzy loading
https://github.com/nostra13/Android-Universal-Image-Loader
you can achieve Lazy loading by using the below
code
Lets start the coding about the lazy loading.
MainActivity.java
package com.sunil.lazyloading;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity implements OnClickListener{
private Button btnlist=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnlist= (Button)findViewById(R.id.button_listview);
btnlist.setOnClickListener(this);
}
#Override
public void onClick(View arg0) {
Intent intent = new Intent(this, ImageListActivity.class);
intent.putExtra("stringarrayimage", Constants.IMAGES);
startActivity(intent);
}
}
CustomAdapter.java
package com.sunil.adapter;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.assist.ImageLoadingListener;
import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;
import com.sunil.lazyloading.R;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class CustomAdapter extends BaseAdapter{
private String imageurl[]=null;
private Context context=null;
DisplayImageOptions doption=null;
private ImageLoadingListener animateFirstListener =null;
public CustomAdapter(Activity activity, String[] imageurl)
{
this.context=activity;
this.imageurl=imageurl;
doption=new DisplayImageOptions.Builder().showImageForEmptyUri(R.drawable.ic_empty).showImageOnFail(R.drawable.ic_error).showStubImage(R.drawable.ic_stub).cacheInMemory(true).cacheOnDisc(true).displayer(new RoundedBitmapDisplayer(20)).build();
animateFirstListener = new AnimateFirstDisplayListener();
}
#Override
public int getCount() {
return imageurl.length;
}
#Override
public Object getItem(int arg0) {
return arg0;
}
#Override
public long getItemId(int arg0) {
return arg0;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView;
final ViewHolder holder;
if (convertView == null) {
view = ((Activity) context).getLayoutInflater().inflate(R.layout.item_list_row, parent, false);
holder = new ViewHolder();
holder.text = (TextView) view.findViewById(R.id.text);
holder.image = (ImageView) view.findViewById(R.id.image);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
holder.text.setText("Item " + (position + 1));
ImageLoader imageLoader = ImageLoader.getInstance();
imageLoader.displayImage(imageurl[position], holder.image, doption, animateFirstListener);
return view;
}
private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {
static final List<string> displayedImages = Collections.synchronizedList(new LinkedList<string>());
#Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
if (loadedImage != null) {
ImageView imageView = (ImageView) view;
boolean firstDisplay = !displayedImages.contains(imageUri);
if (firstDisplay) {
FadeInBitmapDisplayer.animate(imageView, 500);
displayedImages.add(imageUri);
}
}
}
}
private class ViewHolder {
public TextView text;
public ImageView image;
}
}
</string></string>
ImageListActivity.java
package com.sunil.lazyloading;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ImageView;
import android.widget.ListView;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;
MainActivity.java
package com.sunil.lazyloading;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity implements OnClickListener{
private Button btnlist=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnlist= (Button)findViewById(R.id.button_listview);
btnlist.setOnClickListener(this);
}
#Override
public void onClick(View arg0) {
Intent intent = new Intent(this, ImageListActivity.class);
intent.putExtra("stringarrayimage", Constants.IMAGES);
startActivity(intent);
}
}
CustomAdapter.java
package com.sunil.adapter;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.assist.ImageLoadingListener;
import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;
import com.sunil.lazyloading.R;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class CustomAdapter extends BaseAdapter{
private String imageurl[]=null;
private Context context=null;
DisplayImageOptions doption=null;
private ImageLoadingListener animateFirstListener =null;
public CustomAdapter(Activity activity, String[] imageurl)
{
this.context=activity;
this.imageurl=imageurl;
doption=new DisplayImageOptions.Builder().showImageForEmptyUri(R.drawable.ic_empty).showImageOnFail(R.drawable.ic_error).showStubImage(R.drawable.ic_stub).cacheInMemory(true).cacheOnDisc(true).displayer(new RoundedBitmapDisplayer(20)).build();
animateFirstListener = new AnimateFirstDisplayListener();
}
#Override
public int getCount() {
return imageurl.length;
}
#Override
public Object getItem(int arg0) {
return arg0;
}
#Override
public long getItemId(int arg0) {
return arg0;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView;
final ViewHolder holder;
if (convertView == null) {
view = ((Activity) context).getLayoutInflater().inflate(R.layout.item_list_row, parent, false);
holder = new ViewHolder();
holder.text = (TextView) view.findViewById(R.id.text);
holder.image = (ImageView) view.findViewById(R.id.image);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
holder.text.setText("Item " + (position + 1));
ImageLoader imageLoader = ImageLoader.getInstance();
imageLoader.displayImage(imageurl[position], holder.image, doption, animateFirstListener);
return view;
}
private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {
static final List<string> displayedImages = Collections.synchronizedList(new LinkedList<string>());
#Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
if (loadedImage != null) {
ImageView imageView = (ImageView) view;
boolean firstDisplay = !displayedImages.contains(imageUri);
if (firstDisplay) {
FadeInBitmapDisplayer.animate(imageView, 500);
displayedImages.add(imageUri);
}
}
}
}
private class ViewHolder {
public TextView text;
public ImageView image;
}
}
</string></string>
ImageListActivity.java
package com.sunil.lazyloading;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ImageView;
import android.widget.ListView;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.sunil.adapter.CustomAdapter;
public class ImageListActivity extends Activity implements OnItemClickListener{
private ListView listview=null;
private String[] imageUrls;
protected ImageLoader imageLoader=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.imagelist);
listview=(ListView)findViewById(R.id.listView_image);
imageLoader = ImageLoader.getInstance();
Bundle bundle = getIntent().getExtras();
imageUrls = bundle.getStringArray("stringarrayimage");
CustomAdapter adapter=new CustomAdapter(ImageListActivity.this, imageUrls);
listview.setAdapter(adapter);
listview.setOnItemClickListener(this);
}
#Override
public void onItemClick(AdapterView arg0, View arg1, int position, long arg3) {
Intent intent = new Intent(this, ImagePagerActivity.class);
intent.putExtra("imageurlpostion", imageUrls);
intent.putExtra("imagepostion", position);
startActivity(intent);
}
#Override
public void onBackPressed() {
AnimateFirstDisplayListener.displayedImages.clear();
super.onBackPressed();
}
private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {
static final List<string> displayedImages = Collections.synchronizedList(new LinkedList<string>());
#Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
if (loadedImage != null) {
ImageView imageView = (ImageView) view;
boolean firstDisplay = !displayedImages.contains(imageUri);
if (firstDisplay) {
FadeInBitmapDisplayer.animate(imageView, 500);
displayedImages.add(imageUri);
}
}
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.item_clear_memory_cache:
imageLoader.clearMemoryCache();
return true;
case R.id.item_clear_disc_cache:
imageLoader.clearDiscCache();
return true;
default:
return false;
}
}
}
activity_main.xml
<button android:id="#+id/button_listview" android:layout_height="wrap_content" android:layout_width="wrap_content" android:text="ListView ImageLoad">
imagelist.xml
<listview android:id="#+id/listView_image" android:layout_height="match_parent" android:layout_width="match_parent">
</listview>
item_list_row.xml
<imageview android:adjustviewbounds="true" android:contentdescription="#string/descr_image" android:id="#+id/image" android:layout_height="72dip" android:layout_margin="3dip" android:layout_width="72dip" android:scaletype="centerCrop">
<textview android:id="#+id/text" android:layout_gravity="left|center_vertical" android:layout_height="wrap_content" android:layout_marginleft="20dip" android:layout_width="fill_parent" android:textsize="22sp">
For the Example above you need to download the library universal image loader you can download the library ... happy coding :)

you didn't use EndlessListView in your Fragment. As I looked your response, it includes pagination. So, you need to request with page number to use endless scroll.
This is just flow for Endless Listview. If your code still doesn't work, I hope you can learn sample projects after read this messages. I added only parts you need. Thanks
Endless scroll only shows limited data on listview. When user scroll down to bottom, it will get next limited data from server. So you need to add current_page paramater in your request. I don't know exactly your api.
First, you need variable for current_page which initialize with 0
You have to know when to stop. You response has total_page field for that. Save and add validation
Then you need to know when to request next page. For that,you already have codes in onScroll within EndlessListView. That code calculate and tell when user scroll down to bottom and it called
listener.loadData();
to request new data. But you still need to add listener for that. You already have
public void setListener(EndLessListener listener) {
this.listener = listener;
}
You need to create Interface with the name EndlessListener and implements in your fragment. EndlessListener Interface will include loadData() function that request to server. After that you need to add listener for the listview.
endlessListView.setListener(this);

Try Loading data when listview reaches it's end. Implement OnScrollListener in your fragment. Refer this link Android - ListView to load more items when reached end

You MUST use Paging 3 library to resolve all problems in simplest way.

ListView 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" >
<ListView
android:id="#+id/orderlistview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="center"
/>
</LinearLayout>
OrderList class
public class OrderList {
int _orderId;
int _orderincrement_id;
String _orderstatus;
String _orderdate;
String _ordership_to;
String _ordertotal;
String _ordercurrency_symbol;
// Empty constructor
public OrderList() {
}
// constructor
public OrderList(int _orderId, int _orderincrement_id, String _orderstatus,
String _orderdate, String _ordership_to, String _ordertotal,
String _ordercurrency_symbol) {
this._orderId = _orderId;
this._orderincrement_id = _orderincrement_id;
this._orderstatus = _orderstatus;
this._orderdate = _orderdate;
this._ordership_to = _ordership_to;
this._ordertotal = _ordertotal;
this._ordercurrency_symbol = _ordercurrency_symbol;
}
public int get_orderId() {
return _orderId;
}
public void set_orderId(int _orderId) {
this._orderId = _orderId;
}
public int get_orderincrement_id() {
return _orderincrement_id;
}
public void set_orderincrement_id(int _orderincrement_id) {
this._orderincrement_id = _orderincrement_id;
}
public String get_orderstatus() {
return _orderstatus;
}
public void set_orderstatus(String _orderstatus) {
this._orderstatus = _orderstatus;
}
public String get_orderdate() {
return _orderdate;
}
public void set_orderdate(String _orderdate) {
this._orderdate = _orderdate;
}
public String get_ordership_to() {
return _ordership_to;
}
public void set_ordership_to(String _ordership_to) {
this._ordership_to = _ordership_to;
}
public String get_ordertotal() {
return _ordertotal;
}
public void set_ordertotal(String _ordertotal) {
this._ordertotal = _ordertotal;
}
public String get_ordercurrency_symbol() {
return _ordercurrency_symbol;
}
public void set_ordercurrency_symbol(String _ordercurrency_symbol) {
this._ordercurrency_symbol = _ordercurrency_symbol;
}
}
Activity
public class OrderListFragment extends Fragment {
View rootView;
ListView lv;
List<OrderList> list ;
MyListAdapter adt;
DatabaseHandler db ;
ProgressDialog progress;
SharedPreferences pref;
public OrderListFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.fragmentorderlist, container,
false);
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
.permitAll().build();
StrictMode.setThreadPolicy(policy);
}
lv = (ListView) rootView.findViewById(R.id.orderlistview);
db = new DatabaseHandler(getActivity());
list = db.getAllOrderList();
if(list.size() == 0){
progress = new ProgressDialog(getActivity());
progress.setMessage("Fetching Data.....");
progress.setIndeterminate(true);
progress.setCancelable(false);
progress.show();
pref = PreferenceManager.getDefaultSharedPreferences(getActivity());
String customer_id = pref.getString("customer_id", null);
Log.v("log_tag", "customer_id"+customer_id);
if(customer_id != null){
Log.v("log_tag", "customer_id 2332 ::: "+customer_id);
new FetchOrderListData().execute(customer_id);
}
}
adt = new MyListAdapter(getActivity());
lv.setAdapter(adt);
lv.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> a, View v, int position,
long id) {
Bundle bundle = new Bundle();
bundle.putString("orderlist_increment_id", list.get(position).get_orderincrement_id()+"");
Fragment fragment = new OrderdetailFragment();
fragment.setArguments(bundle);
FragmentManager fragmentManager = OrderListFragment.this
.getActivity().getSupportFragmentManager();
FragmentTransaction mFragmentTransaction = fragmentManager
.beginTransaction();
mFragmentTransaction.addToBackStack(null);
mFragmentTransaction.replace(R.id.Frame_Layout, fragment)
.commit();
}
});
return rootView;
}
public class MyListAdapter extends BaseAdapter {
private LayoutInflater mInflater;
public MyListAdapter(Context context) {
mInflater = LayoutInflater.from(context);
}
public int getCount() {
return list.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(final int position, View convertView,
ViewGroup parent) {
convertView = mInflater.inflate(R.layout.custom_orderlistdata,
null);
TextView ordernumbertxt = (TextView) convertView
.findViewById(R.id.ordernumberTxt);
TextView orderdate = (TextView) convertView
.findViewById(R.id.orderdateTxt);
TextView orderamount = (TextView) convertView
.findViewById(R.id.orderAmountTxt);
TextView orderSatusTxt = (TextView) convertView
.findViewById(R.id.orderSatusTxt);
ordernumbertxt.setText(Html.fromHtml("<b>Order Number : </b>"+list.get(position).get_orderincrement_id()+""));
orderdate.setText(list.get(position).get_orderdate());
orderSatusTxt.setText(list.get(position).get_orderstatus());
String parts = list.get(position).get_ordertotal();
double d = Double.parseDouble(parts);
double dval = roundTwoDecimals(d);
orderamount.setText(Html.fromHtml("<b>Total : </b>"+list.get(position).get_ordercurrency_symbol()+" "+dval));
return convertView;
}
public double roundTwoDecimals(double d) {
DecimalFormat twoDForm = new DecimalFormat("#.##");
return Double.valueOf(twoDForm.format(d));
}
}
private class FetchOrderListData extends AsyncTask<String, Void, JSONObject> {
#Override
protected void onPreExecute() {
}
#Override
protected JSONObject doInBackground(String... args) {
JSONObject listSize = null;
Integer cust_id = Integer.parseInt(args[0]);
try {
listSize = DBAda.getAllOrderListData(cust_id);
////*** call your HTTP Service over here ***////
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return listSize;
}
protected void onPostExecute(JSONObject jsonObj) {
db = new DatabaseHandler(getActivity());
if (progress != null) {
progress.hide();
}
if (jsonObj == null) {
return;
}
JSONArray json;
try {
json = jsonObj.getJSONArray("records");
for (int i = 0; i < json.length(); i++) {
JSONObject jobj;
try {
jobj = json.getJSONObject(i);
int order_id = Integer.parseInt(jobj.getString("order_id").toString());
int order_IncrementId = Integer.parseInt(jobj.getString("increment_id").toString());
String orderStatus = jobj.getString("status");
String orderdate = jobj.getString("date");
String ordershipto = jobj.getString("ship_to");
String ordertotal = jobj.getString("order_total");
String ordersymbol = jobj.getString("currency_symbol");
//db.addWishlistItem(new WishList(entity_id,quentity,comment,name,short_description,thumbnails,itemId));
db.addOrderListItem(new OrderList(order_id, order_IncrementId, orderStatus, orderdate, ordershipto, ordertotal, ordersymbol));
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
} catch (JSONException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
lv = (ListView) rootView.findViewById(R.id.orderlistview);
db = new DatabaseHandler(getActivity());
list = db.getAllOrderList();
adt = new MyListAdapter(getActivity());
lv.setAdapter(adt);
}
}
}

GridView is not updated with notifyDataSetChanged()

I have an Activity with GridView, with images in it. The images are parsed from the SD card of the device. Once the Activity starts, images are downloaded to the SD card using AsyncTask.
The problem is that this GridView does not get updated when images are downloaded. I want this GridView to be updated if more images are added to the directory (i.e. if more images are downloaded). I have tried notifyDataSetChanged() and invalidateViews(), however they are not helping.
Here is my code for the MainActivity, Image adapter and AsyncTask. Please try to show me where I made the mistake.
MainActivity:
ImageAdapter ia = new ImageAdapter(this);
GridView gridView;
#Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.grid_layout);
gridView = (GridView) findViewById(R.id.grid_view);
// Instance of ImageAdapter Class
ImageAdapter iAdapter = new ImageAdapter(this);
gridView.setAdapter(iAdapter);
iAdapter.notifyDataSetChanged();
gridView.invalidateViews();
new ImageDownlader(AndroidGridLayoutActivity.this, this).execute(downloadUrl);
gridView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
// Sending image id to FullScreenActivity
Intent i = new Intent(getApplicationContext(), FullImageActivity.class);
// passing array index
i.putExtra("id", position);
startActivity(i);
}
});
getView() of Image Adapter:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView = new ImageView(mContext);
imageView.setImageBitmap(getImageByIndex(imageThumbnails, position));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setLayoutParams(new GridView.LayoutParams(155, 155));
return imageView;
}
ImageDownlader:
class ImageDownlader extends AsyncTask<String, Void, Void> {
private Context context;
public ImageDownlader(Context c){
context = c;
}
Sync s = new Sync();
#Override
protected Void doInBackground(String... param) {
// this is where images are downloaded to SD card
saveToSD ();
return null;
}
#Override
protected void onPreExecute() {
Log.i("Async-Example", "onPreExecute Called");
}
protected void onPostExecute()
{
Log.i("Async-Example", "onPostExecute Called");
}

The first, you should download Image from URL and return it.
import java.io.InputStream;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.util.Log;
import android.widget.ImageView;
public class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
ImageView bmImage;
public DownloadImageTask(ImageView bmImage) {
this.bmImage = bmImage;
}
protected Bitmap doInBackground(String... urls) {
String urldisplay = urls[0];
Bitmap mIcon11 = null;
try {
InputStream in = new java.net.URL(urldisplay).openStream();
mIcon11 = BitmapFactory.decodeStream(in);
} catch (Exception e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return mIcon11;
}
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
}
}
The second, create an Adapter
import java.util.List;
import vn.mve.obj.Video;
import vn.mve.util.DownloadImageTask;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import vn.mve.e4u.Detail;
import vn.mve.e4u.R;
public class VideoAdapter extends BaseAdapter {
private List<Video> list;
private Context context;
private LayoutInflater inflater;
public VideoAdapter(Context context, List<Video> list) {
this.context = context;
this.list = list;
inflater = LayoutInflater.from(context);
}
#Override
public int getCount() {
return list.size();
}
#Override
public Object getItem(int position) {
return list.get(position);
}
#Override
public long getItemId(int position) {
return 0;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = inflater.inflate(R.layout.layout_video_gridview, parent, false);
ImageView iv_thumb = (ImageView) view.findViewById(R.id.iv_thumb);
new DownloadImageTask(iv_thumb).execute(list.get(position).getThumbnail());
TextView tv_title = (TextView) view.findViewById(R.id.tv_title);
tv_title.setText(list.get(position).getTitle());
LinearLayout item = (LinearLayout) view.findViewById(R.id.item);
item.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(context, Detail.class);
intent.putExtra("ID", list.get(position).getId());
context.startActivity(intent);
}
});
return view;
}
}
Right here:
new DownloadImageTask(iv_thumb).execute(list.get(position).getThumbnail());
You can Create an Instance of DownloadImageTask, after that you can get an Image like that:
imageTask = new DownloadImageTask(iv_thumb).execute(list.get(position).getThumbnail());
Bitmap myImage = imageTask.get(); // Please put in try-catch
The last, in MainActivity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
List<Video> list = null;
MVideo mVideo = new MVideo(getApplicationContext());
list = mVideo.getList(VideoType.GET_ALL);
VideoAdapter adapter = new VideoAdapter(this, list);
if (list != null) {
GridView gvVideo = (GridView) findViewById(R.id.gv_video);
gvVideo.setAdapter(adapter);
}
}
Hope this will help you!

How to handle null pointer exception in android

I am trying to make photo gallery application.But I am having following error and my program will crashed.Also I am having error to this line :
imageView.setImageResource(pics[arg2]);
error
09-03 16:45:22.618: E/AndroidRuntime(443): Uncaught handler: thread main exiting due to uncaught exception
09-03 16:45:22.628: E/AndroidRuntime(443): java.lang.NullPointerException
09-03 16:45:22.628: E/AndroidRuntime(443): at com.example.myfirstapplication.setwall$1.onItemClick(setwall.java:40)
09-03 16:45:22.648: E/dalvikvm(443): Unable to open stack trace file '/data/anr/traces.txt': Permission denied
Here is my code:
package com.sai.samples.views;
import android.app.Activity;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;
public class GalleryView extends Activity {
Integer[] pics = {
R.drawable.antartica1,
R.drawable.antartica2,
R.drawable.antartica3,
R.drawable.antartica4,
R.drawable.antartica5,
R.drawable.antartica6,
R.drawable.antartica7,
R.drawable.antartica8,
R.drawable.antartica9,
R.drawable.antartica10
};
ImageView imageView;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Gallery ga = (Gallery)findViewById(R.id.Gallery01);
ga.setAdapter(new ImageAdapter(this));
imageView = (ImageView)findViewById(R.id.ImageView01);
ga.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
Toast.makeText(getBaseContext(),
"You have selected picture " + (arg2+1) + " of Antartica",
Toast.LENGTH_SHORT).show();
imageView.setImageResource(pics[arg2]);
}
});
}
public class ImageAdapter extends BaseAdapter {
private Context ctx;
int imageBackground;
public ImageAdapter(Context c) {
ctx = c;
TypedArray ta = obtainStyledAttributes(R.styleable.Gallery1);
imageBackground = ta.getResourceId(R.styleable.Gallery1_android_galleryItemBackground, 1);
ta.recycle();
}
#Override
public int getCount() {
return pics.length;
}
#Override
public Object getItem(int arg0) {
return arg0;
}
#Override
public long getItemId(int arg0) {
return arg0;
}
#Override
public View getView(int arg0, View arg1, ViewGroup arg2) {
ImageView iv = new ImageView(ctx);
iv.setImageResource(pics[arg0]);
iv.setScaleType(ImageView.ScaleType.FIT_XY);
iv.setLayoutParams(new Gallery.LayoutParams(150,120));
iv.setBackgroundResource(imageBackground);
return iv;
}
}
}
here is my main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Gallery
android:id="#+id/Gallery01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></Gallery>
<ImageView
android:id="#+id/ImageView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"></ImageView>
</LinearLayout>

This line probably returns null :
imageView = (ImageView)findViewById(R.id.ImageView01);
Check if the ImageView id is correct, and try to clean and rebuild your project if the error persists.

I have used this code for creating a gallery of images,
public class GalleryViewActivity extends Activity
{
GridView gridView;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
gridView = (GridView)findViewById(R.id.gridView);
gridView.setAdapter(new ImageAdapter(this));
}
}
class ImageAdapter extends BaseAdapter
{
ArrayList<String> images;
private Context mContext;
public ImageAdapter(Context c)
{
mContext = c;
}
public int getCount()
{
return mThumbIds.length;
}
public Object getItem(int position)
{
return null;
}
public long getItemId(int position)
{
return 0;
}
// create a new ImageView for each item referenced by the Adapter
public View getView(final int position, View convertView, ViewGroup parent)
{
ImageView imageView;
if (convertView == null)
{ // if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
}
else
{
imageView = (ImageView) convertView;
}
imageView.setClickable(true);
imageView.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
Intent i = new Intent(v.getContext(), showImageClass.class);
Toast.makeText(v.getContext(), mThumbIds.toString() + " Clicked", 5000).show();
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.putExtra("imageName", mThumbIds[position]);
v.getContext().startActivity(i);
}
});
// imageView.setImageDrawable(images);
// imageView.setImageBitmap(images);
// imageView.setImageResource(images[]);
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
// references to images
private Integer[] mThumbIds =
{
R.drawable.abc,
R.drawable.def,
R.drawable.klm,
R.drawable.pqr,
R.drawable.rst,
R.drawable.wxy,
R.drawable.xyz,
};
}

First create a class GalleryViewActivity
public class GalleryViewActivity extends Activity
{
GridView gridView;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
gridView = (GridView)findViewById(R.id.gridView);
gridView.setAdapter(new ImageAdapter(this));
}
}
class ImageAdapter extends BaseAdapter
{
ArrayList<String> images;
private Context mContext;
public ImageAdapter(Context c)
{
mContext = c;
}
public int getCount()
{
return mThumbIds.length;
}
public Object getItem(int position)
{
return null;
}
public long getItemId(int position)
{
return 0;
}
// create a new ImageView for each item referenced by the Adapter
public View getView(final int position, View convertView, ViewGroup parent)
{
ImageView imageView;
if (convertView == null)
{ // if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
}
else
{
imageView = (ImageView) convertView;
}
imageView.setClickable(true);
imageView.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
Intent i = new Intent(v.getContext(), showImageClass.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.putExtra("position", "" + position);
v.getContext().startActivity(i);
}
});
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
// references to images
private Integer[] mThumbIds =
{
R.drawable.abc,
R.drawable.def,
R.drawable.klm,
R.drawable.pqr,
R.drawable.rst,
R.drawable.wxy,
R.drawable.xyz,
};
}
Dont forget to add images in the drawable folder. the image should be same as you mentioned in the mThumbIds array, like i have used abc.jpg, def.jpg and so on..
Then you need to create a showImage.java class, here you take a imageview to show the large view of image clicked..
public class showImageClass extends Activity
{
private Integer[] mThumbIds =
{
R.drawable.abc,
R.drawable.def,
R.drawable.klm,
R.drawable.pqr,
R.drawable.rst,
R.drawable.wxy,
R.drawable.xyz,
};
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.showimage);
int position = Integer.parseInt(this.getIntent().getStringExtra("position"));
ImageView jpgView = (ImageView)findViewById(R.id.imageView);
jpgView.setImageResource(mThumbIds[position]);
}
}
This code has worked for me, it will definitely work..
Dont forget to add the relavent images and import the class libraries that are needed.
Mention both the activities in android manifest file

how to view next image in imageview?

Hi I have images in grid view. when i click my grid view images, it's display in full screen. if i want view another image go back in grid view then select another image view in full screen. i feel it's hard one.. so i am trying to view images full screen view using to swipe....no idea how to create this method please guide me and give some nice codes also...
This is my working app screen shot:
source code: 1. ImageViewExample.java
public class ImageViewExample extends Activity {
/** Called when the activity is first created. */
private Cursor imagecursor, actualimagecursor;
private int image_column_index, actual_image_column_index;
GridView imagegrid;
private int count;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init_phone_image_grid();
}
private void init_phone_image_grid() {
String[] img = { MediaStore.Images.Thumbnails._ID };
imagecursor = managedQuery(
MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, img, null,
null, MediaStore.Images.Thumbnails.IMAGE_ID + "");
image_column_index = imagecursor
.getColumnIndexOrThrow(MediaStore.Images.Thumbnails._ID);
count = imagecursor.getCount();
imagegrid = (GridView) findViewById(R.id.PhoneImageGrid);
imagegrid.setAdapter(new ImageAdapter(getApplicationContext()));
imagegrid.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView parent, View v,int position, long id) {
System.gc();
String[] proj = { MediaStore.Images.Media.DATA };
actualimagecursor = managedQuery(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, proj,
null, null, null);
actual_image_column_index = actualimagecursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
actualimagecursor.moveToPosition(position);
String i = actualimagecursor.getString(actual_image_column_index);
System.gc();
Intent intent = new Intent(getApplicationContext(), ViewImage.class);
intent.putExtra("filename", i);
startActivity(intent);
}
});
}
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context c) {
mContext = c;
}
public int getCount() {
return count;
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position,View convertView,ViewGroup parent) {
System.gc();
ImageView i = new ImageView(mContext.getApplicationContext());
if (convertView == null) {
imagecursor.moveToPosition(position);
int id = imagecursor.getInt(image_column_index);
i.setImageURI(Uri.withAppendedPath(MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI, ""+ id));
i.setScaleType(ImageView.ScaleType.CENTER_CROP);
i.setLayoutParams(new GridView.LayoutParams(92, 92));
}
else {
i = (ImageView) convertView;
}
return i;
}
}
}
ViewImage.java
public class ViewImage extends Activity {
private String filename;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
System.gc();
Intent i = getIntent();
Bundle extras = i.getExtras();
BitmapFactory.Options bfo = new BitmapFactory.Options();
bfo.inSampleSize = 2;
filename = extras.getString("filename");
ImageView iv = new ImageView(getApplicationContext());
Bitmap bm = BitmapFactory.decodeFile(filename, bfo);
iv.setImageBitmap(bm);
setContentView(iv);
}
}

After getting id of selected image, implement this..
// this Class For Grid view images
package com.thumbnailview;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.Toast;
public class Activity_ThumbView extends Activity
{
GridView gridview;
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(new ImageAdapter(this));
gridview.setOnItemClickListener(new OnItemClickListener()
{
public void onItemClick(AdapterView<?> parent, View v, int position, long id)
{
Toast.makeText(Activity_ThumbView.this, "" + position, 2).show();
id=parent.getPositionForView(v);
Intent i=new Intent(Activity_ThumbView.this,Activity_ImageView.class);
i.putExtra("position", position);
startActivity(i);
finish();
}
});
}
public class ImageAdapter extends BaseAdapter
{
Context context;
public ImageAdapter(Context c )
{
context = c ;
}
public int getCount() {
return mThumbIds.length;
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return mThumbIds[position];
}
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null)
{
imageView = new ImageView(context);
imageView.setLayoutParams(new GridView.LayoutParams(75, 75));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
}
else
{
imageView = (ImageView) convertView;
}
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
}
public static Integer[] mThumbIds = {
R.drawable.a,R.drawable.icon,
R.drawable.b, R.drawable.s,
R.drawable.c, R.drawable.r,
R.drawable.d, R.drawable.q,
R.drawable.e, R.drawable.p,
R.drawable.f, R.drawable.o,
R.drawable.g, R.drawable.n,
R.drawable.h, R.drawable.m,
R.drawable.i, R.drawable.l,
R.drawable.j, R.drawable.k,
R.drawable.t,R.drawable.y,
R.drawable.u,R.drawable.x,
R.drawable.v,R.drawable.s,
R.drawable.cd,R.drawable.z,
R.drawable.bc,R.drawable.ab
};
}
// This Flip image Class
package com.thumbnailview;
import java.io.IOException;
import android.app.Activity;
import android.app.WallpaperManager;
import android.content.Intent;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.GestureDetector.OnGestureListener;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.ViewFlipper;
public class Activity_ImageView extends Activity
{
ImageView thumb_imgview;
ViewFlipper viewFlipper;
Button b_wall;
Button b_home;
// Animation a,b;
private static final int SWIPE_MIN_DISTANCE = 120;
private static final int SWIPE_MAX_OFF_PATH = 250;
private static final int SWIPE_THRESHOLD_VELOCITY = 200;
private GestureDetector gestureDetector;
View.OnTouchListener gestureListener;
int j;
WallpaperManager myWall;
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.image);
j=getIntent().getExtras().getInt("position");
myWall = WallpaperManager.getInstance(getApplicationContext());
b_wall=(Button) findViewById(R.id.button3);
b_home=(Button) findViewById(R.id.button1);
thumb_imgview=(ImageView) findViewById(R.id.thumb_txt_image);
thumb_imgview.setImageResource(Activity_ThumbView.mThumbIds[j]);
gestureDetector = new GestureDetector(new MyGestureDetector());
b_wall.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
myWall.setResource(Activity_ThumbView.mThumbIds[j]);
} catch (IOException e) {
e.printStackTrace();
}
}
});
b_home.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent i=new Intent(Activity_ImageView.this,Activity_ThumbView.class);
startActivity(i);
finish();
}
});
}
public class MyGestureDetector extends SimpleOnGestureListener implements OnGestureListener
{
public boolean onFling(MotionEvent m1, MotionEvent m2, float velocityX, float velocityY)
{
try
{
if (Math.abs(m1.getY() - m2.getY()) > SWIPE_MAX_OFF_PATH)
return false;
if(m1.getX() - m2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY)
{
if(Activity_ThumbView.mThumbIds.length>j)
{
j++;
thumb_imgview.setImageResource(Activity_ThumbView.mThumbIds[j]);
}
}
else if (m2.getX() - m1.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY)
{
if(j>0)
{
j--;
thumb_imgview.setImageResource(Activity_ThumbView.mThumbIds[j]);
}
}
}
catch (Exception e)
{
}
return false;
}
}
public boolean onTouchEvent(MotionEvent event)
{
if (gestureDetector.onTouchEvent(event))
return true;
else
return false;
}
}

Implement OnGestureListener in ViewImage activity and capture swipe from user.
For displaying previous or next image, use cursor.

Store all image filenames in array when you are populating into Gridview and then pass that array to another view from that array you can get all images instead of go back to gridview for selecting images..

The easiest way to do this is indeed like RajaReddy P said: create an array with the filenames/urls pass it to the ViewImage activity...
For the ViewImage activity I really would use the ViewPager! Really easy to implement and the swiping is handled for you!
More about viewpager:
http://android-developers.blogspot.com/2011/08/horizontal-view-swiping-with-viewpager.html