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As documented by Google, the Gallery class was deprecated in API level 16. This widget is no longer supported. Other horizontally scrolling widgets include HorizontalScrollView and ViewPager from the support library. So I used ViewPager as an alternative to the Gallery class.
My goal to finally achieve an infinite scrolling image ViewPager with text descriptions. I used the below code to achieve the image ViewPager with text describing each image but how do I apply Infinite Scrolling to a ViewPager?
I have not worked with ViewPager before so please try to provide detailed code if possible.
activity_main.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<android.support.v4.view.ViewPager
android:id="@+id/myimagepager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
custom_pager.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="center_horizontal">
<ImageView
android:id="@+id/myimage"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_margin="5dp"
android:layout_weight="2" />
<TextView
android:id="@+id/image_text"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
</LinearLayout>
ImagePager:
public class ImagePager extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ImagePagerAdapter adapter = new ImagePagerAdapter(this, imageArra, stringArray );
ViewPager myPager = (ViewPager) findViewById(R.id.myimagepager);
myPager.setAdapter(adapter);
myPager.setCurrentItem(0);
}
private int imageArra[] = { R.drawable.a, R.drawable.b,R.drawable.c,
R.drawable.d,R.drawable.e,R.drawable.f,
R.drawable.g, R.drawable.h, R.drawable.i};
private String[] stringArray = new String[] { "Image a", "Image b","Image c"
"Image d","Image e","Image f",
"Image g","Image h","Image i"};
}
ImagePagerAdapter:
public class ImagePagerAdapter extends PagerAdapter {
Activity activity;
int imageArray[];
String[] stringArray;
public ImagePagerAdapter(Activity act, int[] imgArra, String[] stringArra) {
imageArray = imgArra;
activity = act;
stringArray = stringArra;
}
public int getCount() {
return imageArray.length;
}
public Object instantiateItem(View collection, int position) {
LayoutInflater inflater = (LayoutInflater)collection.getContext
().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View layout = inflater.inflate(R.layout.custom_pager, null);
ImageView im=(ImageView) layout.findViewById(R.id.myimage);
im.setImageResource(imageArray[position]);
TextView txt=(TextView) layout.findViewById(R.id.image_text);
txt.setText(stringArray[position]);
((ViewPager) collection).addView(layout, 0);
return layout;
}
@Override
public void destroyItem(View arg0, int arg1, Object arg2) {
((ViewPager) arg0).removeView((View) arg2);
}
@Override
public boolean isViewFromObject(View arg0, Object arg1) {
return arg0 == ((View) arg1);
}
@Override
public Parcelable saveState() {
return null;
}
}
714
I had the same problem, but I was able to find a way to solve it - the code can be found on github.
If you copy the classes InfiniteViewPager and InfinitePagerAdapter into your project, you can achieve infinite (wrapped) scrolling with some small changes.
In your Activity, wrap your PagerAdapter with an InfinitePagerAdapter:
PagerAdapter adapter = new InfinitePagerAdapter(new ImagePagerAdapter(this, imageArra, stringArray));
Change the ViewPager in the activity XML to be an InfiniteViewPager:
<com.antonyt.infiniteviewpager.InfiniteViewPager
android:id="@+id/myimagepager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
You can rename the classes to whatever you want. This code only works if you have at least three pages (you have nine in your example code, so it will work fine for that).
52
I think my solution is simpler.
Attention to my array of images structure:
Item 0 => last image
Item count()-1 => first image
The trick is on onPageScrollStateChanged:
When user scrolls to last item -> the pager jumps without animation to first image (position = 1)
When user scrolls to first item -> the pager jumps without animation to last image (position = count - 2)
public class InfiniteScrollingActivity extends ActionBarActivity {
private ViewPager pager;
private MyAdapter adapter;
int[] promoImageIds = new int[]{R.drawable.cover6, R.drawable.cover1, R.drawable.cover2, R.drawable.cover3, R.drawable.cover4, R.drawable.cover5, R.drawable.cover6, R.drawable.cover1 };
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_test);
adapter = new MyAdapter(getSupportFragmentManager(), promoImageIds);
pager = (ViewPager)findViewById(R.id.pager);
pager.setAdapter(adapter);
pager.setCurrentItem( 1 );
pager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageSelected(int index) {
Log.v( "onPageSelected", String.valueOf( index ) );
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// Log.v("onPageScrolled", "");
}
@Override
public void onPageScrollStateChanged(int state) {
Log.v("onPageScrollStateChanged", String.valueOf(state));
if (state ==ViewPager.SCROLL_STATE_IDLE) {
int index = pager.getCurrentItem();
if ( index == 0 )
pager.setCurrentItem( adapter.getCount() - 2, false );
else if ( index == adapter.getCount() - 1 )
pager.setCurrentItem( 1 , false);
}
}
});
}
public static class MyAdapter extends FragmentPagerAdapter {
int[] promoImageIds;
public MyAdapter(FragmentManager fm, int[] promoImageIds){
super(fm);
this.promoImageIds = promoImageIds;
}
@Override
public int getCount(){
return promoImageIds.length;
}
@Override
public Fragment getItem(int position) {
return PromoFragment.newInstance( promoImageIds[position] );
}
}
public static class PromoFragment extends Fragment
{
int imageID;
static PromoFragment newInstance( int imageID)
{
PromoFragment f = new PromoFragment();
// Supply num input as an argument.
Bundle args = new Bundle();
args.putInt( "imageID", imageID );
f.setArguments(args);
return f;
}
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
imageID = getArguments() != null ? getArguments().getInt( "imageID" ) : null;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
ImageView v = (ImageView) inflater.inflate(R.layout.fragment_image, container, false);
v.setImageResource( imageID );
return v;
}
}
}
answered Oct 22 '22 06:10
i have already found a way by making simple trick , i hope it helps to you
import java.util.ArrayList;
import android.os.Bundle;
import android.app.Activity;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.Log;
public class ImagePager extends Activity {
String[] stringArray;
int[] imageArra;
ViewPager myPager;
Boolean isScrooled = false;
// use this array yo understand swipe left or right ?
ArrayList<Float> pos = new ArrayList<Float>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// put empty view at the beginnig and to end
imageArra = new int[] { 0, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher, 0 };
// put empty string at the beginnig and to end
stringArray = new String[] { "", "Image a", "Image b", "Image c",
"Image d", "Image e", "Image f", "Image g", "Image h",
"Image i", "" };
ImagePagerAdapter adapter = new ImagePagerAdapter(this, imageArra,
stringArray);
myPager = (ViewPager) findViewById(R.id.myimagepager);
myPager.setAdapter(adapter);
myPager.setCurrentItem(1);
myPager.setOnPageChangeListener(new OnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
Log.v("onPageSelected", String.valueOf(arg0));
pos.clear();
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
try {
// while scrolling i add ever pos to array
pos.add(arg1);
// if pos.get(0) > pos.get(pos.size() - 1)
// <----- swipe <-----
// we should check isScroll because setCurrent item is not a croll ?
if (pos.size() > 0)
if (arg0 == imageArra.length - 1
& pos.get(0) > pos.get(pos.size() - 1)
& isScrooled == true) {
try {
isScrooled = false;
myPager.setCurrentItem(1, false);
} catch (Exception e) {
Log.v("hata",
"<----- swipe <----- " + e.toString());
}
}
// ----> swipe ---->
else if (arg0 == 0
& pos.get(0) < pos.get(pos.size() - 1)
& isScrooled == true) {
try {
isScrooled = false;
myPager.setCurrentItem(imageArra.length - 1,
false);
} catch (Exception e) {
Log.v("hata",
"----> swipe ----> " + e.toString());
}
} else if (arg0 == 0 & pos.size() == 1
& isScrooled == true) {
try {
isScrooled = false;
myPager.setCurrentItem(imageArra.length - 1,
false);
} catch (Exception e) {
Log.v("hata",
"----> swipe ----> " + e.toString());
}
}
} catch (Exception e) {
Log.v("hata", e.toString());
}
}
@Override
public void onPageScrollStateChanged(int arg0) {
Log.v("onPageScrollStateChanged", String.valueOf(arg0));
// set is scrolling
isScrooled = true;
}
});
}
}
[EDIT 1]
import java.util.ArrayList;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.Log;
public class ImagePager extends Activity {
String[] stringArray;
int[] imageArra;
ViewPager myPager;
int scrollState;
Boolean isFirstVisitEnd= true,isFirstVisitBegin = true;
ArrayList<Integer> pos = new ArrayList<Integer>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageArra = new int[] { 0,R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher,
R.drawable.ic_launcher, R.drawable.ic_launcher, 0 };
stringArray = new String[] {"","Image a", "Image b", "Image c",
"Image d", "Image e", "Image f", "Image g", "Image h",
"Image i", "" };
ImagePagerAdapter adapter = new ImagePagerAdapter(this, imageArra,
stringArray);
myPager = (ViewPager) findViewById(R.id.myimagepager);
myPager.setAdapter(adapter);
myPager.setCurrentItem(1);
myPager.setOnPageChangeListener(new OnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
Log.v("onPageSelected", String.valueOf(arg0));
pos.clear();
if (arg0 == imageArra.length - 1)
isFirstVisitEnd = false;
else
isFirstVisitEnd = true;
if (arg0 == 0)
isFirstVisitBegin = false;
else
isFirstVisitBegin = true;
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
try {
pos.add(Integer.valueOf(arg2));
if (pos.size() > 0) {
//Log.v("onPageScrolled_arg2","arg0 : "+String.valueOf(arg0)+" ilk : "+pos.get(0).toString()+" son : " +pos.get(pos.size() - 1).toString()+ " "+ String.valueOf(pos.get(0)-(pos.get(pos.size() - 1)))+" isFirstVisitEnd: "+String.valueOf(isFirstVisitEnd.booleanValue()) );
// <----- swipe <-----
if (arg0 == imageArra.length - 2& (pos.get(pos.size() - 1) -pos.get(0) < 100)& scrollState == 2 & isFirstVisitEnd == false) {
myPager.setCurrentItem(1, false);
}
//Log.v("onPageScrolled_arg2","arg0 : "+String.valueOf(arg0)+" ilk : "+pos.get(0).toString()+" son : " +pos.get(pos.size() - 1).toString()+ " "+ String.valueOf(pos.get(0)-(pos.get(pos.size() - 1)))+" isFirstVisitbegin: "+String.valueOf(isFirstVisitBegin.booleanValue()) );
if (arg0 == 0 & (pos.get(pos.size() - 1) -pos.get(0) > -100)& scrollState == 2 & isFirstVisitBegin == false) {
myPager.setCurrentItem(imageArra.length - 2, false);
}
}
} catch (Exception e) {
Log.v("hata", e.toString());
}
}
@Override
public void onPageScrollStateChanged(int arg0) {
Log.v("onPageScrollStateChanged", String.valueOf(arg0));
scrollState =arg0;
}
});
}
}
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