Posso usare il cercapersone con vista (non con frammenti)

Sto usando ViewPagerper scorrere tra Fragments, ma posso usare ViewPagerper scorrere tra un Viewssemplice layout XML?

Questa è la mia pagina Adapterper ViewPager che viene utilizzata per scorrere tra i frammenti:

import java.util.List;

import com.app.name.fragments.TipsFragment;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.FragmentTransaction;
import android.view.ViewGroup;

public class PageAdapter extends FragmentPagerAdapter {

    /**
     *
     */
    List<Fragment> fragments;
    public PageAdapter(FragmentManager fm,List<Fragment> frags) {
        super(fm);
        fragments = frags;

    }

    @Override
    public Fragment getItem(int arg0) {
        // TODO Auto-generated method stub
        return TipsFragment.newInstance(0, 0);
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return 4;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        FragmentManager manager = ((Fragment) object).getFragmentManager();
        FragmentTransaction trans = manager.beginTransaction();
        trans.remove((Fragment) object);
        trans.commit();

        super.destroyItem(container, position, object);
    }

}

E questo è il mio frammento di punta:

public class TipsFragment extends Fragment
{
    public static TipsFragment newInstance(int image,int content)
    {
        TipsFragment fragment = new TipsFragment();
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.tip_layout, null);
        return view;
    }
}

Come posso modificare il mio codice per lavorare con Views invece che con Fragment?

È necessario sostituire questi due metodi anziché getItem():

@Override
public Object instantiateItem(ViewGroup collection, int position) {
    View v = layoutInflater.inflate(...);
    ...
    collection.addView(v,0);
    return v;
}

@Override
public void destroyItem(ViewGroup collection, int position, Object view) {
    collection.removeView((View) view);
}

Usa questo esempio

È possibile utilizzare un unico layout XML che annida le viste figlio.

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent">

            <LinearLayout
                android:id="@+id/page_one"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical" >
                        <TextView
                        android:text="PAGE ONE IN"
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:textColor="#fff"
                        android:textSize="24dp"/>
            </LinearLayout>

            <LinearLayout
                android:id="@+id/page_two"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical" >
                        <TextView
                        android:text="PAGE TWO IN"
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:textColor="#fff"
                        android:textSize="24dp"/>
            </LinearLayout>

    </android.support.v4.view.ViewPager>
</LinearLayout>

MA ... devi gestirlo anche con un adattatore. Qui restituiamo l'ID della vista trovata senza gonfiare nessun altro layout.

class WizardPagerAdapter extends PagerAdapter {

    public Object instantiateItem(ViewGroup collection, int position) {

        int resId = 0;
        switch (position) {
        case 0:
            resId = R.id.page_one;
            break;
        case 1:
            resId = R.id.page_two;
            break;
        }
        return findViewById(resId);
    }

    @Override
    public int getCount() {
        return 2;
    }

    @Override
    public boolean isViewFromObject(View arg0, Object arg1) {
        return arg0 == arg1;
    }

    @Override public void destroyItem(ViewGroup container, int position, Object object) {
        // No super
    }
}

// Imposta l'adattatore ViewPager

WizardPagerAdapter adapter = new WizardPagerAdapter();
ViewPager pager = (ViewPager) findViewById(R.id.pager);
pager.setAdapter(adapter);

Abbiamo creato una sottoclasse molto semplice di ViewPagerquella che usiamo a volte.

/**
 * View pager used for a finite, low number of pages, where there is no need for
 * optimization.
 */
public class StaticViewPager extends ViewPager {

    /**
     * Initialize the view.
     *
     * @param context
     *            The application context.
     */
    public StaticViewPager(final Context context) {
        super(context);
    }

    /**
     * Initialize the view.
     *
     * @param context
     *            The application context.
     * @param attrs
     *            The requested attributes.
     */
    public StaticViewPager(final Context context, final AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onAttachedToWindow() {
        super.onAttachedToWindow();

        // Make sure all are loaded at once
        final int childrenCount = getChildCount();
        setOffscreenPageLimit(childrenCount - 1);

        // Attach the adapter
        setAdapter(new PagerAdapter() {

            @Override
            public Object instantiateItem(final ViewGroup container, final int position) {
                return container.getChildAt(position);
            }

            @Override
            public boolean isViewFromObject(final View arg0, final Object arg1) {
                return arg0 == arg1;

            }

            @Override
            public int getCount() {
                return childrenCount;
            }

            @Override
            public void destroyItem(final View container, final int position, final Object object) {}
        });
    }

}

Questa classe non ha bisogno di un adattatore in quanto caricherà le viste dal layout. Per usarlo i tuoi progetti, basta usarlo al posto di android.support.v4.view.ViewPager.

Tutte le cose fantasiose continueranno a funzionare, ma non è necessario preoccuparsi degli adattatori.

Sulla base delle risposte precedenti, ho fatto la seguente lezione per raggiungere questo obiettivo in modo corretto e chiaro (spero):

public class MyViewPagerAdapter extends PagerAdapter {

    ArrayList<ViewGroup> views;
    LayoutInflater inflater;

    public MyViewPagerAdapter(ActionBarActivity ctx){
        inflater = LayoutInflater.from(ctx);
        //instantiate your views list
        views = new ArrayList<ViewGroup>(5);
    }

    /**
     * To be called by onStop
     * Clean the memory
     */
    public void release(){
     views.clear();
        views = null;
    }

    /**
     * Return the number of views available.
     */
    @Override
    public int getCount() {
        return 5;
    }

    /**
     * Create the page for the given position. The adapter is responsible
     * for adding the view to the container given here, although it only
     * must ensure this is done by the time it returns from
     * {@link #finishUpdate(ViewGroup)}.
     *
     * @param container The containing View in which the page will be shown.
     * @param position The page position to be instantiated.
     * @return Returns an Object representing the new page. This does not
     *         need to be a View, but can be some other container of
     *         the page.  ,container
     */
    public Object instantiateItem(ViewGroup container, int position) {
        ViewGroup currentView;
        Log.e("MyViewPagerAdapter", "instantiateItem for " + position);
        if(views.size()>position&&views.get(position) != null){
            Log.e("MyViewPagerAdapter",
                  "instantiateItem views.get(position) " +
                  views.get(position));
            currentView = views.get(position);
        }
        else{
            Log.e("MyViewPagerAdapter", "instantiateItem need to create the View");
            int rootLayout = R.layout.view_screen;
            currentView = (ViewGroup) inflater.inflate(rootLayout, container, false);

            ((TextView)currentView.findViewById(R.id.txvTitle)).setText("My Views " + position);
            ((TextView)currentView.findViewById(R.id.btnButton)).setText("Button");
            ((ImageView)currentView.findViewById(R.id.imvPicture)).setBackgroundColor(0xFF00FF00);
        }
        container.addView(currentView);
        return currentView;
    }

    /**
     * Remove a page for the given position. The adapter is responsible
     * for removing the view from its container, although it only must ensure
     * this is done by the time it returns from {@link #finishUpdate(ViewGroup)}.
     *
     * @param container The containing View from which the page will be removed.
     * @param position The page position to be removed.
     * @param object The same object that was returned by
     * {@link #instantiateItem(View, int)}.
     */
    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        container.removeView((View)object);

    }

    /**
     * Determines whether a page View is associated with a specific key object
     * as returned by {@link #instantiateItem(ViewGroup, int)}. This method is
     * required for a PagerAdapter to function properly.
     *
     * @param view   Page View to check for association with <code>object</code>
     * @param object Object to check for association with <code>view</code>
     * @return true if <code>view</code> is associated with the key object <code>object</code>
     */
    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view==((View)object);
    }
}

E devi impostarlo nella tua attività:

public class ActivityWithViewsPaged extends ActionBarActivity {

    /**
     * The page Adapter: Manage the list of views (in fact here, its fragments)
     * And send them to the ViewPager
     */
    private MyViewPagerAdapter pagerAdapter;

    /**
     * The ViewPager is a ViewGroup that manage the swipe from left
     * to right to left.
     * Like a listView with a gesture listener...
     */
    private ViewPager viewPager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_with_views);

        // Find the viewPager
        viewPager = (ViewPager) super.findViewById(R.id.viewpager);

        // Instantiate the PageAdapter
        pagerAdapter = new MyViewPagerAdapter(this);

        // Affectation de l'adapter au ViewPager
        viewPager.setAdapter(pagerAdapter);
        viewPager.setClipToPadding(false);
        viewPager.setPageMargin(12);

        // Add animation when the page are swiped
        // this instanciation only works with honeyComb and more
        // if you want it all version use AnimatorProxy of the nineoldAndroid lib
        //@see:http://stackoverflow.com/questions/15767729/backwards-compatible-pagetransformer
        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
            viewPager.setPageTransformer(true, new PageTransformer());
        }
    }

    @Override
    protected void onStop() {
        super.onStop();
        pagerAdapter.release();
    }

Dove i file XML sono evidenti view_screen.xml:

<xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/screen"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

 <TextView
        android:id="@+id/txvTitle"
        android:layout_width="wrap_content"
        android:layout_gravity="center"
        android:layout_height="wrap_content"
        android:layout_marginBottom="5dp"
        android:layout_marginTop="5dp"
        android:shadowColor="#FF00FF"
        android:shadowDx="10"
        android:shadowDy="10"
        android:shadowRadius="5"
        android:textSize="32dp"
        android:textStyle="italic"
        android:background="#FFFFF000"/>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#FFFF00F0">
        <TextView
            android:id="@+id/txvLeft"
            android:layout_width="wrap_content"
            android:layout_gravity="left"
            android:layout_height="wrap_content"
            android:layout_marginBottom="5dp"
            android:layout_marginTop="5dp"/>
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"/>
        <TextView
            android:id="@+id/txvRight"
            android:layout_width="wrap_content"
            android:layout_gravity="right"
            android:layout_height="wrap_content"
            android:layout_marginBottom="5dp"
            android:layout_marginTop="5dp"/>
    </LinearLayout>
    <Button
        android:id="@+id/btnButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"/>
    <ImageView
        android:id="@+id/imvPicture"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_gravity="center"/>
</LinearLayout>

E ActivtyMain ha il seguente layout:

<?xml version="1.0" encoding="utf-8"?>

<android.support.v4.view.ViewPager
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:paddingLeft="24dp"
    android:paddingRight="24dp"
    android:id="@+id/viewpager"
    android:background="#FF00F0F0">
</android.support.v4.view.ViewPager>

Un grande ringraziamento a Brian e Nicholas per la risposta, spero di aggiungere alcune informazioni più chiare e di evidenziare alcune buone pratiche per questa funzione.

Mi piacerebbe approfondire la risposta di @Nicholas, puoi ottenere le visualizzazioni per id o se sono aggiunte dinamicamente basta ottenere la vista direttamente data la sua posizione

class WizardPagerAdapter extends PagerAdapter {

    public Object instantiateItem(View collection, int position) {

        View v = pager.getChildAt(position);

        return v;
    }

    @Override
    public int getCount() {
        return 3;
    }

    @Override
    public boolean isViewFromObject(View arg0, Object arg1) {
        return arg0 == ((View) arg1);
    }
}

Vorrei aggiungere la mia soluzione qui. Dato che non è necessario utilizzare frammenti, è comunque possibile creare un oggetto PagerAdapterche si attacca viewsinvece che fragmentsa ViewPager.

Estendi PagerAdapteranzichéFragmentPagerAdapter

public class CustomPagerAdapter extends PagerAdapter {

  private Context context;

  public CustomPagerAdapter(Context context) {
    super();
    this.context = context;
  }


  @Override
  public Object instantiateItem(ViewGroup collection, int position) {
    LayoutInflater inflater = LayoutInflater.from(context);
    View view = null;
    switch (position){
      case 0:
        view = MemoryView.getView(context, collection);
        break;
      case 1:
        view = NetworkView.getView(context, collection);
        break;
      case 2:
        view = CpuView.getView(context, collection);
        break;
    }

    collection.addView(view);
    return view;
  }

  @Override
  public int getCount() {
    return 3;
  }

  @Override
  public boolean isViewFromObject(View view, Object object) {
    return view==object;
  }

  @Override
  public void destroyItem(ViewGroup collection, int position, Object view) {
    collection.removeView((View) view);
  }
}

Ora è necessario definire tre classi che restituiranno il valore viewsda gonfiare nel file viewpager. Simile a CpuViewte avrà MemoryViewe NetworkViewclassi. Ognuno di essi gonfia i rispettivi layout.

public class CpuView {

public static View getView(Context context, ViewGroup collection) {

    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context
        .LAYOUT_INFLATER_SERVICE);
    return inflater.inflate(R.layout.debugger_cpu_layout, collection, false);
  }
}

E infine un layout che verrà gonfiato in ciascuna delle viste

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#000000"
        android:text="CPU"/>
</LinearLayout>

PS: Il motivo per cui ho scritto questa risposta è perché tutte le soluzioni fornite qui sembrano funzionare bene, ma stanno gonfiando i layout nella stessa classe PagerAdapter. Per progetti di grandi dimensioni diventa difficile mantenere se il loro è un sacco di codice relativo ai layout gonfiati. Ora in questo esempio tutte le viste hanno classi e layout separati. Quindi il progetto può essere facilmente mantenuto.

sì ... puoi usare Visualizza invece di Frammento in viewpager. Qui puoi trovare l'intero esempio che ti aiuterà a ottenere Viewpager senza frammenti. Consulta questa documentazione.

https://www.bignerdranch.com/blog/viewpager-without-fragments/