Как создать фрагмент на методе instantiateItem? ⇐ Android

[Anonymous]

Я очень новичок в программировании Android, и я пытаюсь сделать класс AntantiateItem в моем SlidingTabsbasicFragment , чтобы вернуть фрагмент моих разговоров Fragment .
По моему мнению, мои классовые разговоры возвращают фрагмент, который будет мгновенно. Но вместо этого ничто не показывает на второй странице.@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.v("Logs", "first");

if (savedInstanceState == null) {
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
SlidingTabsBasicFragment fragment = new SlidingTabsBasicFragment();
transaction.replace(R.id.sample_content_fragment, fragment);
//ConversationsFragment fragment = new ConversationsFragment();
//transaction.replace(R.id.sample_content_fragment, new ConversationsFragment());
transaction.commit();
}
}
< /code>
slindtabsbasicfragment: < /p>
package com.example.android.slidingtabsbasic;

import com.example.android.common.logger.Log;
import com.example.android.common.view.SlidingTabLayout;

import android.content.Context;
import android.os.Bundle;
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.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.util.SparseArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.TextView;

/**
* A basic sample which shows how to use {@link com.example.android.common.view.SlidingTabLayout}
* to display a custom {@link ViewPager} title strip which gives continuous feedback to the user
* when scrolling.
*/
public class SlidingTabsBasicFragment extends Fragment {

static final String LOG_TAG = "SlidingTabsBasicFragment";

/**
* A custom {@link ViewPager} title strip which looks much like Tabs present in Android v4.0 and
* above, but is designed to give continuous feedback to the user when scrolling.
*/
private SlidingTabLayout mSlidingTabLayout;

/**
* A {@link ViewPager} which will be used in conjunction with the {@link SlidingTabLayout} above.
*/
private ViewPager mViewPager;

/**
* Inflates the {@link View} which will be displayed by this {@link Fragment}, from the app's
* resources.
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_sample, container, false);
}

// BEGIN_INCLUDE (fragment_onviewcreated)
/**
* This is called after the {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} has finished.
* Here we can pick out the {@link View}s we need to configure from the content view.
*
* We set the {@link ViewPager}'s adapter to be an instance of {@link SamplePagerAdapter}. The
* {@link SlidingTabLayout} is then given the {@link ViewPager} so that it can populate itself.
*
* @param view View created in {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}
*/
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
// BEGIN_INCLUDE (setup_viewpager)
// Get the ViewPager and set it's PagerAdapter so that it can display items
mViewPager = (ViewPager) view.findViewById(R.id.viewpager);
mViewPager.setAdapter(new CustomPagerAdapter(getFragmentManager(),getActivity()));
// END_INCLUDE (setup_viewpager)

// BEGIN_INCLUDE (setup_slidingtablayout)
// Give the SlidingTabLayout the ViewPager, this must be done AFTER the ViewPager has had
// it's PagerAdapter set.
mSlidingTabLayout = (SlidingTabLayout) view.findViewById(R.id.sliding_tabs);
mSlidingTabLayout.setViewPager(mViewPager);
// END_INCLUDE (setup_slidingtablayout)
}
// END_INCLUDE (fragment_onviewcreated)

public class CustomPagerAdapter extends FragmentPagerAdapter {

protected Context mContext;

public CustomPagerAdapter(FragmentManager fm, Context context) {
super(fm);
mContext = context;
}

@Override
public CharSequence getPageTitle(int position) {
return "Item " + (position + 1);
}

@Override
public Fragment getItem(int position) {

if(position==0){
// return fragment
}else{
ConversationsFragment fragment = new ConversationsFragment();
return fragment;
}
return null;
}

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

}
< /code>
И это мои разговорыфрагмент: < /p>
public class ConversationsFragment extends Fragment implements AbsListView.OnItemClickListener {

// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";

// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;

private OnFragmentInteractionListener mListener;

/**
* The fragment's ListView/GridView.
*/
private AbsListView mListView;

/**
* The Adapter which will be used to populate the ListView/GridView with
* Views.
*/
private List conversationsListItemList; // at the top of your fragment listW
private ListAdapter mAdapter;

// TODO: Rename and change types of parameters
public static ConversationsFragment newInstance(String param1, String param2) {
ConversationsFragment fragment = new ConversationsFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}

/**
* Mandatory empty constructor for the fragment manager to instantiate the
* fragment (e.g. upon screen orientation changes).
*/
public ConversationsFragment() {
}

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}

// TODO: Change Adapter to display your content
conversationsListItemList = new ArrayList();
conversationsListItemList.add(new ConversationsListItem("Example 1","conversa"));
conversationsListItemList.add(new ConversationsListItem("Example 2","conversa"));
conversationsListItemList.add(new ConversationsListItem("Example 3","conversa"));
mAdapter = new ConversationsListAdapter(getActivity(), conversationsListItemList);
/* mAdapter = new ArrayAdapter(getActivity(),
android.R.layout.simple_list_item_1, android.R.id.text1, DummyContent.ITEMS);*/
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_conversations, container, false);

// Set the adapter
mListView = (AbsListView) view.findViewById(android.R.id.list);
((AdapterView) mListView).setAdapter(mAdapter);

// Set OnItemClickListener so we can be notified on item clicks
mListView.setOnItemClickListener(this);

return view;
}

@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mListener = (OnFragmentInteractionListener) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString()
+ " must implement OnFragmentInteractionListener");
}
}

@Override
public void onDetach() {
super.onDetach();
mListener = null;
}

@Override
public void onItemClick(AdapterView parent, View view, int position, long id) {
if (null != mListener) {
// Notify the active callbacks interface (the activity, if the
// fragment is attached to one) that an item has been selected.
mListener.onFragmentInteraction(DummyContent.ITEMS.get(position).id);
}
}

public void setEmptyText(CharSequence emptyText) {
View emptyView = mListView.getEmptyView();

if (emptyView instanceof TextView) {
((TextView) emptyView).setText(emptyText);
}
}

public interface OnFragmentInteractionListener {
public void onFragmentInteraction(String id);
}

}
скриншоты:



Подробнее здесь: https://stackoverflow.com/questions/308 ... ntiateitem