i wanted to make an app with a navigation drawer.
The problem is, that once i start the emulator i get a warning:
"Error:(63, 77) error: incompatible types: FaecherFragment cannot be converted to Fragment".
The error in the MainActivity says:
"Wrong 2nd argument type. found: ´com.example.android.test6.FaecherFragment´, required ´android.support.v4.app.Fragment´"
I already found some similar problems, which could all be solved by changing the import statements either from ´android.app.support.v4.app.Fragment´ to ´android.app.Fragment´ or the other way round...sadly that does not work for me...i literally tried each and every combination of both of these in each and every Fragment or class i have made, but it would not work.
I also tried to change my fragment so it extends ´android.support.v4.app.Fragment´...that does not work either.
I am new to android, so maybe it is just a beginners mistake...anyway, i really hope someone can help me!!
MainActivity:
package com.example.android.test6;
import android.app.Activity;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.DrawerLayout;
public class MainActivity extends AppCompatActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks, FaecherFragment.OnFragmentInteractionListener {
/**
* Fragment managing the behaviors, interactions and presentation of the navigation drawer.
*/
private NavigationDrawerFragment mNavigationDrawerFragment;
/**
* Used to store the last screen title. For use in {#link #restoreActionBar()}.
*/
private CharSequence mTitle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mNavigationDrawerFragment = (NavigationDrawerFragment)
getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
mTitle = getTitle();
// Set up the drawer.
mNavigationDrawerFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
}
#Override
public void onNavigationDrawerItemSelected(int position) {
// update the main content by replacing fragments
FragmentManager fragmentManager = getSupportFragmentManager();
switch (position) {
case 0:
fragmentManager.beginTransaction()
.replace(R.id.container, PlaceholderFragment.newInstance(position + 1))
.commit();
break;
case 1:
fragmentManager.beginTransaction()
.replace(R.id.container, PlaceholderFragment.newInstance(position + 1))
.commit();
break;
case 2:
fragmentManager.beginTransaction()
.replace(R.id.container, FaecherFragment.newInstance("a","b"))
.commit();
break;
}
}
public void onSectionAttached(int number) {
switch (number) {
case 1:
mTitle = getString(R.string.title_section1);
break;
case 2:
mTitle = getString(R.string.title_section2);
break;
case 3:
mTitle = getString(R.string.title_section3);
break;
}
}
public void restoreActionBar() {
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setTitle(mTitle);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.main, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onFragmentInteraction(String id) {
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
((MainActivity) activity).onSectionAttached(
getArguments().getInt(ARG_SECTION_NUMBER));
}
}
}
FaecherFragment:
package com.example.android.test6;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.app.ListFragment;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import java.util.ArrayList;
import java.util.List;
/**
* A fragment representing a list of Items.
* <p/>
* <p/>
* Activities containing this fragment MUST implement the {#linkOnFragmentInteractionListener}
* interface.
*/
public class FaecherFragment extends ListFragment {
// 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;
// TODO: Rename and change types of parameters
public static FaecherFragment newInstance(String param1, String param2) {
FaecherFragment fragment = new FaecherFragment();
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 FaecherFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
// TODO: replace hardcoded Faecher
List<Faecher> faecherList = new ArrayList<Faecher>();
faecherList.add(new Faecher("Mathe"));
faecherList.add(new Faecher("Englisch"));
faecherList.add(new Faecher("Sport"));
setListAdapter(new ArrayAdapter<Faecher>(getActivity(),
android.R.layout.simple_list_item_1, android.R.id.text1, faecherList));
}
#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 onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
//to start a new activity we have to declare an intent, this intent needs a context (the
//activity in which we are) and the class that we want to pass the intent into
Intent intent = new Intent(getActivity(), FaecherDetailsActivity.class);
//now we take the clicked listitem from our listView l and store it inside a variable
String title = l.getItemAtPosition(position).toString();
//we give this variable to the intent (as an extra)
intent.putExtra("value_title", title);
//now we start the activity
getActivity().startActivity(intent);
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);
}
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p/>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
public void onFragmentInteraction(String id);
}
}
You have
import android.app.ListFragment;
public class FaecherFragment extends ListFragment
Change import to support list fragment
You import wrong class. You must import fragment from support library:
import android.support.v4.app.ListFragment;
Your FaecherFragment extends ListFragment. And the ListFragment extends Fragment. This Fragment is incompatible with support.v4.app.FragmentManager.
So, you can make your FaecherFragment extend support.v4.app.ListFragment which extends support.v4.app.Fragment.
Related
I am trying to make an activity consisted of 4 fragments.
Each fragment gets replaced by another upon swiping (not destroying).
When I reach the 3rd fragment by swiping to left twice, the application terminates with error code saying
java.lang.IllegalStateException: Fragment already added: [4th fragment] {8e8204d #3 id=0x7f080033 android:switcher:2131230771:3}
But the problem is that I do not add any fragment after first onCreate called by the activity containing the fragments.
Could anyone give me an advice which directly I should take to resolve this issue?
Code for my main activity is as below.
import android.location.Location;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import java.util.ArrayList;
import java.util.List;
public class AnalysisActivity extends AppCompatActivity implements LocationFragment.OnFragmentInteractionListener, TypeFragment.OnFragmentInteractionListener, CountFragment.OnFragmentInteractionListener, SummaryFragment.OnFragmentInteractionListener {
/**
* The {#link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {#link FragmentPagerAdapter} derivative, which will keep every
* loaded fragment in memory. If this becomes too memory intensive, it
* may be best to switch to a
* {#link android.support.v4.app.FragmentStatePagerAdapter}.
*/
private SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {#link ViewPager} that will host the section contents.
*/
private ViewPager mViewPager;
private LocationFragment locationFragment;
private TypeFragment typeFragment;
private CountFragment countFragment;
private SummaryFragment summaryFragment;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_analysis);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Create the adapter that will return a fragment for each of the three
// primary sections of the activity.
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
locationFragment = new LocationFragment();
typeFragment = new TypeFragment();
countFragment = new CountFragment();
summaryFragment = new SummaryFragment();
mSectionsPagerAdapter.addFragment(locationFragment, "LocationFragment");
mSectionsPagerAdapter.addFragment(summaryFragment, "SummaryFragment");
mSectionsPagerAdapter.addFragment(typeFragment, "TypeFragment");
mSectionsPagerAdapter.addFragment(countFragment, "CountFragment");
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
getSupportFragmentManager().beginTransaction()
.replace(R.id.container, locationFragment)
.replace(R.id.container, summaryFragment)
.replace(R.id.container, typeFragment)
.replace(R.id.container, countFragment)
.commit();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_analysis, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
public PlaceholderFragment() {
}
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = null;
switch (getArguments().getInt(ARG_SECTION_NUMBER)) {
case 1:
rootView = inflater.inflate(R.layout.fragment_location, container, false);
break;
case 2:
rootView = inflater.inflate(R.layout.fragment_type, container, false);
break;
case 3:
rootView = inflater.inflate(R.layout.fragment_count, container, false);
break;
case 4:
rootView = inflater.inflate(R.layout.fragment_summary, container, false);
break;
}
return rootView;
}
}
#Override
public void onInputLocationSent(CharSequence input) {
summaryFragment.updateEditText_summary_location(input);
}
#Override
public void onInputTypeSent(CharSequence input) {
summaryFragment.updateEditText_summary_type(input);
}
#Override
public void onInputCountSent(CharSequence input) {
summaryFragment.updateEditText_summary_count(input);
}
#Override
public void onInputSummaryLocationSent(CharSequence input) {
}
#Override
public void onInputSummaryTypeSent(CharSequence input) {
}
#Override
public void onInputSummaryCountSent(CharSequence input) {
}
/**
* A {#link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
// return PlaceholderFragment.newInstance(position + 1);
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
}
}
Remove the following code. I am not sure what the intent is but it is probably the source of your problem.
getSupportFragmentManager().beginTransaction()
.replace(R.id.container, locationFragment)
.replace(R.id.container, summaryFragment)
.replace(R.id.container, typeFragment)
.replace(R.id.container, countFragment)
.commit();
The result of the above code is to replace R.id.container with locationFragment then summaryFragment then typeFragment and, finally, countFragment which is what R.id.container will actually contain at the end. As a result, when you swipe, the third swipe is to countFragment which was added by the above code so is a duplicate.
FragmentPagerAdapter will handle the fragments for you. You don't need to add them yourself.
So, I followed a tutorial to add a sliding navigation drawer to my app (plus did some tweaking of my own), but I'm a bit confused, possibly because I don't totally grok fragments. Basically I created an overflow menu with Log Out as the only option, so I could test my login system. I want that log out option in my navigation drawer so I can just get rid of that that overflow menu, but I can't figure out what to change so that it logs out instead of just displays the title of the fragment that was clicked on. And while I'm asking basically the same question, if I wanted to create the page that someone is viewing when they click on an option in the navigation drawer, where would I do that? In the respective fragment?
MainActivity.java
package me.paxana.alerta;
import android.app.Activity;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarDrawerToggle;
import android.app.Fragment;
import android.content.Intent;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MenuInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;
import com.parse.ParseUser;
import java.util.ArrayList;
import java.util.List;
import butterknife.Bind;
import butterknife.ButterKnife;
import me.paxana.alerta.adapter.SlidingMenuAdapter;
import me.paxana.alerta.fragment.Fragment1;
import me.paxana.alerta.fragment.Fragment2;
import me.paxana.alerta.fragment.Fragment3;
import me.paxana.alerta.model.ItemSlideMenu;
public class MainActivity extends AppCompatActivity {
public static final String TAG = MainActivity.class.getSimpleName();
private List<ItemSlideMenu> listSliding;
private SlidingMenuAdapter adapter;
private ListView listViewSliding;
private DrawerLayout drawerLayout;
private android.support.v7.app.ActionBarDrawerToggle actionBarDrawerToggle;
private Toolbar mToolbar;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.bind(this);
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser == null) {
navigateToLogin();
}
else {
Log.i(TAG, currentUser.getUsername());
}
listViewSliding = (ListView)findViewById(R.id.lv_sliding_menu);
drawerLayout = (DrawerLayout)findViewById(R.id.drawer_layout);
listSliding = new ArrayList<>();
//add item for sliding list
listSliding. add(new ItemSlideMenu(R.drawable.ic_action_settings, "Settings"));
listSliding.add(new ItemSlideMenu(R.drawable.ic_action_about, "About"));
listSliding.add(new ItemSlideMenu(R.drawable.ic_logout_black_48dp, "Log Out"));
adapter = new SlidingMenuAdapter(this, listSliding);
listViewSliding.setAdapter(adapter);
//display icon to open/close slider
mToolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(mToolbar);
assert getSupportActionBar() != null;
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
//set title
setTitle(listSliding.get(0).getTitle());
//item selected
listViewSliding.setItemChecked(0, true);
//close menu
drawerLayout.closeDrawer(listViewSliding);
//handle on item click
listViewSliding.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//set title
setTitle(listSliding.get(position).getTitle());
//item selected
listViewSliding.setItemChecked(position, true);
//close menu
drawerLayout.closeDrawer(listViewSliding);
}
});
actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.drawer_opened, R.string.drawer_closed) {
#Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
invalidateOptionsMenu();
}
#Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
invalidateOptionsMenu();
}
};
drawerLayout.setDrawerListener(actionBarDrawerToggle);
}
private void navigateToLogin() {
Intent intent = new Intent(this, LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if(actionBarDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
int itemId = item.getItemId();
if (itemId == R.id.action_logout) {
ParseUser.logOut();
navigateToLogin();
}
return super.onOptionsItemSelected(item);
}
#Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
actionBarDrawerToggle.syncState();
}
//create method replace fragment
private void replaceFragment(int pos) {
android.support.v4.app.Fragment fragment = null;
switch (pos) {
case 0:
fragment = new Fragment1();
break;
case 1:
fragment = new Fragment2();
break;
case 2:
fragment = new Fragment3();
break;
default:
fragment = new Fragment1();
break;
}
if(null != fragment) {
android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(R.id.main_content, fragment);
transaction.addToBackStack(null);
transaction.commit();
}
}
}
Fragment3 (I tried adding the logout option to this fragment but to no avail. Still what happens when I click it is the text "Log Out" displays on the screen)
package me.paxana.alerta.fragment;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.parse.ParseUser;
import me.paxana.alerta.LoginActivity;
import me.paxana.alerta.R;
/**
* A simple {#link Fragment} subclass.
* Activities that contain this fragment must implement the
* {#link Fragment3.OnFragmentInteractionListener} interface
* to handle interaction events.
* Use the {#link Fragment3#newInstance} factory method to
* create an instance of this fragment.
*/
public class Fragment3 extends Fragment {
// 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;
public Fragment3() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment Fragment3.
*/
// TODO: Rename and change types and number of parameters
public static Fragment3 newInstance(String param1, String param2) {
Fragment3 fragment = new Fragment3();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ParseUser.logOut();
Intent intent = new Intent(Fragment3.this.getActivity(), LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment3, container, false);
// Inflate the layout for this fragment
return rootView;
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p/>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
If I understood what you're looking for, you can log out by clicking the log-out element of the Navigation Drawer List:
Try this:
listViewSliding.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if (position == logOutIndex) { //You can do this if you know the position of the logOut button, e.g it's always at the end of the ListVIew
ParseUser.logOut();
navigateToLogin();
}
}
});
I hope that it works:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
if(actionBarDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
int itemId = item.getItemId();
if (itemId == R.id.action_logout) {
//ParseUser.logOut();
//navigateToLogin();
//If you the latest activity was te LoginActivity it goues to the LoginActivity
finish();
}
return super.onOptionsItemSelected(item);
}
Or if you is trying to do it from the drawer, replace you fragment3 by this:
private void replaceFragment(int pos) {
android.support.v4.app.Fragment fragment = null;
switch (pos) {
case 0:
fragment = new Fragment1();
break;
case 1:
fragment = new Fragment2();
break;
case 2:
//fragment = new Fragment3();
//If you the latest activity was te LoginActivity it goues to the LoginActivity
finish();
break;
default:
fragment = new Fragment1();
break;
}
Its hard to explain because you have to do so much to get it work.
The first idea I have is that you paste your code to log out into the switch case in the MainActivity.java:
private void replaceFragment(int pos) {
android.support.v4.app.Fragment fragment = null;
switch (pos) {
case 0:
fragment = new Fragment1();
break;
case 1:
fragment = new Fragment2();
break;
case 2:
ParseUser.logOut();
Intent intent = new Intent(Fragment3.this.getActivity(),LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
fragment = new Fragment3();
break;
default:
fragment = new Fragment1();
break;
}
if(null != fragment) {
android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(R.id.main_content, fragment);
...
I hope I understood you right but this has to fix the problem and if you now click on the 3rd fragment your logout has to be made.
If I am wrong write back soon and I will look for another solution ;)
So as you can see in the onCreate method i call getView on the 0th fragment in the "fragments" list. It returns null. I've tried putting a timer in the code and have it run every second and check if the view is null. And on the second tick of the timer the view is NOT null. Basically
MainActivity.java
package com.axinite.standapp;
import android.graphics.Color;
import android.os.CountDownTimer;
import android.os.Handler;
import android.support.annotation.Nullable;
import android.support.design.widget.TabLayout;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.widget.EditText;
import android.widget.NumberPicker;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import java.util.Vector;
public class MainActivity extends AppCompatActivity {
int i = 0;
/**
* The {#link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {#link FragmentPagerAdapter} derivative, which will keep every
* loaded fragment in memory. If this becomes too memory intensive, it
* may be best to switch to a
* {#link android.support.v4.app.FragmentStatePagerAdapter}.
*/
private SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {#link ViewPager} that will host the section contents.
*/
private ViewPager mViewPager;
int standUpSeconds = 4000;
List<android.support.v4.app.Fragment> fragments = new Vector<android.support.v4.app.Fragment>();
NumberPicker SUPickerH;
NumberPicker SUPickerM;
NumberPicker SUPickerS;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
fragments.add(Fragment.instantiate(this, BlankFragment.class.getName()));
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager(), fragments);
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
final TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
tabLayout.setSelectedTabIndicatorColor(Color.WHITE);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
final int[] ICONS = new int[] {
R.drawable.walking,
R.drawable.iris
};
for (int i=0; i < tabLayout.getTabCount(); i++)
{
tabLayout.getTabAt(i).setIcon(getDrawable(ICONS[i]));
}//endfor)
View view = ((BlankFragment) fragments.get(0)).getView();
if(view != null) {
TextView tv = (TextView) view.findViewById(R.id.glupost);
tv.setText("dasdas");
//Toast.makeText(getApplicationContext(), ((Fragment) fragments.get(0)).toString(), Toast.LENGTH_SHORT).show();
}
}
void Setup() {
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A {#link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
List<Fragment> fragments;
public SectionsPagerAdapter(FragmentManager fm, List<Fragment> fragments) {
super(fm);
this.fragments = fragments;
}
#Override
public Fragment getItem(int position) {
return fragments.get(position);
}
#Override
public int getCount() {
// Show 3 total pages.
return fragments.size();
}
#Override
public CharSequence getPageTitle(int position) {
return "";
}
}
}
BlankFragment.java
package com.axinite.standapp;
import android.app.Activity;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
/**
* A simple {#link Fragment} subclass.
* Activities that contain this fragment must implement the
* {#link BlankFragment.OnFragmentInteractionListener} interface
* to handle interaction events.
* Use the {#link BlankFragment#newInstance} factory method to
* create an instance of this fragment.
*/
public class BlankFragment extends Fragment {
protected View mView;
// 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;
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment BlankFragment.
*/
// TODO: Rename and change types and number of parameters
public static BlankFragment newInstance(String param1, String param2) {
BlankFragment fragment = new BlankFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
public BlankFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_blank, container, false);
mView = view;
return view;
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mListener = (OnFragmentInteractionListener) activity;
} catch (ClassCastException e) {
}
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p/>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
public void onFragmentInteraction(Uri uri);
}
}
The typical method for an Activity to communicate with its Fragments is as follows:
MyFragment frag = (MyFragment) getFragmentManager().findFragmentById(R.id.container_of_fragment);
frag.getMyTextView().setText("New text");
or (often preferred IMO)
MyFragment frag = (MyFragment) getFragmentManager().findFragmentByTag("fragment_tag_string_value");
frag.getMyTextView().setText("New text");
This is rendered more difficult with a ViewPager however, as the "id" of the container is the ViewPager itself, which contains multiple fragments. In addition, there isn't an in built adapter mechanism (that I'm aware of) to set tags to fragments.
There are two methods I can think of that circumvent this. First, you can use an EventBus, such as GreenRobot's EventBus, or LocalBroadcastManager from the Android API. GreenRobot's EventBus is also the recommended technique in the answer to this similar question.
An alternative would leverage the fact that a Fragment always has a reference to its host Activity, which means the Fragment could request the text from the Activity via an interface, which returns it to the Fragment:
public class MainActivity implements FragmentOne.Callbacks {
//...
#Override
public String requestTextViewString() {
return "Text to send to Fragment"
}
And inside your hypothetical FragmentOne:
public class FragmentOne extends Fragment {
private Callbacks mCallback;
private TextView mTextView;
public interface Callbacks {
String requestTextViewString();
}
#Override
public void onAttach(Activity activity) {
if (activity instanceof Callbacks) {
mCallback = (Callbacks) activity;
}
}
/*
*Later in your Fragment, when you want to get text from your MainActivity
* i.e. in onCreateView()
*/
mTextView.setText(mCallback.requestTextViewString());
Edit: Also keep in mind that attempting to access your Fragment from onCreate() in your Activity is likely to result in a NullPointerException. This diagram shows both lifecycles alongside each other. This shouldn't be a problem however, as anything required during the "set-up" lifecycle events of the Fragment can just be passed as an argument in the Fragment's newInstance() method:
public class FragmentOne extends Fragment {
private static final String KEY = "text_for_text_view_key";
public static FragmentOne newInstance(String textForTextView) {
Bundle args = new Bundle();
FragmentOne frag = new FragmentOne();
args.putString(KEY, textForTextView);
frag.setArguments(args);
return frag;
}
//And when required...
mTextView.setText(getArguments().getString(KEY));
I'm using Android Studio. I'm trying to develop an app where one fragment holds a list, and tapping an item displays another fragment with details. I built the list, following the tutorial available at: https://www.airpair.com/android/list-fragment-android-studio
I was planning on taking the code apart again after seeing how it ran. However, when I tried to run it (at step 6, where the basic list should be functioning), I got the error:
Error:(17, 21) error: no suitable method found for add(int,ExampleItemFragment)
method FragmentTransaction.add(Fragment,String) is not applicable
(argument mismatch; int cannot be converted to Fragment)
method FragmentTransaction.add(int,Fragment) is not applicable
(argument mismatch; ExampleItemFragment cannot be converted to Fragment)
in
package com.example.brittany.fragmentlistexample;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new ExampleItemFragment())
.commit();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Where & how should I implement this .add() method, or should I do something to the object I'm passing in order to make an inherited .add() accept it? The class ExampleItemFragment already extends Fragment.
ExampleItemFragment's code (mostly untouched from the default code):
package com.example.brittany.fragmentlistexample;
import android.app.Activity;
import android.os.Bundle;
import android.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.TextView;
import android.widget.Toast;
import com.example.brittany.fragmentlistexample.dummy.DummyContent;
import java.util.ArrayList;
import java.util.List;
public class ExampleItemFragment extends Fragment implements AbsListView.OnItemClickListener {
private List exampleListItemList; // at the top of your fragment list
// 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 ListAdapter mAdapter;
// TODO: Rename and change types of parameters
public static ExampleItemFragment newInstance(String param1, String param2) {
ExampleItemFragment fragment = new ExampleItemFragment();
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 ExampleItemFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
exampleListItemList = new ArrayList();
exampleListItemList.add(new ExampleListItem("Example 1"));
exampleListItemList.add(new ExampleListItem("Example 2"));
exampleListItemList.add(new ExampleListItem("Example 3"));
mAdapter = new ExampleListAdapter(getActivity(), exampleListItemList);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
// TODO: Change Adapter to display your content
mAdapter = new ArrayAdapter<DummyContent.DummyItem>(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_exampleitem, container, false);
// Set the adapter
mListView = (AbsListView) view.findViewById(android.R.id.list);
((AdapterView<ListAdapter>) 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) {
ExampleListItem item = (ExampleListItem)this.exampleListItemList.get(position);
Toast.makeText(getActivity(), item.getItemTitle() + " Clicked!"
, Toast.LENGTH_SHORT).show();
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);
}
}
/**
* The default content for this Fragment has a TextView that is shown when
* the list is empty. If you would like to change the text, call this method
* to supply the text it should use.
*/
public void setEmptyText(CharSequence emptyText) {
View emptyView = mListView.getEmptyView();
if (emptyView instanceof TextView) {
((TextView) emptyView).setText(emptyText);
}
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p/>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
public void onFragmentInteraction(String id);
}
}
You have to import the Fragment from the support library, not from the android.widget. Use import android.support.v4.app.Fragment; in your fragment.
I am using Android Studio 1.2.1.1 to learn Android programming. I created a new Project with Fragments and a BlankFragments-class.
But when I use the newInstance(String param1, String param2)-Method of the BlankFragment-Class in the MainActivity-Class, the compiler tells me android.support.v4.app.Fragment is required.
The problem is, the new BlankFragment-Class uses android.app.Fragment and the MainActivity uses android.support.v4.app.Fragment. But if I change the import in the MainActivity-Class I keep getting new Errors.
This is really frustrating, because these are the default structures in Android Studio as far as I know.
Main Activity:
package de.immozukunft.scouttools;
import java.util.Locale;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.FragmentPagerAdapter;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity implements ActionBar.TabListener {
/**
* The {#link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {#link FragmentPagerAdapter} derivative, which will keep every
* loaded fragment in memory. If this becomes too memory intensive, it
* may be best to switch to a
* {#link android.support.v4.app.FragmentStatePagerAdapter}.
*/
SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {#link ViewPager} that will host the section contents.
*/
ViewPager mViewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Set up the action bar.
final ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Create the adapter that will return a fragment for each of the three
// primary sections of the activity.
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
// When swiping between different sections, select the corresponding
// tab. We can also use ActionBar.Tab#select() to do this if we have
// a reference to the Tab.
mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
#Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
// For each of the sections in the app, add a tab to the action bar.
for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
// Create a tab with text corresponding to the page title defined by
// the adapter. Also specify this Activity object, which implements
// the TabListener interface, as the callback (listener) for when
// this tab is selected.
actionBar.addTab(
actionBar.newTab()
.setText(mSectionsPagerAdapter.getPageTitle(i))
.setTabListener(this));
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
// When the given tab is selected, switch to the corresponding page in
// the ViewPager.
mViewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}
#Override
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}
/**
* A {#link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
switch (position){
case 0:
return PlaceholderFragment.newInstance(position + 1);
break;
case 1:
return BlankFragment.newInstance("","");
break;
case 2:
return PlaceholderFragment.newInstance(position + 1);
break;
default:
return PlaceholderFragment.newInstance(position + 1);
}
}
#Override
public int getCount() {
// Show 3 total pages.
return 3;
}
#Override
public CharSequence getPageTitle(int position) {
Locale l = Locale.getDefault();
switch (position) {
case 0:
return getString(R.string.title_section1).toUpperCase(l);
case 1:
return getString(R.string.title_section2).toUpperCase(l);
case 2:
return getString(R.string.title_section3).toUpperCase(l);
}
return null;
}
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
}
BlankFragments:
package de.immozukunft.scouttools;
import android.app.Activity;
import android.net.Uri;
import android.os.Bundle;
import android.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
/**
* A simple {#link Fragment} subclass.
* Activities that contain this fragment must implement the
* {#link BlankFragment.OnFragmentInteractionListener} interface
* to handle interaction events.
* Use the {#link BlankFragment#newInstance} factory method to
* create an instance of this fragment.
*/
public class BlankFragment extends Fragment {
// 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;
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment BlankFragment.
*/
// TODO: Rename and change types and number of parameters
public static BlankFragment newInstance(String param1, String param2) {
BlankFragment fragment = new BlankFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
public BlankFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_blank, container, false);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
#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;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p/>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
public void onFragmentInteraction(Uri uri);
}
}
I can't just replace android.support.v4.app.Fragment with android.app.Fragment in the MainActivity
Yes, you can. Replace:
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.FragmentPagerAdapter;
with:
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.support.v13.app.FragmentPagerAdapter;
Note that the last line will require you to be depending upon support-v13 in your build.gradle file; if you have a dependency on support-v4 instead, replace that with support-v13.
You will also need to replace getSupportFragmentManager() with getFragmentManager() where it appears in your code. There may be a few other edits besides those, but that should get you close.
Here is sample project that uses native API Level 11+ fragments with a ViewPager.
But if I change the import in the MainActivity-Class I keep getting new Errors.
Never make a statement like that in a Stack Overflow question — or any support situation — without explaining what the errors are.