Develop Reference

How to properly use ViewPager in android

I want to make a quiz application. So far I have 3 activities - home, quiz, score. Since the quiz activity contains multiple equivalent views ( image header, question and 4 answer buttons ), I did some reading and decided that
ViewPager with FragmentStatePagerAdapter show do the trick. So I made an xml template and inflated couple of test views and it was all looking good, until I started handling the user interaction.
I want to simulate a toggle button and there is only one correct answer to each question, so selecting one button should deselect the previous one ( if any ). When the button is pressed I change my Question model, then I find all 4 buttons with findViewById and reset their color filter. Then I set that filter back on my selected button. To determine which question model to update I use the current fragment position, which I have set ( using setTag, in fragment's onCreate ) in my template root view.
This is how I call my fragmets:
public Fragment getItem(int position) {
Question question = Repository.findById(position);
int correctAnswerBtnId;
switch (question.getCorrectAnswerIndex()) {
case 0: correctAnswerBtnId = R.id.quiz_answer_0_btn; break;
case 1: correctAnswerBtnId = R.id.quiz_answer_1_btn; break;
case 2: correctAnswerBtnId = R.id.quiz_answer_2_btn; break;
case 3: correctAnswerBtnId = R.id.quiz_answer_3_btn; break;
this.ACTIVITY_ROOT.setTag(question.getID());
Fragment fragment = new QuestionFragment();
Bundle args = new Bundle();
args.putSerializable(QuestionFragment.QUESTION, question);
fragment.setArguments(args);
return fragment;
}
My QuestionFragment onCreateView is as per documentation:
public View onCreateView(
LayoutInflater inflater,
ViewGroup container,
Bundle questionData) {
this.rootView = inflater.inflate(
R.layout.layout_question_template,
container,
false);
Bundle args = getArguments();
this.question = (Question) args.getSerializable(QuestionFragment.QUESTION);
populateInflatable();
rootView.findViewById(R.id.layout_question_template_root).setTag(this.question.getID());
return rootView;
}
In populateInflatable I use this.rootView to fintViewById and populate it with my question data. Then I change the color of a button, if there is selected one from the Question.
On button click I call selectAnserButton :
public void selectAnswerButton(View selectedButton) {
int questionId =
(int) this.activityRoot.findViewById(
R.id.layout_question_template_root).getTag(); //??
unSelectAllButtons();
changeColor(selectedButton);
Repository.findById(questionId).selectAnswer(selectedButton.getId());
}
Where unSelectAllButtons represents buttonToUnSelect.getBackground().clearColorFilter(); on the four buttons. and Repository is just a static class with example question data.
It all goes terribly wrong, when I have more then one view. On each fragment I inflate the same xml with same View IDs, as I have defined them. And as I now understand calling findViewById retrieves not one, but all views with that Id from my current, but also from my previous and next fragment as well. So every time I want to select my current fragment's view, I also modify the same view in the previous and next fragments as well. You can imagine how this is problematic. This makes me feel I have a fundamental mistake, because I don't think there is supposed to be more then one View with same ID.
I really don't understand how I should do this using ViewPager. At this point it feels like I'm trying to make a wood carving, but instead I am hacking the framework to pieces. There must be a better way to do this with ViewPager.
RESOLVED: Thanks to Soo Chun Jung for pointing me to the answer. In short what got it working for me was:
Passing my Question model id to each fragment with Bundle.
Storing each fragment in inside an ArrayMap with fragment position as key and fragment as value.
Getting each individual fragment from my selectAnswer function is now easy: first get the current fragment's position with myViewPager.getCurrentItem, then calling getter function which returns a fragment on the current position.
Now that I have the fragment I can easily change its button's because they are kept as private fields, assigned in the 'onCreateView` method.

Hope it's helpful~
adapter
class CustomAdapter extends FragmentPagerAdapter {
private final String[] TITLES = {"A", "B"};
private final String TAG = CustomAdapter.class.getSimpleName();
private final ArrayList<Fragment> mFragments;
private final FragmentManager fm;
public CustomAdapter(FragmentManager fm) {
super(fm);
mFragments = new ArrayList<>(getCount());
this.fm = fm;
}
#Override
public CharSequence getPageTitle(int position) {
return TITLES[position];
}
#Override
public int getCount() {
return TITLES.length;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
Log.d(TAG, "destroyItem position = " + position);
mFragments.remove(object);
super.destroyItem(container, position, object);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
Object object = super.instantiateItem(container, position);
mFragments.add((Fragment) object);
return object;
}
#Override
public Fragment getItem(int position) {
Log.d(TAG, "getItem position = " + position);
if (position == 0) {
return MyFragmentA.newInstance();
} else if (position == 1) {
return MyFragmentB.newInstance();
}
return null;
}
public MyFragmentA getMyFragmentA() {
synchronized (mFragments) {
for (Fragment f : mFragments) {
if (f instanceof MyFragmentA) {
return (MyFragmentA) f;
}
}
}
return null;
}
public MyFragmentB getMyFragmentB() {
synchronized (mFragments) {
for (Fragment f : mFragments) {
if (f instanceof MyFragmentB) {
return (MyFragmentB) f;
}
}
}
return null;
}
}
Fragment class
public class MyFragmentB extends Fragment {
...
public updateYourUI(){
//update something
}
}
Usage
mPager = (CustomViewPager) findViewById(R.id.pager);
mAdapter = new CustomAdapter(getChildFragmentManager());
mPager.setAdapter(mAdapter);
mAdapter.getMyFragmentB().updateYourUI();
for your comment below If you only have one kind Fragment. You can modify some function like this.
public static MyFragmentB newInstance(int ID) {
MyFragmentB fragment = new MyFragmentB();
Bundle bundle = new Bundle();
bundle.putInt("ID", ID);
fragment.setArguments(bundle);
return fragment;
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
myID = getArguments().getInt("ID");
....
}
public int getMyID() {
return myID;
}
public MyFragmentB getMyFragmentByID(String id) {
synchronized (mFragments) {
for (Fragment f : mFragments) {
if (f instanceof MyFragmentB) {
MyFragmentB temp = (MyFragmentB)f;
if(temp.getID.equals(id){
return (MyFragmentB) f;
}
}
}
}
return null;
}

Updating multiple lists of the same data at once with viewpager

I'm building an app that stores user entered expenses into an SQLite Database and displays them in a RecyclerView. My app currently has a view pager with 3 tabs. Each tab switches to a new fragment which pulls up expenses from the SQLite database that were from different time periods, specifically Today, This Week, and All which are displayed into a the RecyclerView. In each list, I can long press an item and delete it which will remove it from the SQLite database and from the current RecyclerView and update the list. Since it's possible that an item from one list will be in the others, I want to implement a way that I can check the lists in the other two fragments for which ever item is deleted and remove it from there was well but I'm having difficulty figuring out the best way to do this.
Now I could easily have the view pager recreate each fragment which would call the database again and create entirely new lists but this is inefficient. Does anyone have any ideas on how I can achieve this? Below is my current code:
ExpensePagerAdapter
class ExpensePagerAdapter extends FragmentPagerAdapter {
private String[] tabTitles = {getString(R.string.label_today),
getString(R.string.label_week), getString(R.string.label_all)};
ExpensePagerAdapter(FragmentManager fm){
super(fm);
}
#Override
public int getCount() {
return tabTitles.length;
}
#Override
public Fragment getItem(int position) {
return ExpenseListFragment.newInstance(position);
}
#Override
public CharSequence getPageTitle(int position) {
return tabTitles[position];
}
}
ExpenseListFragment
public class ExpenseListFragment extends Fragment{
private static final String LOG_TAG = "ExpenseListFragment";
private static final String ARG_TYPE = "viewType";
private RecyclerView rv;
private List<Expense> dayViewExpenses;
private List<LocalDate> weekViewDay;
private List<List<Expense>> weekViewExpenses;
private List<Expense> allExpenses;
public static ExpenseListFragment newInstance(int viewType){
Bundle bundle = new Bundle();
bundle.putInt(ARG_TYPE, viewType);
ExpenseListFragment f = new ExpenseListFragment();
f.setArguments(bundle);
return f;
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
Log.d(LOG_TAG, "onCreateView");
View v = inflater.inflate(R.layout.fragment_list, container, false);
rv = (RecyclerView) v.findViewById(R.id.rv_list);
rv.setLayoutManager(new LinearLayoutManager(getActivity()));
int viewType = getArguments().getInt(ARG_TYPE);
switch(viewType) {
case 0:
setupDayView();
break;
case 1:
setupWeekView();
break;
case 2:
setUpAllView();
break;
default:
}
return v;
}
private void setupDayView(){
dayViewExpenses = new ArrayList<>();
LocalDate currentDate = new LocalDate();
for (Expense e : ExpenseDb.getInstance(getActivity()).getAllExpenses()) {
if (currentDate.getMonthOfYear() == e.getMonth()
&& currentDate.getDayOfMonth() == e.getDay() && currentDate.getYear() == e.getYear()) {
dayViewExpenses.add(e);
}
}
rv.setAdapter(new ExpenseAdapter(getActivity(), dayViewExpenses));
}
private void setupWeekView(){
weekViewDay = new ArrayList<>();
weekViewExpenses = new ArrayList<>();
LocalDate weekStart = new LocalDate().withDayOfWeek(DateTimeConstants.MONDAY);
for (int i = 0; i < 7; i++) {
LocalDate dayOfWeek = weekStart.plusDays(i);
weekViewDay.add(dayOfWeek);
List<Expense> expensesForDay = new ArrayList<>();
for (Expense expense: ExpenseDb.getInstance(getActivity()).getAllExpenses()) {
if (expense.getDay() == dayOfWeek.getDayOfMonth() && expense.getMonth() == dayOfWeek.getMonthOfYear()
&& expense.getYear() == dayOfWeek.getYear()) {
expensesForDay.add(expense);
}
}
weekViewExpenses.add(expensesForDay);
}
rv.setAdapter(new WeekViewAdapter(getActivity(), weekViewDay, weekViewExpenses));
}
private void setUpAllView(){
allExpenses = ExpenseDb.getInstance(getActivity()).getAllExpenses();
rv.setAdapter(new ExpenseAdapter(getActivity(), allExpenses));
}
}
Any help would be great as I've been struggling to figure out an ideal way to accomplish this.

You can use event bus libraries (http://square.github.io/otto/) for this issue. You can't attach bus on ExpenseListFragments and send an object to that fragments at the same time. Recreating adapter is too cost for devices instead of.

Fragment State Pager Adapter Showing Wrong Fragment

I have a FragmentStatePagerAdapter which shows the details of current Fragment in the next Fragment. Here is the Page Adapter
public class CustomerPagerAdapter extends FragmentStatePagerAdapter
{
public SectionsPagerAdapter(FragmentManager fm)
{
super(fm);
}
#Override
public Fragment getItem(int position) {
Gson gson = new Gson();
Customer selectedCustomer = mCustomers.get(position);
String serializedCustomer = gson.toJson(selectedCustomer);
return CustomerDetailsFragment.newInstance(serializedCustomer);
}
#Override
public int getCount()
{
return mCustomers.size();
}
#Override
public CharSequence getPageTitle(int position)
{
Customer selectedCustomer = mCustomers.get(position);
String CustomerTitle = selectedCustomer.getFirstName() + " " + selectedCustomer.getLastName();
return CustomerTitle;
}
}
And here is the Fragment where the detail are displayed
public static class CustomerDetailsFragment extends Fragment {
private Customer passedInCustomer;
public CustomerDetailsFragment() {
// Required empty public constructor
}
public static CustomerDetailsFragment newInstance(String serializedCustomer){
CustomerDetailsFragment fragment = new CustomerDetailsFragment();
if (serializedCustomer != null && !serializedCustomer.isEmpty()){
Bundle args = new Bundle();
args.putString("customerInfo", serializedCustomer);
fragment.setArguments(args);
}
return fragment;
}
private void getPosition(){
Bundle args = getArguments();
if (args != null && args.containsKey("customerInfo")){
String serializedCustomer = (getArguments().getString("customerInfo"));
Gson gson = new Gson();
passedInCustomer = gson.fromJson(serializedCustomer, Customer.class);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
mRootView = inflater.inflate(R.layout.fragment_Customer_details, container, false);
if (passedInCustomer != null) {
showCustomerInfo();
}
return mRootView;
}
}
The problem stems from the fact that getItem is called twice for each swipe and the information that need to be displayed are contained in an List so when getItem is called twice the second object in the list is fetched and displayed in the screen where the first object was supposed to be displayed.
Has anyone dealt with displaying an nth number of items in a scrollable ViewPager where you have to create the Fragments on demand. If yes, can you give me suggestions how to deal with this.
Thanks

I notice that this problem is showing only when I have same fragments with diferent values ( what is probably in the most case ). So after long searching for right answer, i decided to in getItem() method every odd time return one fragment and every even time return another fragment ( These fragment are completely same, except their names:
#Override
public Fragment getItem(int position) {
if(position % 2 == 0){
return FragmentGalleryImage.newInstance(images.get(position), activity);
}else{
return FragmentGalleryImage2.newInstance(images.get(position), activity);
}
}
And i solved problem nice and smooth.

I solved the problem by calling on pager.getCurrentItem() to get the position of the currently displayed item.

Viewpager Adapter getItem always called for index 0 and 1

I was just wondering if it is the normal behaviour of viewpager and its adapter to always call the getItem() method for index 0 and 1, even if I immediately set a current position.
Here is my code:
mNewsPagerAdapter = new NewsDetailPagerAdapter(getChildFragmentManager());
mNewsPagerAdapter.updateNewsList(news);
mViewPager = (ViewPager) mView.findViewById(R.id.horizontal_view_pager);
mViewPager.setPageMargin(2);
mViewPager.setPageMarginDrawable(R.color.black);
mViewPager.setAdapter(mNewsPagerAdapter);
mViewPager.setCurrentItem(mCurrentPositionPager, false);
If I switch from my overview activity to my detail activity with this viewpager, the adapter always calls the getItem() method for position 0 and 1 and after that the getItem() method for the position of mOriginalPosition and its neighbors. I was wondering if this is the correct behaviour or if I missed something to implement it in a right way. Thanks for your help :)
Edit: Added my adapter code
public class NewsDetailPagerAdapter extends FragmentStatePagerAdapter {
private SparseArray<Fragment> mPageReferenceMap = new SparseArray<Fragment>();
private ArrayList<News> mNewsList;
public NewsDetailPagerAdapter(FragmentManager fm) {
super(fm);
}
/**
* Setzt die neuen News.
**/
public void updateNewsList(ArrayList<News> list) {
mNewsList = list;
}
#Override
public Fragment getItem(int position) {
Log.d("debug", "getItem position:" + position);
News newsItem = mNewsList.get(position);
NavigationFragment fragment = new NavigationFragment();
mPageReferenceMap.put(position, fragment);
return fragment;
}
#Override
public int getCount() {
return mNewsList.size();
}
#Override
public int getItemPosition(Object object) {
return POSITION_NONE;
}
public Fragment getFragment(int position) {
return mPageReferenceMap.get(position);
}
}

It is normal (and intelligent in my opinion).
ViewPager class has one property named mOffscreenPageLimit with default value of 1. This number determines how many pages on the left and on the right of the current page that the Viewpager will preload. For instance, you have 10 pages, current position is 5 and mOffcreenPageLimit is 1, the page at position 4 and 6 will be loaded.
You could change this property by calling this method
viewpager. setOffscreenPageLimit(int)
If you pass in an integer that is smaller than 1, it has no effect.

Yes, this is the normal behaviour of the ViewPager, because it will always try to stay ahead of the user by rendering tabs that limit with the drawing area. I personally don't recommend creating a custom ViewPager as you are almost sure to break functionality unless you really know what you are doing. Your adapter class should look something like this:
public class YourCustomPagerAdapter extends FragmentStatePagerAdapter {
private List<Fragment> fragmentList = new ArrayList<>();
private List<String> titleList = new ArrayList<>();
public WizardPagerAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment, String title) {
fragmentList.add(fragment);
titleList.add(title);
}
#Override
public Fragment getItem(int position) {
return fragmentList.get(position);
}
#Override
public CharSequence getPageTitle(int position) {
super.getPageTitle(position);
return titleList.get(position);
}
#Override
public int getCount() {
return fragmentList.size();
}
}
and you should add your fragments as such:
#Override
public void onCreate(Bundle savedInstanceState) {
...
YourCustomPagerAdapter adapter = new YourCustomPagerAdapter (getSupportFragmentManager());
adapter.addFragment(FragmentOne.newInstance(), "Frag 1");
adapter.addFragment(FragmentTwo.newInstance(), "Frag 2");
viewPager.setAdapter(adapter);
...
}

Actually this is the normale behavior. In fact, as soos as you associate the ViewPager with the adapter, the adapter creates the first visibile layout (index 0) end the next one (index 1). This is done by default in the "setAdapter". Then, when you set a different position, the adapter will instantiate the fragment at the selected index, the previous one and the next one.
This is the usual ViewPager setAdapter code:
public void setAdapter(PagerAdapter adapter) {
if (mAdapter != null) {
mAdapter.setViewPagerObserver(null);
mAdapter.startUpdate(this);
for (int i = 0; i < mItems.size(); i++) {
final ItemInfo ii = mItems.get(i);
mAdapter.destroyItem(this, ii.position, ii.object);
}
mAdapter.finishUpdate(this);
mItems.clear();
removeNonDecorViews();
mCurItem = 0;
scrollTo(0, 0);
}
final PagerAdapter oldAdapter = mAdapter;
mAdapter = adapter;
mExpectedAdapterCount = 0;
if (mAdapter != null) {
if (mObserver == null) {
mObserver = new PagerObserver();
}
mAdapter.setViewPagerObserver(mObserver);
mPopulatePending = false;
final boolean wasFirstLayout = mFirstLayout;
mFirstLayout = true;
mExpectedAdapterCount = mAdapter.getCount();
if (mRestoredCurItem >= 0) {
mAdapter.restoreState(mRestoredAdapterState, mRestoredClassLoader);
setCurrentItemInternal(mRestoredCurItem, false, true);
mRestoredCurItem = -1;
mRestoredAdapterState = null;
mRestoredClassLoader = null;
} else if (!wasFirstLayout) {
populate();
} else {
requestLayout();
}
}
if (mAdapterChangeListener != null && oldAdapter != adapter) {
mAdapterChangeListener.onAdapterChanged(oldAdapter, adapter);
}
}
In order to change the ViewPager behavior, you could extend the classic ViewPager overriding the setAdapter method and set the mCurrItem to the desired position.
I hope it helped
Edit:
After different tests, we found a solution.
If the ViewPager adapter is set after ViewPager layout become visible, items 0 and 1 are load.
If you want to avoid this behavior but you can't set the adapter before the layout become visible (because you are waiting for data), than you can use this workaround:
1) Set the ViewPager visibility initially to GONE
2) After you receive all the data, you update the adapter and you set the current item value
3) Finally you set the ViewPager visibility to VISIBLE
Here you can find an example:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.detail_overview_fragment, container, false);
final int position = getArguments().getInt("position");
final ViewPager viewPager = (ViewPager) v.findViewById(R.id.viewpager);
viewPager.setVisibility(View.GONE);
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
viewPager.setAdapter(new PagerAdapter(getChildFragmentManager()));
viewPager.setCurrentItem(position);
viewPager.setVisibility(View.VISIBLE);
}
},5000);
return v;
}

i think the error is the adapter:
/**
* Setzt die neuen News.
**/
public void updateNewsList(ArrayList<News> list) {
//mNewsList = list;
mNewsList.clear();
mNewsList.addAll(list);
/**
* Notifies the attached observers that the underlying data has been changed
* and any View reflecting the data set should refresh itself.
*/
this.notifyDataSetChanged();
}
error reason :this list is diffent entity for that adapter.

When creating two instances of the same fragment and registering them only the second one created gets event

I have created two fragments in a ViewPager , when I click on first one , Second fragment is taking the click.
This issue puts me in another position, when I create two instance from same fragment but with different data.
{
#Override
public Fragment getItem(int index) {
switch (index) {
case 1:
return FragmentBrandList.getInstance(tabs.getBrandList2(), 19,
title);
case 0:
return FragmentBrandList.getInstance(tabs.getBrandList1(), 19,
title);
}
return null;
}
#Override
public int getCount() {
return 2;
}
}
After creating ViewPager , both the fragments get created correctly , but when I click on any thing in the first fragment , the click event gets fired in second fragment not in the first fragment.
EDIT
public class TabsPagerAdapter extends FragmentPagerAdapter {
public TabsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
switch (index) {
case 1:
return FragmentBrandList.getInstance(tabs.getBrandList2(), 19,
title);
case 0:
return FragmentBrandList.getInstance(tabs.getBrandList1(), 19,
title);
}
return null;
}
#Override
public int getCount() {
return 2;
}
in FragmentBrandList
public class FragmentBrandList extends Fragment {
ArrayList<Brand> brandList = new ArrayList<Brand>();
int discoverID;
RecyclerView listView;
LinearLayoutManager mLayoutManager;
public static FragmentBrandList getInstance(ArrayList<Brand> brandList,
int discoverID, String title) {
FragmentBrandList frag = new FragmentBrandList();
Bundle b = new Bundle();
b.putSerializable("brandList", brandList);
b.putInt("discoverID", discoverID);
b.putString("title", title);
frag.setArguments(b);
return frag;
}
public FragmentBrandList() {
}
String title = "";
View v;
boolean isInflated = false;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (v == null) {
v = inflater.inflate(R.layout.fragment_list_view_brownbg,
container, false);
isInflated = true;
} else {
isInflated = false;
((ViewGroup) v.getParent()).removeView(v);
}
return v;
}
MainActivity activity;
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if (isInflated) {
activity = (MainActivity) getActivity();
initView();
}
}
public void initView(){
title = getArguments().getString("title");
discoverID = getArguments().getInt("discoverID");
listView = (RecyclerView) v.findViewById(R.id.listView);
mLayoutManager = new LinearLayoutManager(getActivity());
listView.setItemAnimator(new DefaultItemAnimator());
listView.setHasFixedSize(true);
listView.setLayoutManager(mLayoutManager);
listView.setAdapter(new BrandListRecAdapter(getActivity(),
R.layout.single_item_listview, brandList));
}
#Override
public void onResume() {
// handle on click
((BrandListRecAdapter) listView.getAdapter())
.setOnItemClickListener(new ItemClickListener() {
#Override
public void onItemClickListener(final int pos, View v) {
activity.replaceCurrentFragment(
FragmentBrandDetails.getInstance(
brandList.get(pos), "bank"), true,
true);
}}
EDIT
i think problem cause
when create second fragment , listview.onclick is overwrite first one !!
how can solve this peb?
EDIT
thank you to every one try to help me
problem is already because i use same adapter and same fragment
when second fragment created it is overwrite on item click
so when click in item is called second one !!!

Just put this android:clickable="true" in every fragment layout, and this will not happen again.

This is just an educated guess, but because a ViewPager will always create at least one extra Fragment on either side of the currently visible fragment, you may be creating two virtually identical Fragments in parallel, assigning them both onItemClickListeners in onResume and as such they are both responding to item clicks when an item is pressed on either Fragment.
You could try moving the onItemClickListener to the ViewHolder in your Adapter, rather assigning it in onResume. In addition, I wonder what a Brand object looks like in your RecyclerView, and whether it wouldn't be simpler to pass the current ViewPager page as a parameter in getInstance, and use this to access an Array containing the information necessary to fill your RecyclerView rows.
Here is a very brief example of how your ViewHolder may look:
class MyRecyclerViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener
public MyRecyclerViewHolder(View itemView) {
itemView.setOnClickListener(this);
//etc.