i have a viewPager that contains 3 tabs fragments.
the first and the second fragments works fine but when i sweep to the third tab
i do not see him.
the third tab has shown only when the activity with the viewPager has reload(move to another activity and return).
my code:
private void setupViewPager(ViewPager viewPager) {
adapter = new PagerAdapter(getSupportFragmentManager());
adapter.addFragment(new Fragment1(), Constants.TAB_0);
adapter.addFragment(new Fragment2(), Constants.TAB_1);
adapter.addFragment(new Fragment3(), Constants.TAB_2);
viewPager.setAdapter(adapter);
viewPager.setOffscreenPageLimit(3);
}
pager adapter:
public class PagerAdapter extends FragmentPagerAdapter {
/*
* Arraylist used to contain the fragments
* and contain fragments title's
*/
private final List<Fragment> fragmentList = new ArrayList<>();
private final List<String> fragmentTitleList = new ArrayList<>();
public PagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return fragmentList.get(position);
}
#Override
public int getCount() {
return fragmentList.size();
}
//Adds the fragment and it's title. Called in MainActivity
public void addFragment(Fragment fragment, String title) {
fragmentList.add(fragment);
fragmentTitleList.add(title);
}
//Retrieves the title of the tab
#Override
public CharSequence getPageTitle(int position) {
return fragmentTitleList.get(position);
}
#Override
public int getItemPosition(Object object) {
return POSITION_NONE;
}
}
Here is my adapter, on getItem I set the fragment object to the Fragment activity.
public class SectionPagerAdapter extends FragmentPagerAdapter {
Fragment fragment;
public SectionPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
if (position == 0){
fragment = new FragmentOne();
}
else if (position == 1){
fragment = new FragmentTwo();
}
else if (position == 2){
fragment = new FragmentThree();
}
return fragment;
}
#Override
public int getCount() {
return 3;
}
#Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "name one";
case 1:
return "name two";
case 2:
return "name three";
}
return null;
}
}
Then in my main activity I call it like so:
ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
SectionPagerAdapter sectionPagerAdapter = new SectionPagerAdapter(getSupportFragmentManager());
mViewPager.setAdapter(sectionPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
Try replacing your code with above and let me know if it helps!
USE new PagerAdapter(getChildSupportFragmentManager());instead of getSupportFragmentManager()
Try this one !!
Related
I have created two fragments in my app. I want to use these fragments in viewpager. This is my CustomAdapter for Viewpager:
public class CustomSwipeAdapter extends FragmentStatePagerAdapter {
public CustomSwipeAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
switch (position)
{
case 0:
return new fragmentComment();
case 1:
return new fragment_Rating();
default:
return new fragmentComment();
}
}
#Override
public int getCount() {
return 2;
}
}
And this is my Viewpager:
pager=(ViewPager)findViewById(R.id.view_pager);
FragmentActivity fm=new FragmentActivity();
CustomSwipeAdapter adapter=new CustomSwipeAdapter(fm.getSupportFragmentManager());
pager.setAdapter(adapter);
But when i run my app,nothing is shown in viewpager.
Can Anyone help?
You forgot
adapter.addFragment(new fragmentComment(), "FragmentComment");
adapter.addFragment(new fragment_Rating(), "FragmentRating");
Problem: I was modifying a small app where three tabs are there in fragment but all refers to text string. I wanted to use layout xml so that I can make good graphics in it. How can I do it in this code:
Information_tab refers to a string where I can put text, but I want a layout.
public class AdapterInformation extends FragmentPagerAdapter {
public AdapterInformation(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
Bundle bundle = new Bundle();
int imgResId = 0;
int tab = 0;
int colorResId = 0;
switch (index) {
case 0:
tab = R.string.information_tab1;
break;
case 1:
tab = R.string.information_tab2;
break;
case 2:
tab = R.string.information_tab3;
break;
}
bundle.putInt("image", imgResId);
bundle.putInt("tab",tab);
bundle.putInt("color", colorResId);
SwipeTabFragment swipeTabFragment = new SwipeTabFragment();
swipeTabFragment.setArguments(bundle);
return swipeTabFragment;
}
#Override
public int getCount() {
return 3;
}}
you can add fragment layout like this.
private void setupViewPager(final ViewPager viewPager) {
final ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
adapter.addFragment(new OneFragment(), "Pending Upload");
adapter.addFragment(new TwoFragment(), "Complete Upload");
viewPager.setAdapter(adapter);
}
and your fragmentPagerAdapter code is like this:
public class ViewPagerAdapter extends FragmentStatePagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager)
{
super(manager);
}
#Override
public int getItemPosition(Object object) {
return POSITION_NONE;
}
#Override
public Fragment getItem(int position)
{
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
and also add your setupViewPager method in onCreate()
viewPager = (ViewPager) findViewById(R.id.viewpager);
tabLayout = (TabLayout) findViewById(R.id.tabs);
setupViewPager(viewPager)
tabLayout.setupWithViewPager(viewPager);
Note: Do not use getItemPosition() method if its possible.. it
will produce redundancy of your listItems or ArrayList.. bcz every
time you swipe to other layout it will refresh page automatically..
its good if want this facility.. but you have write some code
regarding to handle this method.. and its also going to slow your
swipe animation if you have large amount of data.
For more information about tab layout and fragment: you can refer this one:
http://www.androidhive.info/2015/09/android-material-design-working-with-tabs/
I have a FragmentActivity with two Fragments in it and a sliding tab layout:
String titles[] = new String[] {"Tab One", "Tab Two"};
int numTabs = titles.length;
EventAdapter adapter = new EventAdapter(getSupportFragmentManager(), titles, numTabs);
ViewPager pager = (ViewPager) findViewById(R.id.pager);
pager.setAdapter(adapter);
SlidingTabLayout sliding_tabs = (SlidingTabLayout) findViewById(R.id.sliding_tabs);
sliding_tabs.setDistributeEvenly(true);
sliding_tabs.setViewPager(pager);
With the FragmentPagerAdapter:
private class EventAdapter extends FragmentPagerAdapter {
private List<String> titles;
private int numTabs;
public void addTab (String title) {
this.titles.add(title);
this.numTabs++;
this.notifyDataSetChanged();
}
public EventAdapter(FragmentManager fm, List<String> mTitles, int mNumTabs) {
super(fm);
this.titles = mTitles;
this.numTabs = mNumTabs;
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 2:
return new FragThree();
case 1:
return new FragTwo();
default:
return new FragOne();
}
}
#Override
public String getPageTitle(int position) {
return titles.get(position);
}
#Override
public int getCount() {
return numTabs;
}
}
Some time down the line, I would like to dynamically add the third tab to this layout. Is there a way to do this in code? As you can see, I already have the PagerAdapter set up to catch the third tab. I just need to load it in...
You need to add this method to your adapter EventAdapter :
public void addTab (String title) {
this.titles.add(title);
// this is the variable returned from getCount method
this.numbTabs++;
this.notifyDataSetChanged();
}
Main purpose is to add the tab and call notifydatasetchanged.
Now call addTab on this adapter's object and tab will be added.
after addTab do sliding_tab.setViewPager(this.pager);
Please accept if this solves the purpose.
My host activity has a viewpager with two fragments A and B.My activity code looks like this:
public class MainActivity extends AppCompatActivity implements
OnDataLoadedListener {
private ViewPager pager;
private MyPagerAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
pager = (ViewPager) findViewById(R.id.pager);
adapter = new MyPagerAdapter(getSupportFragmentManager());
pager.setAdapter(adapter);
final int pageMargin = (int) TypedValue.applyDimension(
TypedValue.COMPLEX_UNIT_DIP, 4, getResources()
.getDisplayMetrics());
pager.setPageMargin(pageMargin);
tabLayout.setupWithViewPager(pager);
}
public class MyPagerAdapter extends FragmentPagerAdapter {
private final String[] TITLES = { "A",
"B" };
public MyPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public CharSequence getPageTitle(int position) {
return TITLES[position];
}
#Override
public int getCount() {
return TITLES.length;
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return A.getInstance();
case 1:
return B.getInstance();
}
return null;
}
}
public Fragment findFragmentByPosition(int position) {
return getSupportFragmentManager().findFragmentByTag(
"android:switcher:" + pager.getId() + ":"
+ adapter.getItemId(position));
}
Now when activity start viewpager get populated with fragment properly and I try to access fragmentby using following code:
if (AFragment == null)
AFragment = (A) findFragmentByPosition(0);
if (BFragment == null)
BFragment = (B) findFragmentByPosition(1);
But AFragment and BFragment always contains null.I have read other simmilar question but it didn't help either.I need access to fragments as I want to call some methods defined in fragment from host activity.
Code to get an instance of fragment:
public static AFragment getInstance() {
AFragment fragment = new AFragment();
return fragment;
}
I'm think that the problem is that you need to move the method to the Adapter, because you need the original instance of the FragmentManager :
public class MyPagerAdapter extends FragmentPagerAdapter {
FragmentManager fm;
private final String[] TITLES = { "A",
"B" };
public MyPagerAdapter (FragmentManager fm) {
super(fm);
this.fm = fm;
}
#Override
public CharSequence getPageTitle(int position) {
return TITLES[position];
}
#Override
public int getCount() {
return TITLES.length;
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return A.getInstance();
case 1:
return B.getInstance();
}
return null;
}
public Fragment findFragmentByPosition(int position, int pagerId) {
return fm.findFragmentByTag(
"android:switcher:" + pagerId + ":"
+ getItemId(position));
}
}
So now you can call:
adapter.findFragmentByPosition(position, pager.getId());
I have a little problem
Current situation
I have a ViewPager with 2 Fragments inside.
viewPager = (ViewPager) findViewById(R.id.viewpager);
if (viewPager != null) {
setupViewPager(viewPager);
}
//////////////////////
private void setupViewPager(ViewPager viewPager) {
adapter = new PagerAdapter (getSupportFragmentManager());
adapter.addFragment(new Frag1(), "Frag1");
adapter.addFragment(new Frag2(), "Frag2");
viewPager.setAdapter(adapter);
}
And I put it in my TabLayout
tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
It works very well but now I want to change the fragments inside my tabs when I press a button in my navigation drawer.
Here :
private void setupDrawerContent(final NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
mDrawerLayout.closeDrawers();
menuItem.setChecked(true);
switch (menuItem.getItemId()) {
case R.id.nav_menu1:
break;
case R.id.nav_menu2:
here for example
break;
case R.id.nav_menu3:
break;
}
return true;
}
});
}
How should I do this?
PS: I tried to add some notifyDataSetChanged() for the adapter.. invalidate() the tabLayout ... I removed the code because I did it wrong.
Here is my PagerAdapter
static class PagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragments = new ArrayList<>();
private final List<String> mFragmentTitles = new ArrayList<>();
public PagerAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment, String title) {
mFragments.add(fragment);
mFragmentTitles.add(title);
}
#Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
#Override
public int getCount() {
return mFragments.size();
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitles.get(position);
}
}
Solved with FragmentStatePagerAdapter instead of FragmentPagerAdapter.