I want to have an information fragment on a sliding tab fragment, and be able to pass in some parameter to the information fragment when creating it. I've put (hopefully all) the relevant code below:
InfoFragment.java:
public class InfoFragment extends Fragment
{
private static final String HEADER_ARG = "HEADER";
private String header;
/**
* Use this factory method to create a new instance of this fragment using the provided parameters.
*/
public static InfoFragment newInstance(String header)
{
InfoFragment fragment = new InfoFragment ();
Bundle args = new Bundle();
args.putString(HEADER_ARG, header);
fragment.setArguments(args);
return fragment;
}
/**
* Required empty public constructor
*/
public InfoFragment() {}
/**
* Gets the args out of the bundle
*/
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
if (getArguments() != null)
{
this.header = getArguments().getString(HEADER_ARG);
}
else
{
Log.e("Frag", "Args = null");
}
}
// Rest of Fragment...
}
TabFragment.java:
public class TabFragment extends Fragment
{
/**
* Mandatory empty constructor for the fragment manager to instantiate the fragment (e.g. upon screen orientation changes).
*/
public TabFragment() {}
/**
* Create the Inventories tab view
*/
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.tab_2, container, false);
return view;
}
/**
* Dynamically add fragments
*/
#Override
public void onActivityCreated(Bundle savedInstanceState)
{
super.onActivityCreated(savedInstanceState);
InfoFragment infoFrag = InfoFragment.newInstance("MyHeader");
FragmentManager fm = getChildFragmentManager();
fm.beginTransaction().add(R.id.info_fragment, infoFrag);
}
// Rest of TabFragment...
}
tab_fragment.xml:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<fragment
android:id="#+id/character_item_fragment_1"
android:name="lomax.mycharacter3.InfoFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
The console log shows that the getArgs() = null, and I have no idea why. Any ideas?
Because you're using fragment tag, your fragment will be instantiated using empty constructor, also you forgot to call commit at the end on transaction, that's why you didn't get exception about view with missing id.
Fixed version:
tab_fragment.xml:
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/info_fragment"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
Code:
InfoFragment infoFrag = InfoFragment.newInstance("MyHeader");
FragmentManager fm = getChildFragmentManager();
fm.beginTransaction().add(R.id.info_fragment, infoFrag).commit();
Related
I have a working "folder explorer" for the internal storage only. But I want to improve that explorer to use internal and external storage. I want something like this:
Bellow is the basic code of my working folder explorer (internal storage only):
select_folders.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/listView"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.fragment.app.FragmentContainerView
android:id="#+id/fragmentContainer"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
SelectFoldersActiviy.java
public class SelectMusicFolderActivity extends AppCompatActivity {
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState == null) {
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragmentContainer, FoldersFragment.newInstance(path))
.commit();
}
}
...
}
The following fragment class uses a ListView to list all subfolders for a folder. In the onItemClick() method of the ListView objet I instantiate a new fragment with the current item path as argument. Like so:
FoldersFragment.java
public class FoldersFragment extends Fragment {
...
private static final String RUTA_KEY = "ruta";
private final String PATH = "ruta";
public static FoldersFragment newInstance(String ruta) {
FoldersFragment fragment = new FoldersFragment();
Bundle args = new Bundle();
args.putString(RUTA_KEY, ruta);
fragment.setArguments(args);
return fragment;
}
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
ruta = getArguments().getString(RUTA_KEY);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
...
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
getActivity().getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragmentContainer,
FoldersFragment.newInstance(currentItemPath))
.addToBackStack(null)
.commit();
}
}
}
With what I can combine the viewpager2 to get the aproach of the image?
I tried with fragmentcontainerview inside viewpager2, but viewpager2 dont support direct childs.
I tried with NavHostFragment too, but that needs a predefined navigation graph, and the number of folders is undetermined.
I have two fragments and a main activity. The first fragment, FriendsFragment (extends ListFragment) is displayed on the screen and when the user clicks an item, the main Activity replaces the FriendsFragment with FeedFragment, then calls a method from FeedFragment to update the textView.
I'm getting an error that the textView object in the FeedFragment class is null even though I instantiate using the findViewById method.
I have looked at related questions and have tried the solutions but nothing is working. I've tried doing getView().findViewById(R.id.feed_view), getActivity().findViewById(R.id.feed_view), and I've tried putting these in onActivityCreated() and onCreateView()
The only thing that worked is writing this code in onActivityCreated():
text = getView().findViewById(R.id.feed_view);
text.setText("some string");
but this is not what I want
FeedFragments.java
public class FeedFragment extends Fragment {
private static String TAG = "Feed Fragment";
private TextView text;
#Override
public void onActivityCreated(Bundle savedInstanceState) {
Log.i(TAG, "Entered FeedFragment.java onActivityCreated()");
super.onActivityCreated(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
Log.i(TAG, "Entered FeedFragment.java onCreateView()");
View v = inflater.inflate(R.layout.fragment_feed, container,false);;
text = v.findViewById(R.id.feed_view);
return v;
}
public void updateDisplay(int position)
{
Log.i(TAG, "FeedFragment.java: updateDisplay()");
text.setText(position);
}
MainActivity.java
// previously declared feedFragment: feedFragment = new FeedFragment();
public void onItemSelected(int position)
{
Log.i(TAG, "Entered onItemSelected(" + position + ")");
fragManager = getFragmentManager();
FragmentTransaction fragTransaction = fragManager.beginTransaction();
fragTransaction.replace(R.id.fragment_container, feedFragment, "feed_fragment");
fragTransaction.addToBackStack(null);
fragTransaction.commit();
feedFragment.updateDisplay(position);
}
fragment_feed.xml
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/feed_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/greeting" />
</ScrollView>
activity_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent" />
onViewcreated() is being called after updateDisplay() because the system doesn't run it right away.
you need to pass a value to the feedFragment on it's creation and store it in a bundle and retrieve it after the fragment internal code is run by the system.
the way you solve it is like this:
when you instantiate feedFragment you do it like this:
feedFragment = FeedFragment.newInstance(position)
and inside FeedFragment class you should have a static code:
private static final String ARG_PARAM1 = "param1";
public static FeedFragment newInstance(int param1) {
FeedFragment fragment = new FeedFragment();
Bundle args = new Bundle();
args.putInt(ARG_PARAM1, param1);
fragment.setArguments(args);
return fragment;
}
and non static code:
private int mParam1;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getInt(ARG_PARAM1);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
Log.i(TAG, "Entered FeedFragment.java onCreateView()");
View v = inflater.inflate(R.layout.fragment_feed, container,false);;
text = v.findViewById(R.id.feed_view);
text.setText(String.valueOf(mParam1));
return v;
}
I wrapped mParam1 in String.valueOf() because when you pass integer to setText it thinks you try to use a Strings.xml resource instead of the number you chose.
also I used very generic variable names. please change them to something meaningful so that your code makes sense.
I followed this question and tried my hand at calling a method which is in my Fragment. I'm trying to call the method from an activity. However it's not recognizing the fragment's method. Here's my code:
XML:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/peoplefragment">
<ListView
android:id="#+id/searchpeople_list"
android:layout_height="fill_parent"
android:layout_width="match_parent"
android:scrollbars="none"
android:background="#fff">
</ListView>
</RelativeLayout>
Fragment Code:
public class SearchPeopleTab extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View v = inflater.inflate(R.layout.activity_search_people_tab, container, false);
View rootView = inflater.inflate(R.layout.activity_search_people_tab, container, false);
return rootView;
}
public static void UpdateResults(String requestSearch)
{
new GetSearchResults(requestSearch).execute();
}
class GetSearchResults extends AsyncTask<Void, Void, Void> {
String requestSearch;
GetSearchResults(String searchtext)
{
this.requestSearch = searchtext;
}
#Override
protected Void doInBackground(Void... params) {
}
Activity Code: (Calling the Fragment's method)
private void PopulateResults() {
FragmentManager manager = (FragmentManager) getSupportFragmentManager();
Fragment fragment = manager.findFragmentById(R.id.peoplefragment);
fragment.UpdateResults(requestSearch); //thats the method in the fragment.
}
The 'UpdateResults()' part is underlined and the following message is given as an error:
Cannot resolve method UpdateResults()
Looks like it can't find the method. What am I doing wrong?
Remove the keyword static from the method.
And also, store the fragment in the SearchPeopleTab reference variable, that you created.
You don't really need the line to store the FragmentManager, you can directly use getSupportFragmentManager();
//FragmentManager fm = (FragmentManager) getSupportFragmentManager();
SearchPeopleTab fragment = (SearchPeopleTab) getSupportFragmentManager().findFragmentById(R.id.peoplefragment);
fragment.UpdateResults();
When static methods are used, they are called using the class name. When you want a method to be called on specific objects, the method should not be static.
You need to cast the Fragment to your defined class
private void PopulateResults() {
FragmentManager manager = (FragmentManager) getSupportFragmentManager();
SearchPeopleTab fragment = (SearchPeopleTab)manager.findFragmentById(R.id.peoplefragment);
fragment.UpdateResults(); //thats the method in the fragment.
}
I am trying to use the method
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a DummySectionFragment (defined as a static inner class
// below) with the page number as its lone argument.
Fragment fragment = new MappingPage();
Bundle args = new Bundle();
args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1);
fragment.setArguments(args);
return fragment;
}
I have written a class called MappingPage(), if I try to use the above method, the fragment I create is of type MappingPage because has been extended and hence throw an error as the function returns a fragment (not a MappingPage Object)
EDIT:I am getting an error when I do
Fragment fragment = new MappingPage();
Eclipse tell me that I need to change fragment to type MappingPage, which means i have to change the return type of the function
two Questions
1) How are you supposed to put your custom fragments into this?
2) Why does the dummySectionFrament return a Fragment Object and not a DummySectionFragment object?
thanks in advance
public static class DummySectionFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
public static final String ARG_SECTION_NUMBER = "section_number";
public DummySectionFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main_dummy,
container, false);
TextView dummyTextView = (TextView) rootView
.findViewById(R.id.section_label);
dummyTextView.setText(Integer.toString(getArguments().getInt(
ARG_SECTION_NUMBER)));
return rootView;
}
}
here is my class
public class MappingPage extends Fragment
{
private MapView map;
private MapController myMapController;
public static final String ARG_SECTION_NUMBER = "1";
public MappingPage() {
}
public View onCreateView (LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Context context = new ContextThemeWrapper(getActivity(), R.style.fragment_theme);
//LayoutInflater Inflater = inflater.cloneInContext(context);
View view=inflater.inflate(R.layout.fragment_main_dummy, container, false);
return view;
}
#Override
public void onResume() {
map = (MapView)getActivity().findViewById(R.id.openmapview);
map.setBuiltInZoomControls(true);
myMapController = map.getController();
myMapController.setZoom(15);
super.onResume();
}
}
Regarding your first question, this should work. MappingPage is an indirect instance of the Fragment class, and you can therefore return it.
About question two, the method that you call always returns a specific type, like Fragment in the case of getItem(). However, this can be a subclass of that as well, and if you are sure it is, you can safely cast it to that subclass.
I want to be able to display a button and after that button is clicked for the string typed to appear in a listview. I have that done, but i dont want that to apply to every tab. I just want it to display the send button and text box in a certain tab. I did some research and found that I may have to create a different fragment class for every tab, but I dont know how I am suppose to do that.
Java Code
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);
ListView list = (ListView)findViewById(R.id.messageList);
adapter = new MyAdapter(this);
list.setAdapter(adapter);
// Set up the action bar.
final ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Create the adapter that will return a fragment for each of the three
// primary sections of the app.
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));
}
}
private void newGame() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Developed by");
builder.setMessage("Shirwa Mohamed #Team_Shirwa");
builder.setPositiveButton( "ok", null);
builder.create().show();
}
#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 DummySectionFragment (defined as a static inner class
// below) with the page number as its lone argument.
Fragment fragment = new DummySectionFragment();
Bundle args = new Bundle();
args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1);
fragment.setArguments(args);
return fragment;
}
#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 dummy fragment representing a section of the app, but that simply
* displays dummy text.
*/
public static class DummySectionFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
public static final String ARG_SECTION_NUMBER = "section_number";
public DummySectionFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main_dummy, container, false);
TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
return rootView;
}
}
}
Activity XML :
<TabHost
android1:id="#android:id/tabhost"
android1:layout_width="match_parent"
android1:layout_height="match_parent"
android1:layout_alignParentLeft="true"
android1:layout_alignParentTop="true" >
<LinearLayout
android1:layout_width="match_parent"
android1:layout_height="match_parent"
android1:orientation="vertical" >
<TabWidget
android1:id="#android:id/tabs"
android1:layout_width="match_parent"
android1:layout_height="wrap_content" >
</TabWidget>
<FrameLayout
android1:id="#android:id/tabcontent"
android1:layout_width="match_parent"
android1:layout_height="match_parent" >
<LinearLayout
android1:id="#+id/tab1"
android1:layout_width="match_parent"
android1:layout_height="match_parent" >
</LinearLayout>
<LinearLayout
android1:id="#+id/tab2"
android1:layout_width="match_parent"
android1:layout_height="match_parent"
>
</LinearLayout>
<LinearLayout
android1:id="#+id/tab3"
android1:layout_width="match_parent"
android1:layout_height="match_parent" >
</LinearLayout>
</FrameLayout>
</LinearLayout>
</TabHost>
</RelativeLayout>
Fragment Class?
<TextView
android:id="#+id/section_label"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</RelativeLayout>
You are right, you need to create a fragment for each tab. Look at this link http://developer.android.com/guide/topics/ui/actionbar.html#Tabs it will help you understand how it works and how to implement it.