I am working on android app and am trying to get fragments working but I've run into a problem.
When the app launches it loads an activity which is supposed to house the two fragments. Fragment1 contains a list of stored logins and fragment 2 will show the details associated with that login.
The list fragment is supposed to retrieve data from the SQLite database and display on the screen and once the item is clicked, it loads the second fragment, but I am having problem getting the first stage working.
In my main activity class I have the following.
public class PasswordListMain extends Activity {
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.password_management);
}
}
The password_management XML file contains the following
<?xml version="1.0" encoding="utf-8"?>
<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/passwordList"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.BoardiesITSolutions.PasswordManager.PasswordListFrag">
</fragment>
</LinearLayout>
It just contains the fragment as this is the portrait screen, I thought I'd get this bit working before getting it working side by side.
The PasswordListFrag contains the following
public class PasswordListFrag extends ListFragment{
Common common;
com.BoardiesITSolutions.logic.ManagePasswordList managePasswordList;
ArrayList<String> savedPassword;
TextView txtNoRecords;
ListView myListView;
ArrayAdapter<Spanned> passwordArrayAdapter;
AdView adView;
#Override
public View onCreateView(LayoutInflater inflator, ViewGroup container, Bundle savedInstanceState)
{
View view = inflator.inflate(R.layout.password_list, container, false);
myListView = getListView();
common = new Common(getActivity().getApplicationContext());
//AdView adView = (AdView)findViewById(R.id.adView);
common.requestAdvert(adView);
managePasswordList = new ManagePasswordList(getActivity().getApplicationContext());
//txtNoRecords = (TextView)findViewById(R.id.password_noRecords);
populateListArray();
common.showToastMessage("Adapter updated", Toast.LENGTH_LONG);
//myListView.setOnItemClickListener(mListView);
return view;
}
private void populateListArray()
{
ArrayList<Spanned> passwords = managePasswordList.getPasswordList();
if (passwords != null && passwords.size() > 0)
{
passwordArrayAdapter = new ArrayAdapter<Spanned>(getActivity().getApplicationContext(),
android.R.layout.simple_list_item_1, passwords);
setListAdapter(passwordArrayAdapter);
passwordArrayAdapter.setNotifyOnChange(true);
myListView.setTextFilterEnabled(true);
txtNoRecords.setVisibility(View.GONE);
}
else
{
txtNoRecords.setVisibility(View.VISIBLE);
}
}
}
Below is the XML for the list fragment
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView android:id="#+id/password_noRecords"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:layout_gravity="center"
android:text="There are currently\nno saved logins"
android:textSize="20dp"
android:textStyle="bold|italic"/>
<ListView
android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_above="#+id/adView">
</ListView>
<com.google.ads.AdView android:id="#+id/adView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
ads:adUnitId="5555555"
ads:adSize="BANNER"
android:layout_alignParentBottom="true">
</com.google.ads.AdView>
</RelativeLayout>
When the app loads it instantly crashes when it tries to load this screen.
The error is
java.lang.RuntimeException: Unable to start activity ComponentInfo
PasswordListMain: android.view.InflatException: Binary XML file line
#7 Error inflating class fragment
I have no idea what's causing this or how to fix the problem.
Thanks for any help you can provide.
My best guess for the issue is this line (but admittedly I'm unsure):
myListView = getListView();
You're calling it before the fragment has a view - and I don't think that will work too well. I would recommend doing your initialization work of the views involved in onActivityCreated() instead of in onCreateView() and the other components (like your data store thing and Common) in onCreate()
Related
I'm trying to develop a sign-up menu for a social app, that I'm working on. I would like the sign-up menu to consist of a PageViewer, which holds five fragments. The last three fragments contains a ListView, where the user can 'check' information about them selves. The XML is here:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:minWidth="25px"
android:minHeight="25px"
android:id="#+id/layoutSignupLists">
<TextView
android:text="Add something here"
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:id="#+id/signupListDescription" />
<ListView
android:id="#+id/interestListView"
android:layout_below="#id/signupListDescription"
android:layout_height="match_parent"
android:layout_width="match_parent" />
</RelativeLayout>
This layout is inflated, when the last three fragments are created as is displayed correctly. I have subscribed a delegate to the itemSelected event in the ListView as seen below:
public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
//Inflate view and find content
View view = inflater.Inflate(Resource.Layout.signupFragLayout4, container, false);
interestListView = view.FindViewById <ListView>(Resource.Id.interestListView);
var desc = view.FindViewById<TextView>(Resource.Id.signupListDescription);
//Adds the description
desc.Text = GetString(Resource.String.profile_menu_edit_interests);
//Populate ListView
interestListView.Adapter = new ArrayAdapter<string>(Activity,
Resource.Layout.CheckedListViewItem, MainActivity.InfoNames[(int)InfoType.Interest]);
interestListView.ChoiceMode = ChoiceMode.Multiple;
interestListView.ItemSelected += (object sender, AdapterView.ItemSelectedEventArgs e) =>
{
if(!Interests.Contains(e.Position))
Interests.Add(e.Position);
else
Interests.Remove(e.Position);
};
return view;
}
When putting a break-point in the delegate I find that it's never called and thus the ListView reset upon swiping right or left.
How can I make the fragment 'hold on' to the information so that it's displayed every time the fragment is shown?
Place the information in the MainActivity. You can make a simple reference to it by putting this variable in your fragment class:
MainActivity mainActivity;
And in your OnCreateView() place this to initialize it:
mainActivity = (MainActivity)Activity;
Now if you have any public variables in the mainActivity, you can reference them in the fragment like:
textView.Text = mainActivity.VariableName;
Additionally, for putting the information back in the fragment, override the 'OnResume' method like so:
public override void OnResume()
{
base.OnResume();
//Code to fill in all the information in your fragment again. I.E:
textView.Text = mainActivity.VariableName;
}
obviously not a profound question, but I think theres probably an error in my approach.
So I've added the file listview.xml to my project in the layout folder.
it contains this:
<?xml version="1.0" encoding="utf-8"?>
<ListView android:id="#+id/android:list"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android" />
I've also tried:
<?xml version="1.0" encoding="utf-8"?>
<ListView android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android" />
And i my main activity function generally looks like this:
public class ToDoManagerActivity extends ListActivity {
private static final int ADD_TODO_ITEM_REQUEST = 0;
private static final String FILE_NAME = "TodoManagerActivityData.txt";
private static final String TAG = "Lab-UserInterface";
// IDs for menu items
private static final int MENU_DELETE = Menu.FIRST;
private static final int MENU_DUMP = Menu.FIRST + 1;
ToDoListAdapter mAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Create a new TodoListAdapter for this ListActivity's ListView
mAdapter = new ToDoListAdapter(getApplicationContext());
// Put divider between ToDoItems and FooterView
getListView().setFooterDividersEnabled(true);
// TODO - Inflate footerView for footer_view.xml file
TextView footerView = (TextView) getLayoutInflater().inflate(R.layout.footer_view, null);
// NOTE: You can remove this block once you've implemented the assignment
if (null == footerView) {
return;
}
// TODO - Add footerView to ListView
getListView().addFooterView(footerView);
setListAdapter(mAdapter);
setContentView(R.layout.footer_view);
This keeps breaking with the error:
...java.lang.RunTimeException: content must have a ListView whose id attribute is 'android.R.id.list'
I noticed that if I comment out the setContentView(R.layout.footer_view) bit the error disappears, which is quite confusing as well, because it seems like the error should trigger before there.
This is confusing the hell out of me because as far as I can tell this element exists. Its seems like maybe I'm missing a step to load the ListView? I'm banging my head against the wall here and this seems like something really basic, and being a n00b sucks...So any help is much appreciated!
Cheers!
EDIT:
footer_view.xml contents:
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/footerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:text="#string/add_new_todo_item_string"
android:textSize="24sp" >
</TextView>
EDIT2:
Current onCreate after suggested edits:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Create a new TodoListAdapter for this ListActivity's ListView
mAdapter = new ToDoListAdapter(getApplicationContext());
// Put divider between ToDoItems and FooterView
getListView().setFooterDividersEnabled(true);
setListAdapter(mAdapter);
TextView footerView = (TextView) getLayoutInflater().inflate(R.layout.footer_view, getListView(), false);
getListView().addFooterView(footerView);
}
For an Activity that is extending ListActivity, the ListView needs to exist within the xml file that you are using in the activity, in your case that's the footer_view file.
Taken from the Google Dev Site - "ListActivity has a default layout that consists of a single, full-screen list in the center of the screen. However, if you desire, you can customize the screen layout by setting your own view layout with setContentView() in onCreate(). To do this, your own view MUST contain a ListView object with the id "#android:id/list""
To incorporate your footer below your list, try this:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<TextView
android:id="#+id/footerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:text="#string/add_new_todo_item_string"
android:textSize="24sp" >
</TextView>
</LinearLayout>
Here, try this in your layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/black"
android:id="#android:id/list" />
</LinearLayout>
That is exactly what I have in my app.
Then in your onCreate(), just this:
setContentView(R.layout.activity_main);
Try it and let me know if it works. That code should work. From there, we can continue on to isolate the problem.
EDIT:
Man, now I see your problem. Not a big deal here. Let's look at your code (edited to be shorter). The onCreate() method has this:
super.onCreate(savedInstanceState);
mAdapter = new ToDoListAdapter(getApplicationContext());
getListView().setFooterDividersEnabled(true);
TextView footerView = (TextView) getLayoutInflater().inflate(R.layout.footer_view, null);
getListView().addFooterView(footerView);
setListAdapter(mAdapter);
setContentView(R.layout.footer_view);
Do you see R.layout.activity_main anywhere there? There's your issue! Your R.layout.footer_view only contains a textview, it doesn't contain the ListView, and your Activity keeps looking for the ListView that you promised it that you'd have by extending a ListActivity.
Try this - change your onCreate() method to this:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mAdapter = new ToDoListAdapter(getApplicationContext());
setListAdapter(mAdapter);
}
Then your activity_main.xml layout file should look like this:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/black"
android:id="#android:id/list" />
</LinearLayout>
This should work. Let me know.
EDIT2:
Now add this to the end of your onCreate() method:
TextView footerView = (TextView) getLayoutInflater().inflate(R.layout.footer_view, null);
getListView().addFooterView(footerView);
Voila! Should work now.
I have a simple Android app. The layout folder shows an activity_main.xml file and a fragment_main.xml file. In that fragment.xml file I have placed a button that I've named buttonTest.
<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:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
tools:context="com.snapvest.thunderbird.app.MainActivity$PlaceholderFragment">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="TEST"
android:id="#+id/buttonTest"
android:layout_gravity="center_horizontal" />
</LinearLayout>
in the MainActivity.java file I'm trying to gain access to that buttonTest.
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
// Get access to the buttons
final Button buttonTest = (Button)findViewById(R.id.buttonTest);
}
It compiles just fine. But when I run it the buttonTest variable comes back as a null pointer.
Why is it not finding the buttonTest object?
I think I found the solution. MainActivity.java sets up the activity_main.xml which then uses fragment_main.xml as its (initially) single, primary fragment. That's why we are supposed to actually put all of our UI for the activity primarily in fragment_main.xml (and actually put NOTHING in activity_main.xml).
Near the bottom of MainActivity.java there is a section that initializes the fragment_main.xml. And it is THERE that I need to gain access to the buttons and other objects of the UI for the fragment. Such as:
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
// Get access to the buttons
final Button buttonAvailableOptions = (Button)rootView.findViewById(R.id.buttonAvailableOptions);
return rootView;
}
}
Most of that, above, is automatically added by Android Studio. The part starting with "Get access to the button" is mine and is where you set up any access to or processing of the buttons and other UI objects.
The reason why findViewById() is failing to find the button is because setContentView() primes findViewById() to only look in the layout.xml file you gave to setContentView(), and your button is not located in R.layout.activity_main. If your button is located in the Fragment (which it appears to be) then you should be accessing and manipulating it from the Fragment, not the Activity. This ensures that your Activity and Fragment logic stay decoupled, allowing you to re-use the Fragment with different Activities.
You can use like this.
final Button buttonAvailableOptions = getActivity().findViewById(R.id.buttonAvailableOptions);
I have a listview in my code and I want to set adapter on it.
But the issue is, even after initializing the listview, it is still null resulting into nullPointerException. (I checked it by logging and debugging)
I'm not able to access any view from that xml.
What am I missing? Any help appreciated.
xml
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:scrollbars="vertical" >
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<ListView
android:id="#+id/lvToday"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:divider="#FFF"
android:dividerHeight="2dp" />
<ListView
android:id="#+id/lvTomorrow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/lvToday"
android:divider="#FFF"
android:dividerHeight="2dp" />
</RelativeLayout>
</ScrollView>
Activity file
public class DashboardActivity extends Activity {
ListView lvToday, lvTomorrow;
TextView lblCall;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dashboard);
init();
}
private void init() {
lvToday = (ListView) findViewById(R.id.lvToday);
lvTomorrow = (ListView) findViewById(R.id.lvTomorrow);
TodayAppAdapter adapter = new TodayAppAdapter(DashboardActivity.this,
DashboardActivity.this);
// This line is giving NULL
lvToday.setAdapter(adapter);
TomorrowAppAdapter adapter1 = new TomorrowAppAdapter(
DashboardActivity.this, DashboardActivity.this);
// This line is giving NULL
lvTomorrow.setAdapter(adapter1);
}
}
1) test eclipse menu: Project -> Clean...
2) if you have more than one version for your xml layout (example layout-large, layout-xlarge,...), check if all of them have your view.
You are missing a TextView in your layout
Put a String []
along with name of your Adapter in your
OnDraw()
Method
For large screens I have two fragments, they shall be either top/bottom or left/right. The problem is that one fragment is taking (almost) all space is taking up by one fragment. For my activity I have two main.xml (one for portrait one for landscape). But they are basically similar (apart from orientation).
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" android:id="#+id/frag_cont" >
</LinearLayout>
In onCreate I add my fragments to that layout:
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
OverviewFragment of = new OverviewFragment();
FragmentTransaction tof = getFragmentManager().beginTransaction();
tof.add(R.id.frag_cont, of);
DetailFragmentInitial df = new DetailFragmentInitial();
tof.add(R.id.frag_cont, df);
tof.commit();
}
The two fragments look kind of similar in terms of onCreateView()
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
return inflater.inflate(R.layout.overview, container, false);
}
Finally the two xml files for these fragments look like this, first the smaller fragment:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" android:layout_weight="1">
<ImageView
android:id="#+id/imageLogo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/logo"
android:layout_centerInParent="true" />
<TextView
android:id="#+id/textB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="text"
android:layout_above="#id/imageLogo"
android:layout_centerHorizontal="true"/>
</RelativeLayout>
And now the greedy one taking the space:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:layout_weight="10000" >
<ListView
android:id="#+id/ListView01"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
I assumed that when I set both layout_weight to 1 then both will take the same amount of space, but even with the setting 1000:1 the bigger one takes about 2/3 of the space. Leaving the weight away will give the bigger fragment all the screen and the other one is not visiable at all. Any ideas?
Edit:
I followed the approach given below. Much better now in terms of space. On screen rotate the overview fragment (basically list view) is empty, the other fragment is still okay.
In OverviewFragment.java I repopulate the fragment in onActivityCreated():
public void onSaveInstanceState(Bundle bundle)
{
bundle.putSerializable("list", mList);
super.onSaveInstanceState(bundle);
}
#Override
public void onActivityCreated(Bundle savedInstanceState)
{
super.onActivityCreated(savedInstanceState);
if(savedInstanceState != null)
{
mList = (ArrayList<myObject>) savedInstanceState.getSerializable("list");
}
else
{
mAppList = new ArrayList<myObject>();
new getApps().execute();
}
ListView lv = (ListView) getActivity().findViewById(R.id.ListView01);
lv.setOnItemClickListener(new TableItemSelected());
mItemAdapter = new ItemAdapterOverview(getActivity().getApplicationContext(), mList);
lv.setAdapter(mItemAdapter);
}
when rotating the screen the onSaveInstanceState() is called first and then onActivityCreated() twice. The first call the saveInstanceState is not null, the second time it is. Anyway in both cases I should see my list, either build up from scratch or the saved list. Why isn't it and why is that method called twice?
Not entirely sure whether this will be causing your issue (I suspect it does), but using FragmentTransaction.add(..) doesn't add the Fragment into the container, it essentially replaces the container with that Fragment. The issue here is that you're adding both Fragments to the same container so they will take up the same space and cause issues.
A better way to do this would be to add two container views into your frag_cont LinearLayout (e.g. FrameLayouts), and give them two separate ids (e.g. frag_one and frag_two). Then in your onCreate(..), change it to read:
FragmentTransaction tof = getFragmentManager().beginTransaction();
tof.add(R.id.frag_one, of);
DetailFragmentInitial df = new DetailFragmentInitial();
tof.add(R.id.frag_two, df);
tof.commit();
This will make it so that the layout with id frag_one is filled by the OverviewFragment and the one with id frag_two replaced by the DetailFragmentInitial. You can then use the views in main.xml to tweak the sizes of the fragments as you see fit.