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POMaking Array of Objects for ListView using ListFragment
 

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  1. POMaking Array of Objects for ListView using ListFragment
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    <p>I seem to be having troubles implementing a list of objects into a simple ListView.</p> <p>Here is my object class for each of the list elements. package com.example.android.fragments;</p> <pre><code>package com.example.android.fragments; public class ListObject { public String objectname; //name of schedule public boolean[] Days = { false, //monday false, //tuesday false, //and soforth false, false, false, false}; public int starthour, startminute, stophour, stopminute; //times from TimePicker public boolean vibrate; public ListObject() { objectname = null; //if doesnt work, do objectname = ""; vibrate = false; starthour = 8; startminute = 0; stophour = 15; stopminute = 0; } public ListObject(String name, boolean[] newdays, boolean vib, int a, int b, int c, int d) { objectname = name; Days = newdays; vibrate = vib; starthour = a; startminute = b; stophour = c; stopminute = d; } @Override public String toString() { String startampm = "am"; String stopampm = "am"; if (starthour &gt; 11) //turns into am/pm { startampm = "pm"; starthour -= 12; } if (stophour &gt; 11) //turns into am/pm { stopampm = "pm"; stophour -= 12; } String daysstring = null ; //initializes string representing days activated for(int i = 0; i &lt; 7; i++) //add into string the correct days { if (Days[i] == true) { if(i == 0) daysstring += "M, "; else if (i == 1) daysstring += "Tu, "; else if (i == 2) daysstring += "W, "; else if (i == 3) daysstring += "Th, "; else if (i == 4) daysstring += "F, "; else if (i == 5) daysstring += "Sa, "; else daysstring += "Su, "; } } daysstring = daysstring.substring(0, daysstring.length() - 3); //removes the last ', ' daysstring += ": "; String timestring = starthour + ":" + startminute + " " + startampm + " - " + stophour + ":" + stopminute + " " + stopampm; return objectname + "\n" + daysstring + timestring; } } </code></pre> <p>My main activity sets the layout to mainlayout which is a FrameLayout</p> <pre><code>package com.example.android.fragments; import android.os.Bundle; import android.support.v4.app.FragmentActivity; import android.support.v4.app.FragmentTransaction; public class MainActivity extends FragmentActivity implements MainListFragment.OnListSelectedListener { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.mainlayout); // Check whether the activity is using the layout version with // the fragment_container FrameLayout. If so, we must add the first fragment if (findViewById(R.id.fragment_container) != null) { //meaning, if using phone version // However, if we're being restored from a previous state, // then we don't need to do anything and should return or else // we could end up with overlapping fragments. if (savedInstanceState != null) { return; } // Create an instance of ExampleFragment MainListFragment firstFragment = new MainListFragment(); // In case this activity was started with special instructions from an Intent, // pass the Intent's extras to the fragment as arguments firstFragment.setArguments(getIntent().getExtras()); // Add the fragment to the 'fragment_container' FrameLayout getSupportFragmentManager().beginTransaction() .add(R.id.fragment_container, firstFragment).commit(); } } public void onArticleSelected(int position) { // Capture the article fragment from the activity layout InfoFragment articleFrag = (InfoFragment) getSupportFragmentManager().findFragmentById(R.id.article_fragment); //article_fragment exists in layout-large if (articleFrag != null) { // If article frag is available, we're in two-pane layout... // Call a method in the ArticleFragment to update its content articleFrag.updateArticleView(position); } else { // phone layout - swap frags // Create fragment and give it an argument for the selected article InfoFragment newFragment = new InfoFragment(); Bundle args = new Bundle(); args.putInt(InfoFragment.ARG_POSITION, position); newFragment.setArguments(args); FragmentTransaction transaction = getSupportFragmentManager().beginTransaction(); // Replace whatever is in the fragment_container view with this fragment, // and add the transaction to the back stack so the user can navigate back transaction.replace(R.id.fragment_container, newFragment); transaction.addToBackStack(null); // Commit the transaction transaction.commit(); } } } </code></pre> <p>Here is where the problem is, in my ListFragment here which is supposed to be open at the start of the application, I cannot simply create 3 of the objects and put them in the listview defined in my listlayout.xml which has the ListView id of mainlistview</p> <pre><code>package com.example.android.fragments; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.app.ListActivity; import android.os.Build; import android.os.Bundle; import android.support.v4.app.ListFragment; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView; public class MainListFragment extends ListFragment{ //used to extend ListActivity{ OnListSelectedListener mCallback; // The container Activity must implement this interface so the frag can deliver messages public interface OnListSelectedListener { /** Called by ListFragment when a list item is selected */ public void onArticleSelected(int position); } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // We need to use a different list item layout for devices older than Honeycomb int layout = Build.VERSION.SDK_INT &gt;= Build.VERSION_CODES.HONEYCOMB ? android.R.layout.simple_list_item_activated_1 : android.R.layout.simple_list_item_1; //using this now to add properties ListView mainlist = (ListView)getView().findViewById(R.id.mainlistview); //INFO FOR MADE UP OBJECTS boolean[] Days1 = { true, //monday false, //tuesday true, //and soforth false, true, false, false}; boolean[] Days2 = { false, //monday false, //tuesday false, //and soforth false, true, true, true}; boolean[] Days3 = { false, //monday false, //tuesday false, //and soforth true, false, false, false}; //create sample objects ListObject[] scheduleobjs = { new ListObject("Club Practice", Days1, true, 1, 0, 5, 25), new ListObject("Work", Days2, true, 3, 30, 14, 20), new ListObject("Church", Days3, true, 12, 5, 14, 20) }; // String[] liststring = // { // scheduleobjs[0].toString(), // scheduleobjs[1].toString(), // scheduleobjs[2].toString() // }; // ArrayList&lt;ListObject&gt; arraylist; //add objects to arraylist // arraylist.add(scheduleobjs[0]); // arraylist.add(scheduleobjs[1]); // arraylist.add(scheduleobjs[2]); String[] arraylist = new String[] { scheduleobjs[0].toString(), scheduleobjs[1].toString(), scheduleobjs[2].toString() }; ArrayAdapter&lt;String&gt; arrayadapter = new ArrayAdapter&lt;String&gt;(this, layout, arraylist); // setListAdapter(new ArrayAdapter&lt;String&gt;(getActivity(), layout, )) mainlist.setAdapter(arrayadapter); //inflate here??? } @Override public void onStart() { super.onStart(); // When in two-pane layout, set the listview to highlight the selected list item // (We do this during onStart because at the point the listview is available.) // if (getFragmentManager().findFragmentById(R.id.article_fragment) != null) { // getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE); COMMENTED OUT BECAUSE USED IN 2 PANE LAYOUT // } } @Override public void onAttach(Activity activity) { super.onAttach(activity); // This makes sure that the container activity has implemented // the callback interface. If not, it throws an exception. try { mCallback = (OnListSelectedListener) activity; } catch (ClassCastException e) { throw new ClassCastException(activity.toString() + " must implement OnListSelectedListener"); } } @Override public void onListItemClick(ListView l, View v, int position, long id) { // Notify the parent activity of selected item mCallback.onArticleSelected(position); // Set the item as checked to be highlighted when in two-pane layout getListView().setItemChecked(position, true); } } </code></pre> <p>You can see I have commented out previous attempts at doing this using the object classes' overridden toString(), where am I going wrong and what is the best way to implement this? I am wanting to eventually create a better listview since this only displays a string, and I want different sized and colored text with a checkbox for each object, but for now I am just trying to get this working.</p>
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    1. USAggieDev
    1. USAggieDev
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    1. COHave you tried implementing your own ArrayAdapter.
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      1. POMaking Array of Objects for ListView using ListFragment
      1. USNaveen
    2. COWhat exactly happens when you run your code? Does it crash? Does it show an empty/blank screen? From quickly looking at your ListFragment class you never override onCreateView to load your fragment layout.
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      1. POMaking Array of Objects for ListView using ListFragment
      1. USebarrenechea
 

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