Databases
StackOverflow2013
Postsdbo
POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
    primarykey
    data
    text
    <p>I'm trying to save the expandablelistview child data to <a href="http://developer.android.com/reference/android/content/SharedPreferences.html" rel="nofollow noreferrer"><code>SharedPreferences</code></a>. The saving is working but when I try to load it then I get errors.</p> <p><strong>Problem:</strong></p> <p>When trying to load the settings and put it in a <a href="http://developer.android.com/reference/java/util/HashMap.html" rel="nofollow noreferrer">HashMap</a> I get these errors (shorted to 3 lines):</p> <pre><code>08-24 12:40:05.138: E/AndroidRuntime(807): FATAL EXCEPTION: main 08-24 12:40:05.138: E/AndroidRuntime(807): java.lang.ClassCastException: java.lang.String cannot be cast to com.example.expandablelistview.NewsItem 08-24 12:40:05.138: E/AndroidRuntime(807): at com.example.expandablelistview.ExpandableListAdapter.getChildView(ExpandableListAdapter.java:62) </code></pre> <p>For saving the data I'll use this code:</p> <pre><code> SharedPreferences pref = context.getSharedPreferences("myPrefs", MODE_PRIVATE); SharedPreferences.Editor editor= pref.edit(); for( Entry&lt;String, List&lt;NewsItem&gt;&gt; entry : listDataChild.entrySet() ) { editor.putString( entry.getKey(), String.valueOf(entry.getValue())); // Save the values of listDataChild } editor.commit(); </code></pre> <p>The output of the data is:</p> <pre><code>Yesterday: [[ headline=51.17346, 3.2252, Speed=2.10KM/H, Direction=158, date=18-8-2013 13:37:32]] Older: [[ headline=51.74346, 3.23252, Speed=2.00KM/H, Direction=122, date=17-8-2013 11:40:30]] Today: [[ headline=51.07346, 3.35252, Speed=0.00KM/H, Direction=122, date=19-8-2013 18:50:42]] </code></pre> <p>When trying to load these data (the errors happened here) and put it in a HashMap I'll use this (<a href="https://stackoverflow.com/questions/8151523/">from here</a>):</p> <pre><code> for( Entry&lt;String, ?&gt; entry : pref.getAll().entrySet() ) { listDataChild.put( entry.getKey(), (List&lt;NewsItem&gt;) Arrays.asList(entry.getValue()) ); // Put it in listDataChild } </code></pre> <p>The initialization of the data is happend here:</p> <pre><code>static void prepareListData(final Context context) { listDataHeader = new ArrayList&lt;String&gt;(); listDataChild = new HashMap&lt;String, List&lt;NewsItem&gt;&gt;(); // Adding child data listDataHeader.add("Today"); listDataHeader.add("Yesterday"); listDataHeader.add("Older"); List&lt;NewsItem&gt; today = new ArrayList&lt;NewsItem&gt;(); NewsItem newsData = new NewsItem(); newsData.setHeadline("51.07346, 3.35252"); newsData.setSpeed("0.00KM/H"); newsData.setDirection("122"); newsData.setDate("19-8-2013 18:50:42"); today.add(newsData); List&lt;NewsItem&gt; yesterday = new ArrayList&lt;NewsItem&gt;(); newsData = new NewsItem(); newsData.setHeadline("51.17346, 3.2252"); newsData.setSpeed("2.10KM/H"); newsData.setDirection("158"); newsData.setDate("18-8-2013 13:37:32"); yesterday.add(newsData); List&lt;NewsItem&gt; older = new ArrayList&lt;NewsItem&gt;(); newsData = new NewsItem(); newsData.setHeadline("51.74346, 3.23252"); newsData.setSpeed("2.00KM/H"); newsData.setDirection("122"); newsData.setDate("17-8-2013 11:40:30"); older.add(newsData); listDataChild.put(listDataHeader.get(0), today); listDataChild.put(listDataHeader.get(1), yesterday); listDataChild.put(listDataHeader.get(2), older); } </code></pre> <p><strong>Tried attempts:</strong></p> <p>I've tried to change the <code>listdataChild.put</code> to load the data to this:</p> <pre><code>listDataChild.put( entry.getKey(), new ArrayList&lt;NewsItem&gt;((Collection&lt;? extends NewsItem&gt;) Arrays.asList(entry.getValue())) ); </code></pre> <p>And to this:</p> <pre><code>listDataChild.put( entry.getKey(), (List&lt;NewsItem&gt;) new ArrayList(Arrays.asList(entry.getValue())) ); </code></pre> <p>But without any results. (I've got the same error)</p> <p><strong>Question:</strong></p> <p>Is it possible to convert the map values to list and put it in the HashMap <code>listDataChild</code>? </p> <p>Or should I use <code>newsData.setHeadline("Value");</code>, <code>newsData.setSpeed("Value");</code> etc.? (I don't know how to obtain specific values that's in <code>SharedPreferences</code> list)</p> <p><sup>(The source of <code>NewsItem.java</code> can be found <a href="http://pastebin.com/FcYHba51" rel="nofollow noreferrer">here</a>, the source of <code>ExpandableListAdapter.java</code> can be found <a href="http://pastebin.com/gGkZTkXX" rel="nofollow noreferrer">here</a>, and the source of <code>MainActivity.java</code> can be found <a href="http://pastebin.com/tXVJkfrL" rel="nofollow noreferrer">here</a>)</sup></p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USCommunity
    1. USuser1480019
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
      1. USuser1480019
      1. VTBountyStart
    3. VO
      singulars
      1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
      1. This table or related slice is empty.
      1. VTDownMod
    1. COI'm pretty sure the version of `ExpandableListAdapter` you've linked to *isn't* the one you're using, as the cast to `NewsItem` occurs on line 62, not 66 :(
      singulars
      1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
      1. USJon Skeet
    2. CO@JonSkeet Woops, I have deleted a few lines before upload. It's now indeed on line 62. Thanks for you notice. :)
      singulars
      1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
      1. USuser1480019
    3. COIt doesn't help that you haven't shown where you're initializing the `ExpandableListAdapter`, either...
      singulars
      1. POjava.lang.String cannot be cast to com.example.expandablelistview.NewsItem
      1. USJon Skeet
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload