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我已经采取了一些例子ExpandableListFragment代码从这个网站的其他职务,并已通过我加载到一个片段从我的主要活动的XML文件中引用它:ExpandableListFragment中设置光标的位置是否扩展Fragment?

<?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="horizontal"> 

<fragment xmlns:android="http://schemas.android.com/apk/res/android" 
    android:name="salty.oaktreebrides.android.FAQ" 
    android:id="@+id/Fragment1" 
    android:layout_width="0px" 
    android:layout_weight="1" 
    android:layout_height="match_parent" /> 
</LinearLayout> 

但是我不能(新手)至确定我应该如何/在哪里设置光标以提供其中的数据。该代码目前正在启动,但正如我所期望的那样,我得到了Progress Circle Spinning,因为我没有提供任何数据。我有我自己的数据访问层类,它可以提供游标,只是不知道如何把所有的东西放在一起。我最终希望从片段API Demo中重新创建ExpandableList1.java功能,并让源代码为来自sqlite的游标。我希望这个代码能够满足这个要求。请帮忙。

import android.content.Context; 
import android.os.Bundle; 
import android.os.Handler; 
import android.support.v4.app.Fragment; 
import android.view.ContextMenu; 
import android.view.ContextMenu.ContextMenuInfo; 
import android.view.Gravity; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.View.OnCreateContextMenuListener; 
import android.view.ViewGroup; 
import android.view.animation.AnimationUtils; 
import android.widget.AdapterView; 
import android.widget.ExpandableListAdapter; 
import android.widget.ExpandableListView; 
import android.widget.FrameLayout; 
import android.widget.LinearLayout; 
import android.widget.ListAdapter; 
import android.widget.ProgressBar; 
import android.widget.TextView; 

public class ExpandableListFragment extends Fragment 
    implements OnCreateContextMenuListener, 
    ExpandableListView.OnChildClickListener, ExpandableListView.OnGroupCollapseListener, 
    ExpandableListView.OnGroupExpandListener 
    { 

    static final int INTERNAL_EMPTY_ID = 0x00ff0001; 
    static final int INTERNAL_PROGRESS_CONTAINER_ID = 0x00ff0002; 
    static final int INTERNAL_LIST_CONTAINER_ID = 0x00ff0003; 

    final private Handler mHandler = new Handler(); 

    final private Runnable mRequestFocus = new Runnable() { 
     public void run() { 
      mExpandableList.focusableViewAvailable(mExpandableList); 
     } 
    }; 

    final private AdapterView.OnItemClickListener mOnClickListener 
      = new AdapterView.OnItemClickListener() { 
     public void onItemClick(AdapterView<?> parent, View v, int position, long id) { 
      onListItemClick((ExpandableListView)parent, v, position, id); 
     } 
    }; 

    ExpandableListAdapter mAdapter; 
    ExpandableListView mExpandableList; 
    boolean mFinishedStart = false; 
    View mEmptyView; 
    TextView mStandardEmptyView; 
    View mProgressContainer; 
    View mExpandableListContainer; 
    CharSequence mEmptyText; 
    boolean mExpandableListShown; 

    public ExpandableListFragment() { 
    } 

    /** 
    * Provide default implementation to return a simple list view. Subclasses 
    * can override to replace with their own layout. If doing so, the 
    * returned view hierarchy <em>must</em> have a ListView whose id 
    * is {@link android.R.id#list android.R.id.list} and can optionally 
    * have a sibling view id {@link android.R.id#empty android.R.id.empty} 
    * that is to be shown when the list is empty. 
    * 
    * <p>If you are overriding this method with your own custom content, 
    * consider including the standard layout {@link android.R.layout#list_content} 
    * in your layout file, so that you continue to retain all of the standard 
    * behavior of ListFragment. In particular, this is currently the only 
    * way to have the built-in indeterminant progress state be shown. 
    */ 
    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     final Context context = getActivity(); 

     FrameLayout root = new FrameLayout(context); 

     // ------------------------------------------------------------------ 

     LinearLayout pframe = new LinearLayout(context); 
     pframe.setId(INTERNAL_PROGRESS_CONTAINER_ID); 
     pframe.setOrientation(LinearLayout.VERTICAL); 
     pframe.setVisibility(View.GONE); 
     pframe.setGravity(Gravity.CENTER); 

     ProgressBar progress = new ProgressBar(context, null, 
       android.R.attr.progressBarStyleLarge); 
     pframe.addView(progress, new FrameLayout.LayoutParams(
       ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)); 

     root.addView(pframe, new FrameLayout.LayoutParams(
       ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT)); 

     // ------------------------------------------------------------------ 

     FrameLayout lframe = new FrameLayout(context); 
     lframe.setId(INTERNAL_LIST_CONTAINER_ID); 

     TextView tv = new TextView(getActivity()); 
     tv.setId(INTERNAL_EMPTY_ID); 
     tv.setGravity(Gravity.CENTER); 
     lframe.addView(tv, new FrameLayout.LayoutParams(
       ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT)); 

     ExpandableListView lv = new ExpandableListView(getActivity()); 
     lv.setId(android.R.id.list); 
     lv.setDrawSelectorOnTop(false); 
     lframe.addView(lv, new FrameLayout.LayoutParams(
       ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT)); 

     root.addView(lframe, new FrameLayout.LayoutParams(
       ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT)); 

     // ------------------------------------------------------------------ 

     root.setLayoutParams(new FrameLayout.LayoutParams(
       ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT)); 

     return root; 
    } 

    /** 
    * Attach to list view once the view hierarchy has been created. 
    */ 
    @Override 
    public void onViewCreated(View view, Bundle savedInstanceState) { 
     super.onViewCreated(view, savedInstanceState); 
     ensureList(); 
    } 

    /** 
    * Detach from list view. 
    */ 
    @Override 
    public void onDestroyView() { 
     mHandler.removeCallbacks(mRequestFocus); 
     mExpandableList = null; 
     mExpandableListShown = false; 
     mEmptyView = mProgressContainer = mExpandableListContainer = null; 
     mStandardEmptyView = null; 
     super.onDestroyView(); 
    } 

    /** 
    * This method will be called when an item in the list is selected. 
    * Subclasses should override. Subclasses can call 
    * getListView().getItemAtPosition(position) if they need to access the 
    * data associated with the selected item. 
    * 
    * @param l The ListView where the click happened 
    * @param v The view that was clicked within the ListView 
    * @param position The position of the view in the list 
    * @param id The row id of the item that was clicked 
    */ 
    public void onListItemClick(ExpandableListView l, View v, int position, long id) { 
    } 

    /** 
    * Provide the cursor for the list view. 
    */ 
    public void setListAdapter(ExpandableListAdapter adapter) { 
     boolean hadAdapter = mAdapter != null; 
     mAdapter = adapter; 
     if (mExpandableList != null) { 
      mExpandableList.setAdapter(adapter); 
      if (!mExpandableListShown && !hadAdapter) { 
       // The list was hidden, and previously didn't have an 
       // adapter. It is now time to show it. 
       setListShown(true, getView().getWindowToken() != null); 
      } 
     } 
    } 

    /** 
    * Set the currently selected list item to the specified 
    * position with the adapter's data 
    * 
    * @param position 
    */ 
    public void setSelection(int position) { 
     ensureList(); 
     mExpandableList.setSelection(position); 
    } 

    /** 
    * Get the position of the currently selected list item. 
    */ 
    public int getSelectedItemPosition() { 
     ensureList(); 
     return mExpandableList.getSelectedItemPosition(); 
    } 

    /** 
    * Get the cursor row ID of the currently selected list item. 
    */ 
    public long getSelectedItemId() { 
     ensureList(); 
     return mExpandableList.getSelectedItemId(); 
    } 

    /** 
    * Get the activity's list view widget. 
    */ 
    public ExpandableListView getListView() { 
     ensureList(); 
     return mExpandableList; 
    } 

    /** 
    * The default content for a ListFragment has a TextView that can 
    * be shown when the list is empty. If you would like to have it 
    * shown, call this method to supply the text it should use. 
    */ 
    public void setEmptyText(CharSequence text) { 
     ensureList(); 
     if (mStandardEmptyView == null) { 
      throw new IllegalStateException("Can't be used with a custom content view"); 
     } 
     mStandardEmptyView.setText(text); 
     if (mEmptyText == null) { 
      mExpandableList.setEmptyView(mStandardEmptyView); 
     } 
     mEmptyText = text; 
    } 

    /** 
    * Control whether the list is being displayed. You can make it not 
    * displayed if you are waiting for the initial data to show in it. During 
    * this time an indeterminant progress indicator will be shown instead. 
    * 
    * <p>Applications do not normally need to use this themselves. The default 
    * behavior of ListFragment is to start with the list not being shown, only 
    * showing it once an adapter is given with {@link #setListAdapter(ListAdapter)}. 
    * If the list at that point had not been shown, when it does get shown 
    * it will be do without the user ever seeing the hidden state. 
    * 
    * @param shown If true, the list view is shown; if false, the progress 
    * indicator. The initial value is true. 
    */ 
    public void setListShown(boolean shown) { 
     setListShown(shown, true); 
    } 

    /** 
    * Like {@link #setListShown(boolean)}, but no animation is used when 
    * transitioning from the previous state. 
    */ 
    public void setListShownNoAnimation(boolean shown) { 
     setListShown(shown, false); 
    } 

    /** 
    * Control whether the list is being displayed. You can make it not 
    * displayed if you are waiting for the initial data to show in it. During 
    * this time an indeterminant progress indicator will be shown instead. 
    * 
    * @param shown If true, the list view is shown; if false, the progress 
    * indicator. The initial value is true. 
    * @param animate If true, an animation will be used to transition to the 
    * new state. 
    */ 
    private void setListShown(boolean shown, boolean animate) { 
     ensureList(); 
     if (mProgressContainer == null) { 
      throw new IllegalStateException("Can't be used with a custom content view"); 
     } 
     if (mExpandableListShown == shown) { 
      return; 
     } 
     mExpandableListShown = shown; 
     if (shown) { 
      if (animate) { 
       mProgressContainer.startAnimation(AnimationUtils.loadAnimation(
         getActivity(), android.R.anim.fade_out)); 
       mExpandableListContainer.startAnimation(AnimationUtils.loadAnimation(
         getActivity(), android.R.anim.fade_in)); 
      } else { 
       mProgressContainer.clearAnimation(); 
       mExpandableListContainer.clearAnimation(); 
      } 
      mProgressContainer.setVisibility(View.GONE); 
      mExpandableListContainer.setVisibility(View.VISIBLE); 
     } else { 
      if (animate) { 
       mProgressContainer.startAnimation(AnimationUtils.loadAnimation(
         getActivity(), android.R.anim.fade_in)); 
       mExpandableListContainer.startAnimation(AnimationUtils.loadAnimation(
         getActivity(), android.R.anim.fade_out)); 
      } else { 
       mProgressContainer.clearAnimation(); 
       mExpandableListContainer.clearAnimation(); 
      } 
      mProgressContainer.setVisibility(View.VISIBLE); 
      mExpandableListContainer.setVisibility(View.GONE); 
     } 
    } 

    /** 
    * Get the ListAdapter associated with this activity's ListView. 
    */ 
    public ExpandableListAdapter getListAdapter() { 
     return mAdapter; 
    } 

    private void ensureList() { 
     if (mExpandableList != null) { 
      return; 
     } 
     View root = getView(); 
     if (root == null) { 
      throw new IllegalStateException("Content view not yet created"); 
     } 
     if (root instanceof ExpandableListView) { 
      mExpandableList = (ExpandableListView)root; 
     } else { 
      mStandardEmptyView = (TextView)root.findViewById(INTERNAL_EMPTY_ID); 
      if (mStandardEmptyView == null) { 
       mEmptyView = root.findViewById(android.R.id.empty); 
      } else { 
       mStandardEmptyView.setVisibility(View.GONE); 
      } 
      mProgressContainer = root.findViewById(INTERNAL_PROGRESS_CONTAINER_ID); 
      mExpandableListContainer = root.findViewById(INTERNAL_LIST_CONTAINER_ID); 
      View rawExpandableListView = root.findViewById(android.R.id.list); 
      if (!(rawExpandableListView instanceof ExpandableListView)) { 
       if (rawExpandableListView == null) { 
        throw new RuntimeException(
          "Your content must have a ListView whose id attribute is " + 
          "'android.R.id.list'"); 
       } 
       throw new RuntimeException(
         "Content has view with id attribute 'android.R.id.list' " 
         + "that is not a ListView class"); 
      } 
      mExpandableList = (ExpandableListView)rawExpandableListView; 
      if (mEmptyView != null) { 
       mExpandableList.setEmptyView(mEmptyView); 
      } else if (mEmptyText != null) { 
       mStandardEmptyView.setText(mEmptyText); 
       mExpandableList.setEmptyView(mStandardEmptyView); 
      } 
     } 
     mExpandableListShown = true; 
     mExpandableList.setOnItemClickListener(mOnClickListener); 
     if (mAdapter != null) { 
      ExpandableListAdapter adapter = mAdapter; 
      mAdapter = null; 
      setListAdapter(adapter); 
     } else { 
      // We are starting without an adapter, so assume we won't 
      // have our data right away and start with the progress indicator. 
      if (mProgressContainer != null) { 
       setListShown(false, false); 
      } 
     } 
     mHandler.post(mRequestFocus); 
    } 

    /** 
    * Override this to populate the context menu when an item is long pressed. menuInfo 
    * will contain an {@link android.widget.ExpandableListView.ExpandableListContextMenuInfo} 
    * whose packedPosition is a packed position 
    * that should be used with {@link ExpandableListView#getPackedPositionType(long)} and 
    * the other similar methods. 
    * <p> 
    * {@inheritDoc} 
    */ 
    @Override 
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { 
    } 

    /** 
    * Override this for receiving callbacks when a child has been clicked. 
    * <p> 
    * {@inheritDoc} 
    */ 
    public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, 
      int childPosition, long id) { 
     return false; 
    } 

    /** 
    * Override this for receiving callbacks when a group has been collapsed. 
    */ 
    public void onGroupCollapse(int groupPosition) { 
    } 

    /** 
    * Override this for receiving callbacks when a group has been expanded. 
    */ 
    public void onGroupExpand(int groupPosition) { 
    } 

// /** 
//  * Ensures the expandable list view has been created before Activity restores all 
//  * of the view states. 
//  * 
//  *@see Activity#onRestoreInstanceState(Bundle) 
//  */ 
// @Override 
// protected void onRestoreInstanceState(Bundle state) { 
//  ensureList(); 
//  super.onRestoreInstanceState(state); 
// } 

    /** 
    * Updates the screen state (current list and other views) when the 
    * content changes. 
    * 
    * @see Activity#onContentChanged() 
    */ 

    public void onContentChanged() { 
//  super.onContentChanged(); 
     View emptyView = getView().findViewById(android.R.id.empty); 
     mExpandableList = (ExpandableListView)getView().findViewById(android.R.id.list); 
     if (mExpandableList == null) { 
      throw new RuntimeException(
        "Your content must have a ExpandableListView whose id attribute is " + 
        "'android.R.id.list'"); 
     } 
     if (emptyView != null) { 
      mExpandableList.setEmptyView(emptyView); 
     } 
     mExpandableList.setOnChildClickListener(this); 
     mExpandableList.setOnGroupExpandListener(this); 
     mExpandableList.setOnGroupCollapseListener(this); 

     if (mFinishedStart) { 
      setListAdapter(mAdapter); 
     } 
     mFinishedStart = true; 
    } 

    /** 
    * Get the activity's expandable list view widget. This can be used to get the selection, 
    * set the selection, and many other useful functions. 
    * 
    * @see ExpandableListView 
    */ 
    public ExpandableListView getExpandableListView() { 
     ensureList(); 
     return mExpandableList; 
    } 

    /** 
    * Get the ExpandableListAdapter associated with this activity's 
    * ExpandableListView. 
    */ 
    public ExpandableListAdapter getExpandableListAdapter() { 
     return mAdapter; 
    } 

    /** 
    * Gets the ID of the currently selected group or child. 
    * 
    * @return The ID of the currently selected group or child. 
    */ 
    public long getSelectedId() { 
     return mExpandableList.getSelectedId(); 
    } 

    /** 
    * Gets the position (in packed position representation) of the currently 
    * selected group or child. Use 
    * {@link ExpandableListView#getPackedPositionType}, 
    * {@link ExpandableListView#getPackedPositionGroup}, and 
    * {@link ExpandableListView#getPackedPositionChild} to unpack the returned 
    * packed position. 
    * 
    * @return A packed position representation containing the currently 
    *   selected group or child's position and type. 
    */ 
    public long getSelectedPosition() { 
     return mExpandableList.getSelectedPosition(); 
    } 

    /** 
    * Sets the selection to the specified child. If the child is in a collapsed 
    * group, the group will only be expanded and child subsequently selected if 
    * shouldExpandGroup is set to true, otherwise the method will return false. 
    * 
    * @param groupPosition The position of the group that contains the child. 
    * @param childPosition The position of the child within the group. 
    * @param shouldExpandGroup Whether the child's group should be expanded if 
    *   it is collapsed. 
    * @return Whether the selection was successfully set on the child. 
    */ 
    public boolean setSelectedChild(int groupPosition, int childPosition, boolean shouldExpandGroup) { 
     return mExpandableList.setSelectedChild(groupPosition, childPosition, shouldExpandGroup); 
    } 

    /** 
    * Sets the selection to the specified group. 
    * @param groupPosition The position of the group that should be selected. 
    */ 
    public void setSelectedGroup(int groupPosition) { 
     mExpandableList.setSelectedGroup(groupPosition); 
    } 
} 

回答

0

哇,你有什么似乎还挺庞大...

我不知道你的实现,但我通常设置适配器,我通常会为一个列表(的onCreate或onResume)。

下面是我如何做之前(使用修改SimpleCursorTreeAdapter):

public class EventListFragment extends Fragment { 

    private AttendanceDB mDbHelper; 
    public static Cursor mGroupsCursor; 
    private MyExpandableListAdapter mAdapter; 

    private String mGroup; 
    private String mChild; 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     View v = inflater.inflate(R.layout.explistfragment, container, false); 
     header = (TextView) v.findViewById(R.id.header1); 
     header.setText(R.string.event_header); 
     return v; 
    } 

    @Override 
    public void onActivityCreated(Bundle savedInstanceState) { 
     super.onActivityCreated(savedInstanceState); 
     mDbHelper = new AttendanceDB(getActivity()); 
     mDbHelper.open(); 
     fillData(mGroup, mChild); // Call to create and populate expandable list 
    } 

    private void fillData(String group, String child) { 
     ExpandableListView lv; 
     mGroupsCursor = mDbHelper.fetchGroup(group); 
     getActivity().startManagingCursor(mGroupsCursor); 
     mGroupsCursor.moveToFirst(); 
     lv = (ExpandableListView) getActivity().findViewById(R.id.explist); 
     lv.setItemsCanFocus(false); 
     lv.setChoiceMode(ExpandableListView.CHOICE_MODE_SINGLE);   

     mAdapter = new MyExpandableListAdapter(mGroupsCursor, getActivity(), 
       R.layout.explistlayout, 
       R.layout.explistlayout1, 
       new String[] { "_id" }, 
       new int[] { android.R.id.text1 }, 
       new String[] { child }, 
       new int[] { android.R.id.text1 }); 
     lv.setAdapter(mAdapter); 
     registerForContextMenu(lv); 

    public class MyExpandableListAdapter extends SimpleCursorTreeAdapter { 

     public MyExpandableListAdapter(Cursor cursor, Context context, 
       int groupLayout, int childLayout, String[] groupFrom, 
       int[] groupTo, String[] childrenFrom, int[] childrenTo) { 
      super(context, cursor, groupLayout, groupFrom, groupTo, 
        childLayout, childrenFrom, childrenTo); 
     } 
     @Override 
     protected Cursor getChildrenCursor(Cursor groupCursor) { 
      Cursor childCursor = mDbHelper.fetchChildren(mGroup, groupCursor 
        .getString(groupCursor 
          .getColumnIndex(AttendanceDB.EVENT_ROWID))); 
      getActivity().startManagingCursor(childCursor); 
      childCursor.moveToFirst(); 
      return childCursor; 
     } 
    } 
} 

希望这有助于!