我想使我的ExpandableListActivity与Honeycomb兼容。
我想知道为什么兼容性包没有ExpandableListFragment。
有没有办法使ExpandableListView与普通的Fragment类一起使用？
如何使用LoaderManager加载游标？
最佳答案
我有同样的问题。我没有找到解决方案，因此我决定自己根据API级别8的android.support.v4.app.ListFragment(兼容API)和android.app.ExpandableListActivity来实现ExpandableListFragment。与API级别
不过，对于您有关游标和LoaderManager的问题，我没有答案。
关于我的ExpandableListFragment版本的一件事，您必须从封装 Activity 的oncontentchanged()-方法定义中自己调用其方法onContentChanged()，否则列表项将没有任何监听器。
ExpandableListFragment的源代码(在android.support.v4.app的本地包副本中，将其命名为您想要的名称):
package android.support.v4.app;
import android.app.Fragment;
import android.os.Bundle;
import android.os.Handler;
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.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
public class ExpandableListFragment extends Fragment
implements OnCreateContextMenuListener,
ExpandableListView.OnChildClickListener, ExpandableListView.OnGroupCollapseListener,
ExpandableListView.OnGroupExpandListener
{
static final int INTERNAL_EMPTY_ID = 0x00ff0001;
final private Handler mHandler = new Handler();
final private Runnable mRequestFocus = new Runnable() {
public void run() {
mList.focusableViewAvailable(mList);
}
};
final private AdapterView.OnItemClickListener mOnClickListener
= new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
onListItemClick((ListView)parent, v, position, id);
}
};
ExpandableListAdapter mAdapter;
ExpandableListView mList;
View mEmptyView;
TextView mStandardEmptyView;
View mListContainer;
boolean mSetEmptyText;
boolean mListShown;
boolean mFinishedStart = false;
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) {
FrameLayout root = new FrameLayout(getActivity());
TextView tv = new TextView(getActivity());
tv.setId(INTERNAL_EMPTY_ID);
tv.setGravity(Gravity.CENTER);
root.addView(tv, new FrameLayout.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT));
ListView lv = new ListView(getActivity());
lv.setId(android.R.id.list);
lv.setDrawSelectorOnTop(false);
root.addView(lv, new FrameLayout.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT));
ListView.LayoutParams lp = new ListView.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT);
root.setLayoutParams(lp);
return root;
}
/**
* Attach to list view once Fragment is ready to run.
*/
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
ensureList();
}
/**
* Detach from list view.
*/
@Override
public void onDestroyView() {
mHandler.removeCallbacks(mRequestFocus);
mList = 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(ListView 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 (mList != null) {
mList.setAdapter(adapter);
if (!mListShown && !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();
mList.setSelection(position);
}
public long getSelectedPosition() {
ensureList();
return mList.getSelectedPosition();
}
public long getSelectedId() {
ensureList();
return mList.getSelectedId();
}
public ExpandableListView getExpandableListView() {
ensureList();
return mList;
}
/**
* 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 (!mSetEmptyText) {
mList.setEmptyView(mStandardEmptyView);
mSetEmptyText = true;
}
}
/**
* 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 (mListShown == shown) {
return;
}
mListShown = shown;
if (shown) {
if (animate) {
mListContainer.startAnimation(AnimationUtils.loadAnimation(
getActivity(), android.R.anim.fade_in));
}
mListContainer.setVisibility(View.VISIBLE);
} else {
if (animate) {
mListContainer.startAnimation(AnimationUtils.loadAnimation(
getActivity(), android.R.anim.fade_out));
}
mListContainer.setVisibility(View.GONE);
}
}
/**
* Get the ListAdapter associated with this activity's ListView.
*/
public ExpandableListAdapter getExpandableListAdapter() {
return mAdapter;
}
private void ensureList() {
if (mList != null) {
return;
}
View root = getView();
if (root == null) {
throw new IllegalStateException("Content view not yet created");
}
if (root instanceof ExpandableListView) {
mList = (ExpandableListView)root;
} else {
mStandardEmptyView = (TextView)root.findViewById(INTERNAL_EMPTY_ID);
if (mStandardEmptyView == null) {
mEmptyView = root.findViewById(android.R.id.empty);
}
mListContainer = null; //root.findViewById(com.android.internal.R.id.listContainer);
View rawListView = root.findViewById(android.R.id.list);
if (!(rawListView instanceof ExpandableListView)) {
if (rawListView == null) {
throw new RuntimeException(
"Your content must have a ExpandableListView 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 ExpandableListView class");
}
mList = (ExpandableListView)rawListView;
if (mEmptyView != null) {
mList.setEmptyView(mEmptyView);
}
}
mListShown = true;
mList.setOnItemClickListener(mOnClickListener);
if (mAdapter != null) {
setListAdapter(mAdapter);
} else {
// We are starting without an adapter, so assume we won't
// have our data right away and start with the progress indicator.
setListShown(false, false);
}
mHandler.post(mRequestFocus);
}
@Override
public void onGroupExpand(int arg0) {
// TODO Auto-generated method stub
}
@Override
public void onGroupCollapse(int arg0) {
// TODO Auto-generated method stub
}
@Override
public boolean onChildClick(ExpandableListView arg0, View arg1, int arg2,
int arg3, long arg4) {
// TODO Auto-generated method stub
return false;
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
}
public void onContentChanged() {
View emptyView = getView().findViewById(android.R.id.empty);
mList = (ExpandableListView)getView().findViewById(android.R.id.list);
if (mList == null) {
throw new RuntimeException(
"Your content must have a ExpandableListView whose id attribute is " +
"'android.R.id.list'");
}
if (emptyView != null) {
mList.setEmptyView(emptyView);
}
mList.setOnChildClickListener(this);
mList.setOnGroupExpandListener(this);
mList.setOnGroupCollapseListener(this);
if (mFinishedStart) {
setListAdapter(mAdapter);
}
mFinishedStart = true;
}
}