/*
* Copyright 2013 wada811<at.wada811@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package at.wada811.app.fragment;
import android.content.Context;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.AnimationUtils;
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;
import at.wada811.android.library.R;
/**
* An fragment that displays an expandable list of items by binding to a data
* source implementing the ExpandableListAdapter, and exposes event handlers
* when the user selects an item.
*/
public class ExpandableListFragment extends Fragment implements ExpandableListView.OnGroupCollapseListener, ExpandableListView.OnGroupExpandListener, ExpandableListView.OnGroupClickListener, ExpandableListView.OnChildClickListener {
private static final int INTERNAL_EMPTY_ID = R.id.INTERNAL_EMPTY_ID;
private static final int INTERNAL_PROGRESS_CONTAINER_ID = R.id.INTERNAL_PROGRESS_CONTAINER_ID;
private static final int INTERNAL_LIST_CONTAINER_ID = R.id.INTERNAL_LIST_CONTAINER_ID;
private final Handler mHandler = new Handler();
private final Runnable mRequestFocus = new Runnable(){
@Override
public void run(){
mList.focusableViewAvailable(mList);
}
};
ExpandableListAdapter mAdapter;
ExpandableListView mList;
View mEmptyView;
TextView mStandardEmptyView;
View mProgressContainer;
View mListContainer;
CharSequence mEmptyText;
boolean mListShown;
public ExpandableListFragment() {
}
/**
* Provide default implementation to return a expandable list view. Subclasses
* can override to replace with their own layout. If doing so, the returned
* view hierarchy <em>must</em> have a ExpandableListView 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 ExpandableListFragment. In particular,
* this is currently the only way to have the built-in indeterminant progress state be shown.
*
* @param inflater The LayoutInflater object that can be used to inflate any views in the
* fragment,
* @param container If non-null, this is the parent view that the fragment's UI should be
* attached to. The fragment should not add the view itself, but this can be used to
* generate the LayoutParams of the view.
* @param savedInstanceState If non-null, this fragment is being re-constructed from a previous
* saved state as given here.
* @return Return the View for the fragment's UI, or null.
*/
@Override
public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState){
final Context context = getActivity();
final FrameLayout root = new FrameLayout(context);
// ------------------------------------------------------------------
final LinearLayout pframe = new LinearLayout(context);
pframe.setId(INTERNAL_PROGRESS_CONTAINER_ID);
pframe.setOrientation(LinearLayout.VERTICAL);
pframe.setVisibility(View.GONE);
pframe.setGravity(Gravity.CENTER);
final 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.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
// ------------------------------------------------------------------
final FrameLayout lframe = new FrameLayout(context);
lframe.setId(INTERNAL_LIST_CONTAINER_ID);
final TextView tv = new TextView(getActivity());
tv.setId(INTERNAL_EMPTY_ID);
tv.setGravity(Gravity.CENTER);
lframe.addView(tv, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
final ExpandableListView lv = new ExpandableListView(getActivity());
lv.setId(android.R.id.list);
lv.setDrawSelectorOnTop(false);
lframe.addView(lv, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
root.addView(lframe, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
// ------------------------------------------------------------------
root.setLayoutParams(new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
return root;
}
/**
* Attach to expandable list view once the view hierarchy has been created.
*
* @param view The View returned by {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}.
* @param savedInstanceState If non-null, this fragment is being re-constructed from a previous
* saved state as given here.
*/
@Override
public void onViewCreated(final View view, final Bundle savedInstanceState){
super.onViewCreated(view, savedInstanceState);
ensureList();
}
/**
* Detach from expandable list view.
*/
@Override
public void onDestroyView(){
mHandler.removeCallbacks(mRequestFocus);
mList = null;
mListShown = false;
mEmptyView = mProgressContainer = mListContainer = null;
mStandardEmptyView = null;
super.onDestroyView();
}
@Override
public boolean onGroupClick(final ExpandableListView parent, final View v, final int groupPosition, final long id){
return false;
}
/**
* Override this for receiving callbacks when a group has been expanded.
*
* @param groupPosition The group position that was expanded
*/
@Override
public void onGroupExpand(final int groupPosition){
if(Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO){
mList.setSelectedGroup(groupPosition);
}
}
/**
* Override this for receiving callbacks when a group has been collapsed.
*
* @param groupPosition The group position that was collapsed
*/
@Override
public void onGroupCollapse(final int groupPosition){
}
/**
* Override this for receiving callbacks when a child has been clicked.
* Callback method to be invoked when a child in this expandable list has been clicked.
*
* @param parent The ExpandableListView where the click happened
* @param v The view within the expandable list/ListView that was clicked
* @param groupPosition The group position that contains the child that was clicked
* @param childPosition The child position within the group
* @param id The row id of the child that was clicked
*/
@Override
public boolean onChildClick(final ExpandableListView parent, final View v, final int groupPosition, final int childPosition, final long id){
return false;
}
/**
* Provide the adapter for the expandable list.
*/
public void setListAdapter(final ExpandableListAdapter adapter){
final 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);
}
}
}
/**
* Sets the selection to the specified group.
*
* @param groupPosition The position of the group that should be selected.
*/
public void setSelectedGroup(final int groupPosition){
ensureList();
mList.setSelectedGroup(groupPosition);
}
/**
* 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(final int groupPosition, final int childPosition, final boolean shouldExpandGroup){
ensureList();
return mList.setSelectedChild(groupPosition, childPosition, shouldExpandGroup);
}
/**
* Gets the position (in packed position representation) of the currently selected group or
* child.
* Use getPackedPositionType(long), getPackedPositionGroup(long), and
* getPackedPositionChild(long) 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(){
ensureList();
return mList.getSelectedPosition();
}
/**
* Gets the ID of the currently selected group or child.
*
* @return The ID of the currently selected group or child.
*/
public long getSelectedId(){
ensureList();
return mList.getSelectedId();
}
/**
* Get the activity's expandable list view widget.
*/
public ExpandableListView getExpandableListView(){
ensureList();
return mList;
}
/**
* The default content for a ExpandableListFragment 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(final CharSequence text){
ensureList();
if(mStandardEmptyView == null){
throw new IllegalStateException("Can't be used with a custom content view");
}
mStandardEmptyView.setText(text);
if(mEmptyText == null){
mList.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(final boolean shown){
setListShown(shown, true);
}
/**
* Like {@link #setListShown(boolean)}, but no animation is used when transitioning from the
* previous state.
*/
public void setListShownNoAnimation(final 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(final boolean shown, final boolean animate){
ensureList();
if(mProgressContainer == null){
throw new IllegalStateException("Can't be used with a custom content view");
}
if(mListShown == shown){
return;
}
mListShown = shown;
if(shown){
if(animate){
mProgressContainer.startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_out));
mListContainer.startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_in));
}else{
mProgressContainer.clearAnimation();
mListContainer.clearAnimation();
}
mProgressContainer.setVisibility(View.GONE);
mListContainer.setVisibility(View.VISIBLE);
}else{
if(animate){
mProgressContainer.startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_in));
mListContainer.startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_out));
}else{
mProgressContainer.clearAnimation();
mListContainer.clearAnimation();
}
mProgressContainer.setVisibility(View.VISIBLE);
mListContainer.setVisibility(View.GONE);
}
}
/**
* Get the ExpandableListAdapter associated with this activity's ExpandableListView.
*/
public ExpandableListAdapter getExpandableListAdapter(){
return mAdapter;
}
private void ensureList(){
if(mList != null){
return;
}
final 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);
}else{
mStandardEmptyView.setVisibility(View.GONE);
}
mProgressContainer = root.findViewById(INTERNAL_PROGRESS_CONTAINER_ID);
mListContainer = root.findViewById(INTERNAL_LIST_CONTAINER_ID);
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);
}else if(mEmptyText != null){
mStandardEmptyView.setText(mEmptyText);
mList.setEmptyView(mStandardEmptyView);
}
}
mListShown = true;
// mList.setOnCreateContextMenuListener(this);
mList.setOnChildClickListener(this);
mList.setOnGroupCollapseListener(this);
mList.setOnGroupExpandListener(this);
mList.setOnGroupClickListener(this);
if(mAdapter != null){
final 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);
}
}