/**
* Copyright 2012 Facebook
*
* 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 com.facebook.widget;
import android.content.Context;
import android.graphics.Bitmap;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewStub;
import android.widget.*;
import com.facebook.*;
import com.facebook.android.R;
import com.facebook.model.GraphObject;
import org.json.JSONObject;
import java.net.MalformedURLException;
import java.net.URL;
import java.text.Collator;
import java.util.*;
class GraphObjectAdapter<T extends GraphObject> extends BaseAdapter implements SectionIndexer {
private static final int DISPLAY_SECTIONS_THRESHOLD = 1;
private static final int HEADER_VIEW_TYPE = 0;
private static final int GRAPH_OBJECT_VIEW_TYPE = 1;
private static final int ACTIVITY_CIRCLE_VIEW_TYPE = 2;
private static final int MAX_PREFETCHED_PICTURES = 20;
private static final String ID = "id";
private static final String NAME = "name";
private static final String PICTURE = "picture";
private final Map<String, ImageRequest> pendingRequests = new HashMap<String, ImageRequest>();
private final LayoutInflater inflater;
private List<String> sectionKeys = new ArrayList<String>();
private Map<String, ArrayList<T>> graphObjectsBySection = new HashMap<String, ArrayList<T>>();
private Map<String, T> graphObjectsById = new HashMap<String, T>();
private boolean displaySections;
private List<String> sortFields;
private String groupByField;
private boolean showPicture;
private boolean showCheckbox;
private Filter<T> filter;
private DataNeededListener dataNeededListener;
private GraphObjectCursor<T> cursor;
private Context context;
private Map<String, ImageResponse> prefetchedPictureCache = new HashMap<String, ImageResponse>();
private ArrayList<String> prefetchedProfilePictureIds = new ArrayList<String>();
public interface DataNeededListener {
public void onDataNeeded();
}
public static class SectionAndItem<T extends GraphObject> {
public String sectionKey;
public T graphObject;
public enum Type {
GRAPH_OBJECT,
SECTION_HEADER,
ACTIVITY_CIRCLE
}
public SectionAndItem(String sectionKey, T graphObject) {
this.sectionKey = sectionKey;
this.graphObject = graphObject;
}
public Type getType() {
if (sectionKey == null) {
return Type.ACTIVITY_CIRCLE;
} else if (graphObject == null) {
return Type.SECTION_HEADER;
} else {
return Type.GRAPH_OBJECT;
}
}
}
interface Filter<T> {
boolean includeItem(T graphObject);
}
public GraphObjectAdapter(Context context) {
this.context = context;
this.inflater = LayoutInflater.from(context);
}
public List<String> getSortFields() {
return sortFields;
}
public void setSortFields(List<String> sortFields) {
this.sortFields = sortFields;
}
public String getGroupByField() {
return groupByField;
}
public void setGroupByField(String groupByField) {
this.groupByField = groupByField;
}
public boolean getShowPicture() {
return showPicture;
}
public void setShowPicture(boolean showPicture) {
this.showPicture = showPicture;
}
public boolean getShowCheckbox() {
return showCheckbox;
}
public void setShowCheckbox(boolean showCheckbox) {
this.showCheckbox = showCheckbox;
}
public DataNeededListener getDataNeededListener() {
return dataNeededListener;
}
public void setDataNeededListener(DataNeededListener dataNeededListener) {
this.dataNeededListener = dataNeededListener;
}
public GraphObjectCursor<T> getCursor() {
return cursor;
}
public boolean changeCursor(GraphObjectCursor<T> cursor) {
if (this.cursor == cursor) {
return false;
}
if (this.cursor != null) {
this.cursor.close();
}
this.cursor = cursor;
rebuildAndNotify();
return true;
}
public void rebuildAndNotify() {
rebuildSections();
notifyDataSetChanged();
}
public void prioritizeViewRange(int firstVisibleItem, int lastVisibleItem, int prefetchBuffer) {
if (lastVisibleItem < firstVisibleItem) {
return;
}
// We want to prioritize requests for items which are visible but do not have pictures
// loaded yet. We also want to pre-fetch pictures for items which are not yet visible
// but are within a buffer on either side of the visible items, on the assumption that
// they will be visible soon. For these latter items, we'll store the images in memory
// in the hopes we can immediately populate their image view when needed.
// Prioritize the requests in reverse order since each call to prioritizeRequest will just
// move it to the front of the queue. And we want the earliest ones in the range to be at
// the front of the queue, so all else being equal, the list will appear to populate from
// the top down.
for (int i = lastVisibleItem; i >= 0; i--) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(i);
if (sectionAndItem.graphObject != null) {
String id = getIdOfGraphObject(sectionAndItem.graphObject);
ImageRequest request = pendingRequests.get(id);
if (request != null) {
ImageDownloader.prioritizeRequest(request);
}
}
}
// For items which are not visible, but within the buffer on either side, we want to
// fetch those items and store them in a small in-memory cache of bitmaps.
int start = Math.max(0, firstVisibleItem - prefetchBuffer);
int end = Math.min(lastVisibleItem + prefetchBuffer, getCount() - 1);
ArrayList<T> graphObjectsToPrefetchPicturesFor = new ArrayList<T>();
// Add the IDs before and after the visible range.
for (int i = start; i < firstVisibleItem; ++i) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(i);
if (sectionAndItem.graphObject != null) {
graphObjectsToPrefetchPicturesFor.add(sectionAndItem.graphObject);
}
}
for (int i = lastVisibleItem + 1; i <= end; ++i) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(i);
if (sectionAndItem.graphObject != null) {
graphObjectsToPrefetchPicturesFor.add(sectionAndItem.graphObject);
}
}
for (T graphObject : graphObjectsToPrefetchPicturesFor) {
URL url = getPictureUrlOfGraphObject(graphObject);
final String id = getIdOfGraphObject(graphObject);
// This URL already have been requested for pre-fetching, but we want to act in an LRU manner, so move
// it to the end of the list regardless.
boolean alreadyPrefetching = prefetchedProfilePictureIds.remove(id);
prefetchedProfilePictureIds.add(id);
// If we've already requested it for pre-fetching, no need to do so again.
if (!alreadyPrefetching) {
downloadProfilePicture(id, url, null);
}
}
}
protected String getSectionKeyOfGraphObject(T graphObject) {
String result = null;
if (groupByField != null) {
result = (String) graphObject.getProperty(groupByField);
if (result != null && result.length() > 0) {
result = result.substring(0, 1).toUpperCase();
}
}
return (result != null) ? result : "";
}
protected CharSequence getTitleOfGraphObject(T graphObject) {
return (String) graphObject.getProperty(NAME);
}
protected CharSequence getSubTitleOfGraphObject(T graphObject) {
return null;
}
protected URL getPictureUrlOfGraphObject(T graphObject) {
String url = null;
Object o = graphObject.getProperty(PICTURE);
if (o instanceof String) {
url = (String) o;
} else if (o instanceof JSONObject) {
ItemPicture itemPicture = GraphObject.Factory.create((JSONObject) o).cast(ItemPicture.class);
ItemPictureData data = itemPicture.getData();
if (data != null) {
url = data.getUrl();
}
}
if (url != null) {
try {
return new URL(url);
} catch (MalformedURLException e) {
}
}
return null;
}
protected View getSectionHeaderView(String sectionHeader, View convertView, ViewGroup parent) {
TextView result = (TextView) convertView;
if (result == null) {
result = (TextView) inflater.inflate(R.layout.com_facebook_picker_list_section_header, null);
}
result.setText(sectionHeader);
return result;
}
protected View getGraphObjectView(T graphObject, View convertView, ViewGroup parent) {
View result = convertView;
if (result == null) {
result = createGraphObjectView(graphObject, convertView);
}
populateGraphObjectView(result, graphObject);
return result;
}
private View getActivityCircleView(View convertView, ViewGroup parent) {
View result = convertView;
if (result == null) {
result = inflater.inflate(R.layout.com_facebook_picker_activity_circle_row, null);
}
ProgressBar activityCircle = (ProgressBar) result.findViewById(R.id.com_facebook_picker_row_activity_circle);
activityCircle.setVisibility(View.VISIBLE);
return result;
}
protected int getGraphObjectRowLayoutId(T graphObject) {
return R.layout.com_facebook_picker_list_row;
}
protected int getDefaultPicture() {
return R.drawable.com_facebook_profile_default_icon;
}
protected View createGraphObjectView(T graphObject, View convertView) {
View result = inflater.inflate(getGraphObjectRowLayoutId(graphObject), null);
ViewStub checkboxStub = (ViewStub) result.findViewById(R.id.com_facebook_picker_checkbox_stub);
if (checkboxStub != null) {
if (!getShowCheckbox()) {
checkboxStub.setVisibility(View.GONE);
} else {
CheckBox checkBox = (CheckBox) checkboxStub.inflate();
updateCheckboxState(checkBox, false);
}
}
ViewStub profilePicStub = (ViewStub) result.findViewById(R.id.com_facebook_picker_profile_pic_stub);
if (!getShowPicture()) {
profilePicStub.setVisibility(View.GONE);
} else {
ImageView imageView = (ImageView) profilePicStub.inflate();
imageView.setVisibility(View.VISIBLE);
}
return result;
}
protected void populateGraphObjectView(View view, T graphObject) {
String id = getIdOfGraphObject(graphObject);
view.setTag(id);
CharSequence title = getTitleOfGraphObject(graphObject);
TextView titleView = (TextView) view.findViewById(R.id.com_facebook_picker_title);
if (titleView != null) {
titleView.setText(title, TextView.BufferType.SPANNABLE);
}
CharSequence subtitle = getSubTitleOfGraphObject(graphObject);
TextView subtitleView = (TextView) view.findViewById(R.id.picker_subtitle);
if (subtitleView != null) {
if (subtitle != null) {
subtitleView.setText(subtitle, TextView.BufferType.SPANNABLE);
subtitleView.setVisibility(View.VISIBLE);
} else {
subtitleView.setVisibility(View.GONE);
}
}
if (getShowCheckbox()) {
CheckBox checkBox = (CheckBox) view.findViewById(R.id.com_facebook_picker_checkbox);
updateCheckboxState(checkBox, isGraphObjectSelected(id));
}
if (getShowPicture()) {
URL pictureURL = getPictureUrlOfGraphObject(graphObject);
if (pictureURL != null) {
ImageView profilePic = (ImageView) view.findViewById(R.id.com_facebook_picker_image);
// See if we have already pre-fetched this; if not, download it.
if (prefetchedPictureCache.containsKey(id)) {
ImageResponse response = prefetchedPictureCache.get(id);
profilePic.setImageBitmap(response.getBitmap());
profilePic.setTag(response.getRequest().getImageUrl());
} else {
downloadProfilePicture(id, pictureURL, profilePic);
}
}
}
}
/**
* @throws FacebookException if the GraphObject doesn't have an ID.
*/
String getIdOfGraphObject(T graphObject) {
if (graphObject.asMap().containsKey(ID)) {
Object obj = graphObject.getProperty(ID);
if (obj instanceof String) {
return (String) obj;
}
}
throw new FacebookException("Received an object without an ID.");
}
boolean filterIncludesItem(T graphObject) {
return filter == null || filter.includeItem(graphObject);
}
Filter<T> getFilter() {
return filter;
}
void setFilter(Filter<T> filter) {
this.filter = filter;
}
boolean isGraphObjectSelected(String graphObjectId) {
return false;
}
void updateCheckboxState(CheckBox checkBox, boolean graphObjectSelected) {
// Default is no-op
}
String getPictureFieldSpecifier() {
// How big is our image?
View view = createGraphObjectView(null, null);
ImageView picture = (ImageView) view.findViewById(R.id.com_facebook_picker_image);
if (picture == null) {
return null;
}
// Note: these dimensions are in pixels, not dips
ViewGroup.LayoutParams layoutParams = picture.getLayoutParams();
return String.format("picture.height(%d).width(%d)", layoutParams.height, layoutParams.width);
}
private boolean shouldShowActivityCircleCell() {
// We show the "more data" activity circle cell if we have a listener to request more data,
// we are expecting more data, and we have some data already (i.e., not on a fresh query).
return (cursor != null) && cursor.areMoreObjectsAvailable() && (dataNeededListener != null) && !isEmpty();
}
private void rebuildSections() {
sectionKeys = new ArrayList<String>();
graphObjectsBySection = new HashMap<String, ArrayList<T>>();
graphObjectsById = new HashMap<String, T>();
displaySections = false;
if (cursor == null || cursor.getCount() == 0) {
return;
}
int objectsAdded = 0;
cursor.moveToFirst();
do {
T graphObject = cursor.getGraphObject();
if (!filterIncludesItem(graphObject)) {
continue;
}
objectsAdded++;
String sectionKeyOfItem = getSectionKeyOfGraphObject(graphObject);
if (!graphObjectsBySection.containsKey(sectionKeyOfItem)) {
sectionKeys.add(sectionKeyOfItem);
graphObjectsBySection.put(sectionKeyOfItem, new ArrayList<T>());
}
List<T> section = graphObjectsBySection.get(sectionKeyOfItem);
section.add(graphObject);
graphObjectsById.put(getIdOfGraphObject(graphObject), graphObject);
} while (cursor.moveToNext());
if (sortFields != null) {
final Collator collator = Collator.getInstance();
for (List<T> section : graphObjectsBySection.values()) {
Collections.sort(section, new Comparator<GraphObject>() {
@Override
public int compare(GraphObject a, GraphObject b) {
return compareGraphObjects(a, b, sortFields, collator);
}
});
}
}
Collections.sort(sectionKeys, Collator.getInstance());
displaySections = sectionKeys.size() > 1 && objectsAdded > DISPLAY_SECTIONS_THRESHOLD;
}
SectionAndItem<T> getSectionAndItem(int position) {
if (sectionKeys.size() == 0) {
return null;
}
String sectionKey = null;
T graphObject = null;
if (!displaySections) {
sectionKey = sectionKeys.get(0);
List<T> section = graphObjectsBySection.get(sectionKey);
if (position >= 0 && position < section.size()) {
graphObject = graphObjectsBySection.get(sectionKey).get(position);
} else {
// We are off the end; we must be adding an activity circle to indicate more data is coming.
assert dataNeededListener != null && cursor.areMoreObjectsAvailable();
// We return null for both to indicate this.
return new SectionAndItem<T>(null, null);
}
} else {
// Count through the sections; the "0" position in each section is the header. We decrement
// position each time we skip forward a certain number of elements, including the header.
for (String key : sectionKeys) {
// Decrement if we skip over the header
if (position-- == 0) {
sectionKey = key;
break;
}
List<T> section = graphObjectsBySection.get(key);
if (position < section.size()) {
// The position is somewhere in this section. Get the corresponding graph object.
sectionKey = key;
graphObject = section.get(position);
break;
}
// Decrement by as many items as we skipped over
position -= section.size();
}
}
if (sectionKey != null) {
// Note: graphObject will be null if this represents a section header.
return new SectionAndItem<T>(sectionKey, graphObject);
} else {
throw new IndexOutOfBoundsException("position");
}
}
int getPosition(String sectionKey, T graphObject) {
int position = 0;
boolean found = false;
// First find the section key and increment position one for each header we will render;
// increment by the size of each section prior to the one we want.
for (String key : sectionKeys) {
if (displaySections) {
position++;
}
if (key.equals(sectionKey)) {
found = true;
break;
} else {
position += graphObjectsBySection.get(key).size();
}
}
if (!found) {
return -1;
} else if (graphObject == null) {
// null represents the header for a section; we counted this header in position earlier,
// so subtract it back out.
return position - (displaySections ? 1 : 0);
}
// Now find index of this item within that section.
for (T t : graphObjectsBySection.get(sectionKey)) {
if (GraphObject.Factory.hasSameId(t, graphObject)) {
return position;
}
position++;
}
return -1;
}
@Override
public boolean isEmpty() {
// We'll never populate sectionKeys unless we have at least one object.
return sectionKeys.size() == 0;
}
@Override
public int getCount() {
if (sectionKeys.size() == 0) {
return 0;
}
// If we are not displaying sections, we don't display a header; otherwise, we have one header per item in
// addition to the actual items.
int count = (displaySections) ? sectionKeys.size() : 0;
for (List<T> section : graphObjectsBySection.values()) {
count += section.size();
}
// If we should show a cell with an activity circle indicating more data is coming, add it to the count.
if (shouldShowActivityCircleCell()) {
++count;
}
return count;
}
@Override
public boolean areAllItemsEnabled() {
return displaySections;
}
@Override
public boolean hasStableIds() {
return true;
}
@Override
public boolean isEnabled(int position) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(position);
return sectionAndItem.getType() == SectionAndItem.Type.GRAPH_OBJECT;
}
@Override
public Object getItem(int position) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(position);
return (sectionAndItem.getType() == SectionAndItem.Type.GRAPH_OBJECT) ? sectionAndItem.graphObject : null;
}
@Override
public long getItemId(int position) {
// We assume IDs that can be converted to longs. If this is not the case for certain types of
// GraphObjects, subclasses should override this to return, e.g., position, and override hasStableIds
// to return false.
SectionAndItem<T> sectionAndItem = getSectionAndItem(position);
if (sectionAndItem != null && sectionAndItem.graphObject != null) {
String id = getIdOfGraphObject(sectionAndItem.graphObject);
if (id != null) {
return Long.parseLong(id);
}
}
return 0;
}
@Override
public int getViewTypeCount() {
return 3;
}
@Override
public int getItemViewType(int position) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(position);
switch (sectionAndItem.getType()) {
case SECTION_HEADER:
return HEADER_VIEW_TYPE;
case GRAPH_OBJECT:
return GRAPH_OBJECT_VIEW_TYPE;
case ACTIVITY_CIRCLE:
return ACTIVITY_CIRCLE_VIEW_TYPE;
default:
throw new FacebookException("Unexpected type of section and item.");
}
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(position);
switch (sectionAndItem.getType()) {
case SECTION_HEADER:
return getSectionHeaderView(sectionAndItem.sectionKey, convertView, parent);
case GRAPH_OBJECT:
return getGraphObjectView(sectionAndItem.graphObject, convertView, parent);
case ACTIVITY_CIRCLE:
// If we get a request for this view, it means we need more data.
assert cursor.areMoreObjectsAvailable() && (dataNeededListener != null);
dataNeededListener.onDataNeeded();
return getActivityCircleView(convertView, parent);
default:
throw new FacebookException("Unexpected type of section and item.");
}
}
@Override
public Object[] getSections() {
if (displaySections) {
return sectionKeys.toArray();
} else {
return new Object[0];
}
}
@Override
public int getPositionForSection(int section) {
if (displaySections) {
section = Math.max(0, Math.min(section, sectionKeys.size() - 1));
if (section < sectionKeys.size()) {
return getPosition(sectionKeys.get(section), null);
}
}
return 0;
}
@Override
public int getSectionForPosition(int position) {
SectionAndItem<T> sectionAndItem = getSectionAndItem(position);
if (sectionAndItem != null &&
sectionAndItem.getType() != SectionAndItem.Type.ACTIVITY_CIRCLE) {
return Math.max(0, Math.min(sectionKeys.indexOf(sectionAndItem.sectionKey), sectionKeys.size() - 1));
}
return 0;
}
public List<T> getGraphObjectsById(Collection<String> ids) {
Set<String> idSet = new HashSet<String>();
idSet.addAll(ids);
ArrayList<T> result = new ArrayList<T>(idSet.size());
for (String id : idSet) {
T graphObject = graphObjectsById.get(id);
if (graphObject != null) {
result.add(graphObject);
}
}
return result;
}
private void downloadProfilePicture(final String profileId, URL pictureURL, final ImageView imageView) {
if (pictureURL == null) {
return;
}
// If we don't have an imageView, we are pre-fetching this image to store in-memory because we
// think the user might scroll to its corresponding list row. If we do have an imageView, we
// only want to queue a download if the view's tag isn't already set to the URL (which would mean
// it's already got the correct picture).
boolean prefetching = imageView == null;
if (prefetching || !pictureURL.equals(imageView.getTag())) {
if (!prefetching) {
// Setting the tag to the profile ID indicates that we're currently downloading the
// picture for this profile; we'll set it to the actual picture URL when complete.
imageView.setTag(profileId);
imageView.setImageResource(getDefaultPicture());
}
ImageRequest.Builder builder = new ImageRequest.Builder(context.getApplicationContext(), pictureURL)
.setCallerTag(this)
.setCallback(
new ImageRequest.Callback() {
@Override
public void onCompleted(ImageResponse response) {
processImageResponse(response, profileId, imageView);
}
});
ImageRequest newRequest = builder.build();
pendingRequests.put(profileId, newRequest);
ImageDownloader.downloadAsync(newRequest);
}
}
private void processImageResponse(ImageResponse response, String graphObjectId, ImageView imageView) {
pendingRequests.remove(graphObjectId);
if (imageView == null) {
// This was a pre-fetch request.
if (response.getBitmap() != null) {
// Is the cache too big?
if (prefetchedPictureCache.size() >= MAX_PREFETCHED_PICTURES) {
// Find the oldest one and remove it.
String oldestId = prefetchedProfilePictureIds.remove(0);
prefetchedPictureCache.remove(oldestId);
}
prefetchedPictureCache.put(graphObjectId, response);
}
} else if (imageView != null && graphObjectId.equals(imageView.getTag())) {
Exception error = response.getError();
Bitmap bitmap = response.getBitmap();
if (error == null && bitmap != null) {
imageView.setImageBitmap(bitmap);
imageView.setTag(response.getRequest().getImageUrl());
}
}
}
private static int compareGraphObjects(GraphObject a, GraphObject b, Collection<String> sortFields,
Collator collator) {
for (String sortField : sortFields) {
String sa = (String) a.getProperty(sortField);
String sb = (String) b.getProperty(sortField);
if (sa != null && sb != null) {
int result = collator.compare(sa, sb);
if (result != 0) {
return result;
}
} else if (!(sa == null && sb == null)) {
return (sa == null) ? -1 : 1;
}
}
return 0;
}
// Graph object type to navigate the JSON that sometimes comes back instead of a URL string
private interface ItemPicture extends GraphObject {
ItemPictureData getData();
}
// Graph object type to navigate the JSON that sometimes comes back instead of a URL string
private interface ItemPictureData extends GraphObject {
String getUrl();
}
}