Java tutorial
/* Yaaic - Yet Another Android IRC Client Copyright 2009-2013 Sebastian Kaspari This file is part of Yaaic. Yaaic is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. Yaaic is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Yaaic. If not, see <http://www.gnu.org/licenses/>. */ package indrora.atomic.adapter; import indrora.atomic.indicator.ConversationStateProvider; import indrora.atomic.listener.MessageClickListener; import indrora.atomic.model.Conversation; import indrora.atomic.model.Server; import indrora.atomic.view.MessageListView; import java.util.Collections; import java.util.HashMap; import java.util.LinkedList; import android.content.Context; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.view.View; import com.viewpagerindicator.TitlePageIndicator; /** * Adapter for displaying a pager of conversations. * * @author Sebastian Kaspari <sebastian@yaaic.org> */ public class ConversationPagerAdapter extends PagerAdapter implements ConversationStateProvider { public static final int COLOR_NONE = 0x0; public static final int COLOR_DEFAULT = 0xFFDDDDDD; public static final int COLOR_MESSAGE = 0xFF31B6E7; public static final int COLOR_HIGHLIGHT = 0xFFFFBB00; private final Server server; private LinkedList<ConversationInfo> conversations; private final HashMap<Integer, View> views; /** * Container class to remember conversation and view association. */ public class ConversationInfo implements Comparable<ConversationInfo> { public Conversation conv; public MessageListAdapter adapter; public MessageListView view; public ConversationInfo(Conversation conv) { this.conv = conv; this.adapter = null; this.view = null; } /** * Compares this ConversationInfo with another ConversationInfo. * This compares the two ConversationInfos by their Conversations. * * @param convInfo The ConversationInfo to compare */ @Override public int compareTo(ConversationInfo convInfo) { return conv.compareTo(convInfo.conv); } } /** * Create a new {@link ConversationPagerAdapter} instance. */ public ConversationPagerAdapter(Context context, Server server) { this.server = server; conversations = new LinkedList<ConversationInfo>(); views = new HashMap<Integer, View>(); } /** * Add a conversation to the adapter. * * @param conversation */ public void addConversation(Conversation conversation) { conversations.add(new ConversationInfo(conversation)); Collections.sort(conversations); notifyDataSetChanged(); } /** * Remove the conversation at the given position from the adapter. * * @param position */ public void removeConversation(int position) { conversations.remove(position); notifyDataSetChanged(); } /** * Get position of given item. */ @Override public int getItemPosition(Object object) { if (views.containsKey(object)) { return POSITION_UNCHANGED; } return POSITION_NONE; } /** * Get item at position */ public Conversation getItem(int position) { ConversationInfo convInfo = getItemInfo(position); if (convInfo != null) { return convInfo.conv; } else { return null; } } /** * Get the adapter of the {@link MessageListView} at the given position. * * @param position * @return */ public MessageListAdapter getItemAdapter(int position) { ConversationInfo convInfo = getItemInfo(position); if (convInfo != null) { return convInfo.adapter; } else { return null; } } /** * Get the adapter of the {@link MessageListView} for the conversation * with the given name. * * @param name * @return */ public MessageListAdapter getItemAdapter(String name) { return getItemAdapter(getPositionByName(name)); } /** * Get ConversationInfo on item at position * * @param position */ private ConversationInfo getItemInfo(int position) { if (position >= 0 && position < conversations.size()) { return conversations.get(position); } return null; } /** * Get an item by the channel's name * * @param channel * @return The item */ public int getPositionByName(String name) { // Optimization - cache field lookups int mSize = conversations.size(); LinkedList<ConversationInfo> mItems = this.conversations; for (int i = 0; i < mSize; i++) { if (mItems.get(i).conv.getName().equalsIgnoreCase(name)) { return i; } } return -1; } /** * Remove all conversations. */ public void clearConversations() { conversations = new LinkedList<ConversationInfo>(); } /** * Get number of conversations from this adapter. */ @Override public int getCount() { return conversations.size(); } /** * Determines whether a page View is associated with a specific key object. */ @Override public boolean isViewFromObject(View view, Object object) { return view == object; } /** * Create a view object for the conversation at the given position. */ @Override public Object instantiateItem(View collection, int position) { // ConversationInfo convInfo = getItemInfo(position); ConversationInfo convInfo = conversations.get(position); View view; if (convInfo.view != null) { view = convInfo.view; } else { view = renderConversation(convInfo, collection); } views.put(position, view); ((ViewPager) collection).addView(view); return view; } /** * Render the given conversation and return the new view. * * @param convInfo * @param parent * @return */ private MessageListView renderConversation(ConversationInfo convInfo, View parent) { MessageListView list = new MessageListView(parent.getContext()); convInfo.view = list; list.setOnItemClickListener(MessageClickListener.getInstance()); MessageListAdapter adapter = convInfo.adapter; if (adapter == null) { adapter = new MessageListAdapter(convInfo.conv, parent.getContext()); convInfo.adapter = adapter; } list.setAdapter(adapter); list.setSelection(adapter.getCount() - 1); // scroll to bottom return list; } /** * Remove the given view from the adapter and collection. */ @Override public void destroyItem(View collection, int position, Object view) { ((ViewPager) collection).removeView((View) view); views.remove(position); } /** * Get the title for the given position. Used by the {@link TitlePageIndicator}. */ @Override public String getPageTitle(int position) { Conversation conversation = getItem(position); if (conversation.getType() == Conversation.TYPE_SERVER) { return server.getTitle(); } else { return conversation.getName(); } } @Override public int getColorAt(int position) { Conversation conversation = getItem(position); switch (conversation.getStatus()) { case Conversation.STATUS_HIGHLIGHT: return COLOR_HIGHLIGHT; case Conversation.STATUS_MESSAGE: return COLOR_MESSAGE; default: return COLOR_DEFAULT; } } /** * Get the state color for all conversations lower than the given position. */ @Override public int getColorForLowerThan(int position) { int color = COLOR_NONE; for (int i = 0; i < position; i++) { int currentColor = getColorAt(i); if (currentColor == COLOR_HIGHLIGHT) { return COLOR_HIGHLIGHT; } if (currentColor == COLOR_MESSAGE) { color = COLOR_MESSAGE; } } return color; } /** * Get the state color for all conversations greater than the given position. */ @Override public int getColorForGreaterThan(int position) { int size = conversations.size(); int color = COLOR_NONE; for (int i = position + 1; i < size; i++) { int currentColor = getColorAt(i); if (currentColor == COLOR_HIGHLIGHT) { return COLOR_HIGHLIGHT; } if (currentColor == COLOR_MESSAGE) { color = COLOR_MESSAGE; } } return color; } }