com.btmura.android.reddit.app.ThingPagerAdapter.java Source code

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Here is the source code for com.btmura.android.reddit.app.ThingPagerAdapter.java

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/*
 * Copyright (C) 2012 Brian Muramatsu
 *
 * 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.btmura.android.reddit.app;

import android.content.Context;
import android.os.Bundle;
import android.os.Parcelable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.util.Log;

import com.btmura.android.reddit.BuildConfig;
import com.btmura.android.reddit.content.ThingDataLoader.ThingData;
import com.btmura.android.reddit.database.Kinds;

import java.util.ArrayList;

/**
 * {@link FragmentStateItemPagerAdapter} for controlling what is shown in the
 * ViewPager for looking at a thing. In multipane layouts, it is responsible for
 * handling the right side of the screen.
 */
public class ThingPagerAdapter extends FragmentStateItemPagerAdapter {

    public static final String TAG = "ThingPagerAdapter";

    public static final int TYPE_LINK = 0;
    public static final int TYPE_COMMENTS = 1;
    public static final int TYPE_MESSAGE = 2;

    public static final int PAGE_LINK = TYPE_LINK;
    public static final int PAGE_COMMENTS = TYPE_COMMENTS;

    private static final String STATE_PAGE_TYPES = "pageTypes";
    private static final String STATE_OLD_PAGE_TYPES = "oldPageTypes";

    private final ArrayList<Integer> pageTypes = new ArrayList<Integer>(2);
    private final ArrayList<Integer> oldPageTypes = new ArrayList<Integer>(2);
    private final Context context;
    private final String accountName;
    private final ThingData thingData;

    public ThingPagerAdapter(Context context, FragmentManager fm, String accountName, ThingData thingData) {
        super(fm);
        this.context = context.getApplicationContext();
        this.accountName = accountName;
        this.thingData = thingData;
        setupPages(thingData.parent);
    }

    @Override
    public Parcelable saveState() {
        Bundle state = (Bundle) super.saveState();
        if (state != null) {
            state.putIntegerArrayList(STATE_PAGE_TYPES, pageTypes);
            state.putIntegerArrayList(STATE_OLD_PAGE_TYPES, oldPageTypes);
        }
        return state;
    }

    @Override
    public void restoreState(Parcelable state, ClassLoader loader) {
        super.restoreState(state, loader);
        if (state != null) {
            Bundle bundle = (Bundle) state;
            pageTypes.clear();
            pageTypes.addAll(bundle.getIntegerArrayList(STATE_PAGE_TYPES));
            oldPageTypes.clear();
            oldPageTypes.addAll(bundle.getIntegerArrayList(STATE_OLD_PAGE_TYPES));
            notifyDataSetChanged();
        }
    }

    private void setupPages(ThingBundle thingBundle) {
        switch (thingBundle.getKind()) {
        case Kinds.KIND_LINK:
            if (thingBundle.hasLinkUrl()) {
                addPage(TYPE_LINK);
            }
            addPage(TYPE_COMMENTS);
            break;

        case Kinds.KIND_MESSAGE:
            addPage(TYPE_MESSAGE);
            break;
        }
    }

    public void addPage(int type) {
        addPage(pageTypes.size(), type);
    }

    public void addPage(int index, int type) {
        oldPageTypes.clear();
        oldPageTypes.addAll(pageTypes);
        pageTypes.add(index, type);
        notifyDataSetChanged();
    }

    public int getPageType(int position) {
        return pageTypes.get(position);
    }

    public int findPageType(int type) {
        int count = pageTypes.size();
        for (int i = 0; i < count; i++) {
            if (pageTypes.get(i) == type) {
                return i;
            }
        }
        return 0;
    }

    @Override
    public int getItemPosition(Object object) {
        int type = object instanceof LinkFragment ? TYPE_LINK : TYPE_COMMENTS;

        int oldPosition = -1;
        for (int i = 0; i < oldPageTypes.size(); i++) {
            if (type == oldPageTypes.get(i)) {
                oldPosition = i;
                break;
            }
        }

        int newPosition = -1;
        for (int i = 0; i < pageTypes.size(); i++) {
            if (type == pageTypes.get(i)) {
                newPosition = i;
                break;
            }
        }

        if (newPosition == -1) {
            if (BuildConfig.DEBUG) {
                Log.d(TAG, "getItemPosition: " + oldPageTypes + " -> " + pageTypes + " = NONE");
            }
            return POSITION_NONE;
        }

        if (oldPosition == newPosition) {
            if (BuildConfig.DEBUG) {
                Log.d(TAG, "getItemPosition: " + oldPageTypes + " -> " + pageTypes + " = UNCHANGED");
            }
            return POSITION_UNCHANGED;
        }

        if (BuildConfig.DEBUG) {
            Log.d(TAG, "getItemPosition: " + oldPageTypes + " -> " + pageTypes + " = " + newPosition);
        }
        return newPosition;
    }

    @Override
    public long getItemId(int position) {
        return pageTypes.get(position);
    }

    @Override
    public int getCount() {
        return pageTypes.size();
    }

    @Override
    public Fragment getItem(int position) {
        if (BuildConfig.DEBUG) {
            Log.d(TAG, "getItem: " + position + " -> " + pageTypes.get(position));
        }
        switch (pageTypes.get(position)) {
        case TYPE_LINK:
            String url = thingData.parent.getLinkUrl().toString();
            if (YouTubePlayerFragment.isPlayableWithYouTube(context, url)) {
                return YouTubePlayerFragment.newInstance(url);
            } else {
                return LinkFragment.newInstance(url);
            }

        case TYPE_COMMENTS:
            // TODO: Standardize parentId/childId selector throughout app.
            if (thingData.child != null) {
                return CommentListFragment.newInstance(accountName, thingData.child.getThingId(),
                        thingData.parent.getThingId());
            } else {
                return CommentListFragment.newInstance(accountName, thingData.parent.getThingId(), null);
            }

        case TYPE_MESSAGE:
            return MessageThreadListFragment.newInstance(accountName, thingData.parent.getThingId());

        default:
            throw new IllegalArgumentException();
        }
    }
}