LadderAdapter.java

package com.jasonrobinson.racer.adapter;

import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.Paint;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import com.jasonrobinson.racer.R;
import com.jasonrobinson.racer.model.Ladder.Entry;
import com.jasonrobinson.racer.model.Ladder.Entry.Character;

import java.math.BigDecimal;
import java.math.MathContext;

public class LadderAdapter extends BaseAdapter {

    private Entry[] mPreviousEntries;
    private Entry[] mEntries;

    private boolean mUseClassRank;
    private boolean mBorderFirstItem;

    public LadderAdapter(Entry[] entries, boolean useClassRank, boolean borderFirstItem) {

        mEntries = entries;
        mUseClassRank = useClassRank;
        mBorderFirstItem = borderFirstItem;
    }

    @Override
    public int getCount() {

        return mEntries.length;
    }

    @Override
    public Entry getItem(int position) {

        return mEntries[position];
    }

    @Override
    public long getItemId(int position) {

        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        Context context = parent.getContext();
        View view = convertView;
        if (view == null) {
            view = LayoutInflater.from(context).inflate(R.layout.ladder_item, parent, false);
            view.setTag(new ViewHolder(view));
        }

        ViewHolder holder = (ViewHolder) view.getTag();
        holder.bottomBorderView.setVisibility(mBorderFirstItem && position == 0 ? View.VISIBLE : View.INVISIBLE);

        Entry entry = getItem(position);
        Character character = entry.getCharacter();

        holder.rankTextView.setText(Integer.toString(mUseClassRank ? entry.getClassRank() : entry.getRank()));
        holder.nameTextView.setText(character.getName());
        if (entry.isDead()) {
            holder.nameTextView.setPaintFlags(holder.nameTextView.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG);
        } else {
            holder.nameTextView.setPaintFlags(holder.nameTextView.getPaintFlags() & (~Paint.STRIKE_THRU_TEXT_FLAG));
        }

        holder.levelTextView.setText(Integer.toString(character.getLevel()));
        holder.classTextView.setText(character.getPoeClass());
        holder.experienceTextView.setText(formatExperience(character.getExperience()));

        applyRankChange(parent.getContext(), view, entry);

        return view;
    }

    @SuppressWarnings("deprecation")
    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    private void applyRankChange(Context context, View v, Entry entry) {

        RankChange rankChange = getRankChange(entry);
        Drawable drawable;
        switch (rankChange) {
            case UP:
                drawable = new ColorDrawable(context.getResources().getColor(R.color.rank_up));
                break;
            case DOWN:
                drawable = new ColorDrawable(context.getResources().getColor(R.color.rank_down));
                break;
            case NONE:
            default:
                drawable = new ColorDrawable(context.getResources().getColor(R.color.rank_none));
                break;
        }

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
            v.setBackground(drawable);
        } else {
            v.setBackgroundDrawable(drawable);
        }
    }

    private CharSequence formatExperience(long experience) {

        MathContext mc = new MathContext(4);
        if (experience >= 1000000000) { // billion
            return new BigDecimal((double) experience / 1000000000).round(mc).toString() + "B";
        } else if (experience >= 1000000) { // million
            return new BigDecimal((double) experience / 1000000).round(mc).toString() + "M";
        } else if (experience >= 1000) { // thousand
            return new BigDecimal((double) experience / 1000).round(mc).toString() + "K";
        }

        return Long.toString(experience);
    }

    private RankChange getRankChange(Entry entry) {

        if (mPreviousEntries == null) {
            return RankChange.NONE;
        }

        Entry prevEntry = findPreviousEntry(entry);
        if (prevEntry == null || entry.getRank() > prevEntry.getRank()) {
            return RankChange.UP;
        } else if (entry.getRank() < prevEntry.getRank()) {
            return RankChange.DOWN;
        }

        return RankChange.NONE;
    }

    private Entry findPreviousEntry(Entry entry) {

        if (mPreviousEntries == null) {
            return null;
        }

        String character = entry.getCharacter().getName();
        for (Entry prevEntry : mPreviousEntries) {
            String prevCharacter = prevEntry.getCharacter().getName();
            if (character.equals(prevCharacter)) {
                return prevEntry;
            }
        }

        return null;
    }

    public void setEntries(Entry[] entries, boolean useClassRank) {

        mPreviousEntries = mEntries;
        mEntries = entries;
        mUseClassRank = useClassRank;

        notifyDataSetChanged();
    }

    public void setBorderFirstItem(boolean enable) {

        mBorderFirstItem = enable;
    }

    private enum RankChange {
        UP,
        DOWN,
        NONE
    }

    private class ViewHolder {

        public TextView rankTextView;
        public TextView nameTextView;
        public TextView levelTextView;
        public TextView classTextView;
        public TextView experienceTextView;
        public View bottomBorderView;

        public ViewHolder(View v) {

            rankTextView = (TextView) v.findViewById(R.id.rank);
            nameTextView = (TextView) v.findViewById(R.id.name);
            levelTextView = (TextView) v.findViewById(R.id.level);
            classTextView = (TextView) v.findViewById(R.id.poeClass);
            experienceTextView = (TextView) v.findViewById(R.id.experience);
            bottomBorderView = v.findViewById(R.id.bottomBorder);
        }
    }
}