app/src/main/java/net/ktnx/mobileledger/ui/transaction_list/TransactionListAdapter.java

   1 /*
   2  * Copyright © 2021 Damyan Ivanov.
   3  * This file is part of MoLe.
   4  * MoLe is free software: you can distribute it and/or modify it
   5  * under the term of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your opinion), any later version.
   8  *
   9  * MoLe is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12  * GNU General Public License terms for details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with MoLe. If not, see <https://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.ktnx.mobileledger.ui.transaction_list;
  19
  20 import android.view.LayoutInflater;
  21 import android.view.ViewGroup;
  22
  23 import androidx.annotation.NonNull;
  24 import androidx.recyclerview.widget.AsyncListDiffer;
  25 import androidx.recyclerview.widget.DiffUtil;
  26 import androidx.recyclerview.widget.RecyclerView;
  27
  28 import net.ktnx.mobileledger.databinding.LastUpdateLayoutBinding;
  29 import net.ktnx.mobileledger.databinding.TransactionDelimiterBinding;
  30 import net.ktnx.mobileledger.databinding.TransactionListRowBinding;
  31 import net.ktnx.mobileledger.model.TransactionListItem;
  32 import net.ktnx.mobileledger.utils.Logger;
  33 import net.ktnx.mobileledger.utils.Misc;
  34
  35 import java.util.List;
  36 import java.util.Locale;
  37
  38 public class TransactionListAdapter extends RecyclerView.Adapter<TransactionRowHolderBase> {
  39     private final AsyncListDiffer<TransactionListItem> listDiffer;
  40     public TransactionListAdapter() {
  41         super();
  42
  43         setHasStableIds(true);
  44
  45         listDiffer = new AsyncListDiffer<>(this, new DiffUtil.ItemCallback<TransactionListItem>() {
  46             @Override
  47             public boolean areItemsTheSame(@NonNull TransactionListItem oldItem,
  48                                            @NonNull TransactionListItem newItem) {
  49                 if (oldItem.getType() != newItem.getType())
  50                     return false;
  51                 switch (oldItem.getType()) {
  52                     case DELIMITER:
  53                         return (oldItem.getDate()
  54                                        .equals(newItem.getDate()));
  55                     case TRANSACTION:
  56                         return oldItem.getTransaction()
  57                                       .getLedgerId() == newItem.getTransaction()
  58                                                                .getLedgerId();
  59                     case HEADER:
  60                         return true;    // there can be only one header
  61                     default:
  62                         throw new IllegalStateException(
  63                                 String.format(Locale.US, "Unexpected transaction item type %s",
  64                                         oldItem.getType()));
  65                 }
  66             }
  67             @Override
  68             public boolean areContentsTheSame(@NonNull TransactionListItem oldItem,
  69                                               @NonNull TransactionListItem newItem) {
  70                 switch (oldItem.getType()) {
  71                     case DELIMITER:
  72                         return oldItem.isMonthShown() == newItem.isMonthShown();
  73                     case TRANSACTION:
  74                         return oldItem.getTransaction()
  75                                       .equals(newItem.getTransaction()) &&
  76                                Misc.equalStrings(oldItem.getBoldAccountName(),
  77                                        newItem.getBoldAccountName()) &&
  78                                Misc.equalStrings(oldItem.getRunningTotal(),
  79                                        newItem.getRunningTotal());
  80                     case HEADER:
  81                         // headers don't differ in their contents. they observe the last update
  82                         // date and react to its changes
  83                         return true;
  84                     default:
  85                         throw new IllegalStateException(
  86                                 String.format(Locale.US, "Unexpected transaction item type %s",
  87                                         oldItem.getType()));
  88
  89                 }
  90             }
  91         });
  92     }
  93     @Override
  94     public long getItemId(int position) {
  95         TransactionListItem item = listDiffer.getCurrentList()
  96                                              .get(position);
  97         switch (item.getType()) {
  98             case HEADER:
  99                 return -1;
 100             case TRANSACTION:
 101                 return item.getTransaction()
 102                            .getLedgerId();
 103             case DELIMITER:
 104                 return -item.getDate()
 105                             .toDate()
 106                             .getTime();
 107             default:
 108                 throw new IllegalStateException("Unexpected value: " + item.getType());
 109         }
 110     }
 111     @Override
 112     public int getItemViewType(int position) {
 113         return listDiffer.getCurrentList()
 114                          .get(position)
 115                          .getType()
 116                          .ordinal();
 117     }
 118     public void onBindViewHolder(@NonNull TransactionRowHolderBase holder, int position) {
 119         TransactionListItem item = listDiffer.getCurrentList()
 120                                              .get(position);
 121
 122         // in a race when transaction value is reduced, but the model hasn't been notified yet
 123         // the view will disappear when the notifications reaches the model, so by simply omitting
 124         // the out-of-range get() call nothing bad happens - just a to-be-deleted view remains
 125         // a bit longer
 126         if (item == null)
 127             return;
 128
 129         final TransactionListItem.Type newType = item.getType();
 130
 131         switch (newType) {
 132             case TRANSACTION:
 133                 holder.asTransaction()
 134                       .bind(item, item.getBoldAccountName());
 135
 136                 break;
 137             case DELIMITER:
 138                 holder.asDelimiter()
 139                       .bind(item);
 140                 break;
 141             case HEADER:
 142                 holder.asHeader()
 143                       .bind();
 144
 145                 break;
 146             default:
 147                 throw new IllegalStateException("Unexpected value: " + newType);
 148         }
 149     }
 150     @NonNull
 151     @Override
 152     public TransactionRowHolderBase onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
 153 //        debug("perf", "onCreateViewHolder called");
 154         final LayoutInflater inflater = LayoutInflater.from(parent.getContext());
 155
 156         switch (TransactionListItem.Type.valueOf(viewType)) {
 157             case TRANSACTION:
 158                 return new TransactionRowHolder(
 159                         TransactionListRowBinding.inflate(inflater, parent, false));
 160             case DELIMITER:
 161                 return new TransactionListDelimiterRowHolder(
 162                         TransactionDelimiterBinding.inflate(inflater, parent, false));
 163             case HEADER:
 164                 return new TransactionListLastUpdateRowHolder(
 165                         LastUpdateLayoutBinding.inflate(inflater, parent, false));
 166             default:
 167                 throw new IllegalStateException("Unexpected value: " + viewType);
 168         }
 169     }
 170
 171     @Override
 172     public int getItemCount() {
 173         return listDiffer.getCurrentList()
 174                          .size();
 175     }
 176     public void setTransactions(List<TransactionListItem> newList) {
 177         Logger.debug("transactions",
 178                 String.format(Locale.US, "Got new transaction list (%d items)", newList.size()));
 179         listDiffer.submitList(newList);
 180     }
 181 }