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.LedgerTransaction;
  32 import net.ktnx.mobileledger.model.TransactionListItem;
  33 import net.ktnx.mobileledger.utils.Logger;
  34 import net.ktnx.mobileledger.utils.Misc;
  35
  36 import java.util.List;
  37 import java.util.Locale;
  38
  39 public class TransactionListAdapter extends RecyclerView.Adapter<TransactionRowHolderBase> {
  40     private final AsyncListDiffer<TransactionListItem> listDiffer;
  41     public TransactionListAdapter() {
  42         super();
  43
  44         listDiffer = new AsyncListDiffer<>(this, new DiffUtil.ItemCallback<TransactionListItem>() {
  45             @Override
  46             public boolean areItemsTheSame(@NonNull TransactionListItem oldItem,
  47                                            @NonNull TransactionListItem newItem) {
  48                 if (oldItem.getType() != newItem.getType())
  49                     return false;
  50                 switch (oldItem.getType()) {
  51                     case DELIMITER:
  52                         return (oldItem.getDate()
  53                                        .equals(newItem.getDate()));
  54                     case TRANSACTION:
  55                         return oldItem.getTransaction()
  56                                       .getLedgerId() == newItem.getTransaction()
  57                                                                .getLedgerId();
  58                     case HEADER:
  59                         return true;    // there can be only one header
  60                     default:
  61                         throw new IllegalStateException(
  62                                 String.format(Locale.US, "Unexpected transaction item type %s",
  63                                         oldItem.getType()));
  64                 }
  65             }
  66             @Override
  67             public boolean areContentsTheSame(@NonNull TransactionListItem oldItem,
  68                                               @NonNull TransactionListItem newItem) {
  69                 switch (oldItem.getType()) {
  70                     case DELIMITER:
  71                         // Delimiters items are "same" for same dates and the contents are the date
  72                         return true;
  73                     case TRANSACTION:
  74                         return oldItem.getTransaction()
  75                                       .equals(newItem.getTransaction()) &&
  76                                Misc.equalStrings(oldItem.getBoldAccountName(),
  77                                        newItem.getBoldAccountName());
  78                     case HEADER:
  79                         // headers don't differ in their contents. they observe the last update
  80                         // date and react to its changes
  81                         return true;
  82                     default:
  83                         throw new IllegalStateException(
  84                                 String.format(Locale.US, "Unexpected transaction item type %s",
  85                                         oldItem.getType()));
  86
  87                 }
  88             }
  89         });
  90     }
  91     @Override
  92     public int getItemViewType(int position) {
  93         return listDiffer.getCurrentList()
  94                          .get(position)
  95                          .getType()
  96                          .ordinal();
  97     }
  98     public void onBindViewHolder(@NonNull TransactionRowHolderBase holder, int position) {
  99         TransactionListItem item = listDiffer.getCurrentList()
 100                                              .get(position);
 101
 102         // in a race when transaction value is reduced, but the model hasn't been notified yet
 103         // the view will disappear when the notifications reaches the model, so by simply omitting
 104         // the out-of-range get() call nothing bad happens - just a to-be-deleted view remains
 105         // a bit longer
 106         if (item == null)
 107             return;
 108
 109         final TransactionListItem.Type newType = item.getType();
 110
 111         switch (newType) {
 112             case TRANSACTION:
 113                 LedgerTransaction tr = item.getTransaction();
 114                 holder.asTransaction()
 115                       .bind(tr, item.getBoldAccountName());
 116
 117                 break;
 118             case DELIMITER:
 119                 holder.asDelimiter()
 120                       .bind(item);
 121                 break;
 122             case HEADER:
 123                 holder.asHeader()
 124                       .bind();
 125
 126                 break;
 127             default:
 128                 throw new IllegalStateException("Unexpected value: " + newType);
 129         }
 130     }
 131     @NonNull
 132     @Override
 133     public TransactionRowHolderBase onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
 134 //        debug("perf", "onCreateViewHolder called");
 135         final LayoutInflater inflater = LayoutInflater.from(parent.getContext());
 136
 137         switch (TransactionListItem.Type.valueOf(viewType)) {
 138             case TRANSACTION:
 139                 return new TransactionRowHolder(
 140                         TransactionListRowBinding.inflate(inflater, parent, false));
 141             case DELIMITER:
 142                 return new TransactionListDelimiterRowHolder(
 143                         TransactionDelimiterBinding.inflate(inflater, parent, false));
 144             case HEADER:
 145                 return new TransactionListLastUpdateRowHolder(
 146                         LastUpdateLayoutBinding.inflate(inflater, parent, false));
 147             default:
 148                 throw new IllegalStateException("Unexpected value: " + viewType);
 149         }
 150     }
 151
 152     @Override
 153     public int getItemCount() {
 154         return listDiffer.getCurrentList()
 155                          .size();
 156     }
 157     public void setTransactions(List<TransactionListItem> newList) {
 158         Logger.debug("transactions",
 159                 String.format(Locale.US, "Got new transaction list (%d items)", newList.size()));
 160         listDiffer.submitList(newList);
 161     }
 162 }