Updated credit/debit handling to match Gnucash desktop - fixes #78

Now credit transactions decrease balance in Assets and Expenses accounts while debits increase the balance

Author: codinguser

app/src/org/gnucash/android/data/Account.java

@@ -54,8 +54,28 @@ public class Account {
 	 * This are the different types specified by the OFX format and 
 	 * they are currently not used except for exporting
 	 */
-	public enum AccountType {CASH, BANK, CREDIT, ASSET, LIABILITY, INCOME, EXPENSE,
-							PAYABLE, RECEIVABLE, EQUITY, CURRENCY, STOCK, MUTUAL, ROOT};
+	public enum AccountType {
+        CASH, BANK, CREDIT, ASSET(true), LIABILITY, INCOME, EXPENSE(true),
+        PAYABLE, RECEIVABLE, EQUITY, CURRENCY, STOCK, MUTUAL, ROOT;
+
+        /**
+         * Indicates that this type of account has an inverted state for credits and debits.
+         * Credits decrease the account balance, while debits increase it.
+         */
+        private boolean mInvertedCredit = false;
+
+        private AccountType(boolean invertedCredit){
+            mInvertedCredit = invertedCredit;
+        }
+
+        private AccountType() {
+            //nothing to see here, move along
+        }
+
+        public boolean hasInvertedCredit(){
+            return mInvertedCredit;
+        }
+    };
 
     /**
      * Accounts types which are used by the OFX standard

app/src/org/gnucash/android/db/AccountsDbAdapter.java

@@ -285,8 +285,17 @@ public AccountType getAccountType(String uid){
 		}
 		return AccountType.valueOf(type);
 	}
-	
-	/**
+
+    /**
+     * Overloaded method. Resolves the account unique ID from the row ID and makes a call to {@link #getAccountType(String)}
+     * @param accountId Database row ID of the account
+     * @return {@link AccountType} of the account
+     */
+    public AccountType getAccountType(long accountId){
+        return getAccountType(getAccountUID(accountId));
+    }
+
+    /**
 	 * Returns the name of the account with id <code>accountID</code>
 	 * @param accountID Database ID of the account record
 	 * @return Name of the account 

app/src/org/gnucash/android/ui/transactions/NewTransactionFragment.java

@@ -26,6 +26,7 @@
 
 import android.widget.*;
 import org.gnucash.android.R;
+import org.gnucash.android.data.Account;
 import org.gnucash.android.data.Money;
 import org.gnucash.android.data.Transaction;
 import org.gnucash.android.data.Transaction.TransactionType;
@@ -173,6 +174,12 @@ public class NewTransactionFragment extends SherlockFragment implements
      */
     boolean mAmountManuallyEdited = false;
 
+    /**
+     * The AccountType of the account to which this transaction belongs.
+     * Used for determining the accounting rules for credits and debits
+     */
+    Account.AccountType mAccountType;
+
 	/**
 	 * Create the view and retrieve references to the UI elements
 	 */
@@ -215,8 +222,12 @@ public void onActivityCreated(Bundle savedInstanceState) {
         long transactionId = getArguments().getLong(SELECTED_TRANSACTION_ID);
 		mTransactionsDbAdapter = new TransactionsDbAdapter(getActivity());
 		mTransaction = mTransactionsDbAdapter.getTransaction(transactionId);
-		
-		setListeners();
+
+        final long accountId = getArguments().getLong(TransactionsListFragment.SELECTED_ACCOUNT_ID);
+        mAccountType = mAccountsDbAdapter.getAccountType(accountId);
+        toggleTransactionTypeState();
+
+        setListeners();
 		if (mTransaction == null)
 			initalizeViews();
 		else {
@@ -229,6 +240,22 @@ public void onActivityCreated(Bundle savedInstanceState) {
         initTransactionNameAutocomplete();
 	}
 
+    private void toggleTransactionTypeState() {
+        switch (mAccountType) {
+            case ASSET:
+            case EXPENSE:
+                mTransactionTypeButton.setTextOff(getString(R.string.label_debit));
+                mTransactionTypeButton.setTextOn(getString(R.string.label_credit));
+                break;
+
+            default:
+                mTransactionTypeButton.setTextOff(getString(R.string.label_credit));
+                mTransactionTypeButton.setTextOn(getString(R.string.label_debit));
+                break;
+        }
+        mTransactionTypeButton.invalidate();
+    }
+
     /**
      * Initializes the transaction name field for autocompletion with existing transaction names in the database
      */
@@ -276,7 +303,6 @@ public void onItemClick(AdapterView<?> adapterView, View view, int position, lon
 	 * This method is called if the fragment is used for editing a transaction
 	 */
 	private void initializeViewsWithTransaction(){
-				
 		mNameEditText.setText(mTransaction.getName());
 		mTransactionTypeButton.setChecked(mTransaction.getTransactionType() == TransactionType.DEBIT);
 		if (!mAmountManuallyEdited){
@@ -315,11 +341,19 @@ private void initalizeViews() {
 		mDateTextView.setText(DATE_FORMATTER.format(time));
 		mTimeTextView.setText(TIME_FORMATTER.format(time));
 		mTime = mDate = Calendar.getInstance();
-				
+
 		String typePref = PreferenceManager.getDefaultSharedPreferences(getActivity()).getString(getString(R.string.key_default_transaction_type), "DEBIT");
 		if (typePref.equals("CREDIT")){
-			mTransactionTypeButton.setChecked(false);
-		}
+            if (mAccountType == Account.AccountType.ASSET || mAccountType == Account.AccountType.EXPENSE)
+                mTransactionTypeButton.setChecked(false);
+            else
+                mTransactionTypeButton.setChecked(true);
+		} else {
+            if (mAccountType == Account.AccountType.ASSET || mAccountType == Account.AccountType.EXPENSE)
+                mTransactionTypeButton.setChecked(true);
+            else
+                mTransactionTypeButton.setChecked(false);
+        }
 
 		final long accountId = getArguments().getLong(TransactionsListFragment.SELECTED_ACCOUNT_ID);
 		String code = Money.DEFAULT_CURRENCY_CODE;
@@ -455,7 +489,16 @@ public void onAccountChanged(long newAccountId){
 		String currencyCode = accountsDbAdapter.getCurrencyCode(newAccountId);
 		Currency currency = Currency.getInstance(currencyCode);
 		mCurrencyTextView.setText(currency.getSymbol(Locale.getDefault()));
-		
+
+        Account.AccountType previousAccountType = mAccountType;
+        mAccountType = accountsDbAdapter.getAccountType(newAccountId);
+        toggleTransactionTypeState();
+
+        //if the new account has a different credit/debit philosophy as the previous one, then toggle the button
+        if (mAccountType.hasInvertedCredit() != previousAccountType.hasInvertedCredit()){
+            mTransactionTypeButton.toggle();
+        }
+
 		updateTransferAccountsList();
 	}
 
@@ -478,7 +521,11 @@ private void saveNewTransaction() {
 		long accountID 	= ((TransactionsActivity) getSherlockActivity()).getCurrentAccountID(); 		
 		Currency currency = Currency.getInstance(mTransactionsDbAdapter.getCurrencyCode(accountID));
 		Money amount 	= new Money(amountBigd, currency);
-		TransactionType type = mTransactionTypeButton.isChecked() ? TransactionType.DEBIT : TransactionType.CREDIT;
+		TransactionType type;
+        if (mAccountType.hasInvertedCredit()){
+            type = amount.isNegative() ? TransactionType.CREDIT : TransactionType.DEBIT;
+        } else
+            type = amount.isNegative() ? TransactionType.DEBIT : TransactionType.CREDIT;
 		if (mTransaction != null){
 			mTransaction.setAmount(amount);
 			mTransaction.setName(name);

app/src/org/gnucash/android/ui/transactions/TransactionsActivity.java

@@ -170,6 +170,7 @@ protected void onCreate(Bundle savedInstanceState) {
             if (transactionId > 0) {
                 mSectionHeaderTransactions.setText(R.string.title_edit_transaction);
                 args.putLong(NewTransactionFragment.SELECTED_TRANSACTION_ID, transactionId);
+                args.putLong(TransactionsListFragment.SELECTED_ACCOUNT_ID, mAccountId);
             } else {
                 mSectionHeaderTransactions.setText(R.string.title_add_transaction);
                 args.putLong(TransactionsListFragment.SELECTED_ACCOUNT_ID, mAccountId);