Add clear button; Disable buttons when function unavailable

banking_breakdown/ui.py

@@ -90,6 +90,8 @@ class MainWindow(QMainWindow):
             = self.findChild(QPushButton, "deleteCategoryButton")
         self._apply_button \
             = self.findChild(QPushButton, "applyCategoryButton")
+        self._clear_button \
+            = self.findChild(QPushButton, "clearCategoryButton")
         self._list_widget \
             = self.findChild(QListWidget, "categoryListWidget")
         self._table_view \
@@ -101,6 +103,7 @@ class MainWindow(QMainWindow):
 
         self._create_button.clicked.connect(self._handle_create_click)
         self._delete_button.clicked.connect(self._handle_delete_click)
+        self._clear_button.clicked.connect(self._handle_clear_click)
         self._apply_button.clicked.connect(self._handle_apply_click)
         self._list_widget.itemActivated.connect(self._handle_item_double_click)
 
@@ -110,6 +113,9 @@ class MainWindow(QMainWindow):
         header.setContextMenuPolicy(Qt.ContextMenuPolicy.CustomContextMenu)
         header.customContextMenuRequested.connect(self._header_right_clicked)
 
+        self._list_widget.itemSelectionChanged.connect(
+            self._handle_list_selection_changed)
+
     def set_statement_data(self, df: pd.DataFrame):
         if 'category' not in df.columns:
             df['category'] = [' '] * len(df.index)
@@ -132,6 +138,13 @@ class MainWindow(QMainWindow):
         self._show_warnings(df)
         self._update_categories_from_dataframe(df)
 
+        # Upon reloading the data, the selection is cleared but no signal
+        # is generated. Manually call the signal handler
+        self._handle_table_selection_changed()
+
+        self._table_view.selectionModel().selectionChanged.connect(
+            self._handle_table_selection_changed)
+
     def get_statement_data(self) -> pd.DataFrame:
         return self._table_view.model().sourceModel().get_dataframe()
 
@@ -294,6 +307,9 @@ class MainWindow(QMainWindow):
             df = self.get_statement_data()
             df.loc[df['category'] == selected_item.text(), 'category'] = ' '
 
+    def _handle_clear_click(self):
+        self._assign_category(' ')
+
     def _assign_category(self, category: str):
         indexes = self._table_view.selectionModel().selectedRows()
 
@@ -320,6 +336,38 @@ class MainWindow(QMainWindow):
         df = self.get_statement_data()
         df.to_csv(filename, index=False)
 
+    def _check_enable_delete_button(self):
+        if len(self._list_widget.selectedItems()) > 0:
+            self._delete_button.setEnabled(True)
+        else:
+            self._delete_button.setEnabled(False)
+
+    def _check_enable_clear_button(self):
+        if len(self._table_view.selectionModel().selectedRows()) > 0:
+            self._clear_button.setEnabled(True)
+        else:
+            self._clear_button.setEnabled(False)
+
+    def _check_enable_apply_button(self):
+        if ((len(self._table_view.selectionModel().selectedRows()) > 0)
+                and (len(self._list_widget.selectedItems()) > 0)):
+            self._apply_button.setEnabled(True)
+        else:
+            self._apply_button.setEnabled(False)
+
+    def _handle_list_selection_changed(self):
+        self._check_enable_delete_button()
+        self._check_enable_apply_button()
+
+    def _handle_table_selection_changed(self):
+        self._check_enable_clear_button()
+        self._check_enable_apply_button()
+
+
+#
+# Other functions
+#
+
 
 def show_main_window(df: pd.DataFrame = None):
     app = QApplication(sys.argv)
@@ -336,9 +384,6 @@ def main():
     import os
     os.chdir("../")
 
-    categories = ["Food", "Rent & Utilities", "Hobbies", "Education",
-                  "Transportation", "Social Life", "Other"]
-
     df = pd.read_csv("res/bank_statement_2023_categorized_renamed.csv")
 
     show_main_window(df)