QCheckComboBox for Easy Multiple Items Selection

examples/check_combobox.py

@@ -0,0 +1,44 @@
+from qtpy.QtWidgets import QApplication, QMainWindow, QPushButton, QVBoxLayout, QWidget
+
+from superqt import QCheckComboBox
+
+
+def change_label_type() -> None:
+    """Function used to swtich the label type"""
+    if combobox.labelType() == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS:
+        combobox.setLabelType(QCheckComboBox.QCheckComboBoxLabelType.STRING)
+        combobox.setLabelText("Select Sample")
+    else:
+        combobox.setLabelType(QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS)
+
+
+# Create main window
+app = QApplication([])
+main_window = QMainWindow()
+main_widget = QWidget()
+main_layout = QVBoxLayout()
+main_window.setFixedWidth(700)
+main_window.setFixedHeight(450)
+
+# Create the check comobobox
+combobox = QCheckComboBox()
+combobox.setLabelText("Select items")
+texts = [f"Item {i}" for i in range(5)]
+combobox.addItems(texts)
+
+# Use insertItem instead of addItems
+combobox.insertItem(1, text="New Item at index 1")
+
+# Add button to change the label type
+button = QPushButton("Change label type")
+button.clicked.connect(lambda: change_label_type())
+
+# Add widgets to main window
+main_widget.setLayout(main_layout)
+main_widget.layout().addWidget(combobox)
+main_widget.layout().addWidget(button)
+main_window.setCentralWidget(main_widget)
+main_window.show()
+
+# Run
+app.exec_()

src/superqt/__init__.py

@@ -11,7 +11,7 @@
 
 from ._eliding_label import QElidingLabel
 from .collapsible import QCollapsible
-from .combobox import QEnumComboBox, QSearchableComboBox
+from .combobox import QCheckComboBox, QEnumComboBox, QSearchableComboBox
 from .selection import QSearchableListWidget
 from .sliders import (
     QDoubleRangeSlider,
@@ -28,6 +28,7 @@
 __all__ = [
     "ensure_main_thread",
     "ensure_object_thread",
+    "QCheckComboBox",
     "QDoubleRangeSlider",
     "QCollapsible",
     "QDoubleSlider",

src/superqt/combobox/__init__.py

@@ -1,4 +1,5 @@
+from ._check_combobox import QCheckComboBox
 from ._enum_combobox import QEnumComboBox
 from ._searchable_combo_box import QSearchableComboBox
 
-__all__ = ("QEnumComboBox", "QSearchableComboBox")
+__all__ = ("QEnumComboBox", "QSearchableComboBox", "QCheckComboBox")

src/superqt/combobox/_check_combobox.py

@@ -0,0 +1,189 @@
+from enum import Enum, auto
+from typing import Any, List, Union
+
+from qtpy.QtCore import QEvent, Qt, Signal
+from qtpy.QtGui import QIcon, QStandardItem
+from qtpy.QtWidgets import QComboBox, QStyle, QStyleOptionComboBox, QStylePainter
+
+
+class QCheckComboBox(QComboBox):
+    """
+    A combobox with a check for each item inserted.
+    based on https://stackoverflow.com/questions/47575880/qcombobox-set-title-text-regardless-of-items.
+    """
+
+    class QCheckComboBoxLabelType(Enum):
+        """Label type."""
+
+        STRING = auto()
+        SELECTED_ITEMS = auto()
+
+    _label_text: str = "Select items"
+    _label_type: QCheckComboBoxLabelType = QCheckComboBoxLabelType.STRING
+    selectionUpdated = Signal(int, bool)
+
+    def __init__(self) -> None:
+        """Initializes the widget."""
+        super().__init__()
+        self.view().pressed.connect(self._handleItemPressed)
+        self.view().doubleClicked.connect(self._handleItemPressed)
+        self._changed = False
+
+    def _update_label_text_with_selected_items(self) -> None:
+        checked_indices = self.checkedIndices()
+        selected_text_list = []
+        for index in checked_indices:
+            selected_text_list.append(self.itemText(index))
+        self.setLabelText(", ".join(selected_text_list))
+
+    def setLabelText(self, label_text: str) -> None:
+        """Sets the label text."""
+        self._label_text = label_text
+        self.repaint()
+
+    def labelText(self) -> str:
+        return self._label_text
+
+    def setLabelType(self, label_type: QCheckComboBoxLabelType) -> None:
+        """Sets the label type."""
+        self._label_type = label_type
+        if label_type == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS:
+            self._update_label_text_with_selected_items()
+
+    def labelType(self) -> QCheckComboBoxLabelType:
+        """Returns label type."""
+        return self._label_type
+
+    def _handleItemPressed(self, index: int) -> None:
+        """Updates item checked status."""
+        item = self.model().itemFromIndex(index)
+        if item.checkState() == Qt.Checked:
+            item.setCheckState(Qt.Unchecked)
+        else:
+            item.setCheckState(Qt.Checked)
+
+        if self._label_type == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS:
+            self._update_label_text_with_selected_items()
+        self._changed = True
+
+    def addItem(
+        self, text: str, icon: QIcon = None, userData: Any = None, checked: bool = True
+    ) -> None:
+        """Overrides the combobox additem to make sure it is chackable."""
+        super().addItem(text, userData)
+        item: QStandardItem = self.model().item(self.count() - 1, self.modelColumn())
+        item.setCheckable(True)
+        self.setItemChecked(self.count() - 1, checked=checked)
+        if icon:
+            item.setIcon(icon)
+        if (
+            self._label_type == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS
+            and checked is True
+        ):
+            self._update_label_text_with_selected_items()
+
+    def addItems(
+        self, texts: List[str], checked: Union[bool, List[bool]] = True
+    ) -> None:
+        """Overirdes the combobox addItems to make sure it is checkable."""
+        if isinstance(checked, bool):
+            checked = [checked] * len(texts)
+
+        for text, checked_value in zip(texts, checked):
+            self.addItem(text=text, userData=None, checked=checked_value)
+
+        if (
+            self._label_type == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS
+            and any(checked) is True
+        ):
+            self._update_label_text_with_selected_items()
+
+    def insertItem(
+        self,
+        index: int,
+        text: str,
+        icon: QIcon = None,
+        userData: Any = ...,
+        checked: bool = True,
+    ) -> None:
+        """Inserts an item."""
+        super().insertItem(index, text, userData)
+        item: QStandardItem = self.model().item(index, self.modelColumn())
+        item.setCheckable(True)
+        self.setItemChecked(index, checked=checked)
+        if icon:
+            item.setIcon(icon)
+        if (
+            self._label_type == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS
+            and checked is True
+        ):
+            self._update_label_text_with_selected_items()
+
+    def hidePopup(self) -> None:
+        """Override hidePopup to disable it if an item state has changed."""
+        if not self._changed:
+            super().hidePopup()
+        self._changed = False
+
+    def itemChecked(self, index: int) -> bool:
+        """Returns current checked state as boolean."""
+        item: QStandardItem = self.model().item(index, self.modelColumn())
+        is_checked: bool = item.checkState() == Qt.Checked
+        return is_checked
+
+    def setItemChecked(self, index: int, checked: bool = True) -> None:
+        """Sets the status."""
+        item: QStandardItem = self.model().item(index)
+        checked_state_old = item.checkState()
+        checked_state_new = Qt.Checked if checked else Qt.Unchecked
+
+        # Stopping condition
+        if checked_state_old == checked_state_new:
+            return
+
+        item.setCheckState(checked_state_new)
+        self.selectionUpdated.emit(index, checked)
+
+        if self._label_type == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS:
+            self._update_label_text_with_selected_items()
+
+    def setAllItemChecked(self, checked: bool = True) -> None:
+        """Set all item checked status in one go."""
+        for i in range(self.count()):
+            self.setItemChecked(i, checked=checked)
+
+    def checkedIndices(self) -> List[int]:
+        """Returns the checked indices."""
+        indecies = []
+        for i in range(self.count()):
+            item = self.model().item(i)
+            if item.checkState() == Qt.Checked:
+                indecies.append(i)
+        return indecies
+
+    def uncheckedIndices(self) -> List[int]:
+        """Returns teh unchecked indices."""
+        indecies = []
+        for i in range(self.count()):
+            item = self.model().item(i)
+            if item.checkState() == Qt.Unchecked:
+                indecies.append(i)
+        return indecies
+
+    def checkedTexts(self) -> List[str]:
+        """Returns the checked indices."""
+        texts = []
+        for i in range(self.count()):
+            item = self.model().item(i)
+            if item.checkState() == Qt.Checked:
+                texts.append(item.text())
+        return texts
+
+    def paintEvent(self, event: QEvent) -> None:
+        """Overrides the paint event to update the label."""
+        painter = QStylePainter(self)
+        opt = QStyleOptionComboBox()
+        self.initStyleOption(opt)
+        opt.currentText = self._label_text
+        painter.drawComplexControl(QStyle.CC_ComboBox, opt)
+        painter.drawControl(QStyle.CE_ComboBoxLabel, opt)

tests/test_check_combobox.py

@@ -0,0 +1,140 @@
+from pytestqt.qtbot import QtBot
+from qtpy.QtCore import QEvent
+
+from superqt import QCheckComboBox
+
+
+def test_add_item(qtbot: QtBot) -> None:
+    """Tests the addition of item"""
+
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+
+    check_combobox.addItem("Item 1", userData=1, checked=False)
+    check_combobox.addItem("Item 2", userData="2", checked=True)
+
+    assert check_combobox.itemData(0) == 1
+    assert check_combobox.itemData(1) == "2"
+    assert check_combobox.itemText(0) == "Item 1"
+    assert check_combobox.itemText(1) == "Item 2"
+
+
+def test_add_items(qtbot: QtBot) -> None:
+    """Tests the addition of items"""
+
+    check_combobox1 = QCheckComboBox()
+    qtbot.add_widget(check_combobox1)
+    check_combobox1.addItems(["Item 1", "Item 2", "Item 3"])
+    assert check_combobox1.itemText(0) == "Item 1"
+    assert check_combobox1.itemText(1) == "Item 2"
+    assert check_combobox1.itemText(2) == "Item 3"
+
+    check_combobox2 = QCheckComboBox()
+    qtbot.add_widget(check_combobox2)
+    check_combobox2.addItems(["Item 1", "Item 2"], checked=False)
+    assert check_combobox2.itemChecked(0) is False
+    assert check_combobox2.itemChecked(1) is False
+
+    check_combobox3 = QCheckComboBox()
+    qtbot.add_widget(check_combobox3)
+    check_combobox3.addItems(["Item 1", "Item 2"], checked=True)
+    assert check_combobox3.itemChecked(0) is True
+    assert check_combobox3.itemChecked(1) is True
+
+    check_combobox4 = QCheckComboBox()
+    qtbot.add_widget(check_combobox4)
+    check_combobox4.addItems(["Item 1", "Item 2"], checked=[True, False])
+    assert check_combobox4.itemChecked(0) is True
+    assert check_combobox4.itemChecked(1) is False
+
+
+def test_set_all_items_checked(qtbot: QtBot) -> None:
+    """Tests setting all items checked status"""
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox.addItems(["Item 1", "Item 2", "Item 3"], checked=[True, False, True])
+    checked_status = [
+        check_combobox.itemChecked(i) for i in range(check_combobox.count())
+    ]
+    assert checked_status == [True, False, True]
+
+    check_combobox.setAllItemChecked(False)
+    checked_status = [
+        check_combobox.itemChecked(i) for i in range(check_combobox.count())
+    ]
+    assert checked_status == [False, False, False]
+
+    check_combobox.setAllItemChecked(True)
+    checked_status = [
+        check_combobox.itemChecked(i) for i in range(check_combobox.count())
+    ]
+    assert checked_status == [True, True, True]
+
+
+def test_indices_retrival(qtbot: QtBot) -> None:
+    """Tests retrival of the indices checked and unchecked"""
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox.addItems(["Item 1", "Item 2", "Item 3"], checked=[True, False, True])
+    assert check_combobox.checkedIndices() == [0, 2]
+    assert check_combobox.uncheckedIndices() == [1]
+
+
+def test_changing_label_string(qtbot: QtBot) -> None:
+    """Tests changing the label string"""
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox.setLabelText("Please select items")
+    assert check_combobox.labelText() == "Please select items"
+
+
+def test_selected_items_label_type(qtbot: QtBot) -> None:
+    """Tests selected item label"""
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox.setLabelType(QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS)
+    assert (
+        check_combobox.labelType()
+        == QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS
+    )
+
+    check_combobox.addItem("Item 1")
+    check_combobox.addItems(["Item 2", "Item 3"])
+    check_combobox.setItemChecked(1, False)
+    assert check_combobox.labelText() == "Item 1, Item 3"
+
+
+def test_paint_event(qtbot: QtBot) -> None:
+    """Simple test for paint event; execute without error"""
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox.show()
+    check_combobox.setLabelText("A new label")
+    check_combobox.paintEvent(QEvent(QEvent.Paint))
+    check_combobox.hide()
+
+
+def test_hidepopup(qtbot: QtBot) -> None:
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox._changed = True
+    check_combobox.hidePopup()
+    assert check_combobox._changed is False
+    check_combobox.hidePopup()
+
+
+def test_handle_item_checked(qtbot: QtBot) -> None:
+    """Tests the check combobox interactions"""
+    check_combobox = QCheckComboBox()
+    qtbot.add_widget(check_combobox)
+    check_combobox.addItems(["Item 1", "Item 2"], [True, False])
+    check_combobox.setLabelType(QCheckComboBox.QCheckComboBoxLabelType.SELECTED_ITEMS)
+    model = check_combobox.model()
+
+    model_index = model.index(0, 0)
+    check_combobox._handleItemPressed(model_index)
+    assert check_combobox.itemChecked(0) is False
+
+    model_index = model.index(1, 0)
+    check_combobox._handleItemPressed(model_index)
+    assert check_combobox.itemChecked(1) is True