Add copy, paste, cut, delete keyboard shortcuts to Table widget (#264)

* add copy, paste, cut, delete

* fix copy

* fix imports

* add read only

* add tests

* add assert

* simplify

magicgui/backends/_qtpy/widgets.py

@@ -7,7 +7,15 @@
 import qtpy
 from qtpy import QtWidgets as QtW
 from qtpy.QtCore import QEvent, QObject, Qt, Signal
-from qtpy.QtGui import QFont, QFontMetrics, QImage, QPixmap, QResizeEvent, QTextDocument
+from qtpy.QtGui import (
+    QFont,
+    QFontMetrics,
+    QImage,
+    QKeyEvent,
+    QPixmap,
+    QResizeEvent,
+    QTextDocument,
+)
 
 from magicgui.types import FileDialogMode
 from magicgui.widgets import _protocols
@@ -886,19 +894,112 @@ def _maybefloat(item):
         return num
 
 
+class _QTableExtended(QtW.QTableWidget):
+    _read_only: bool = False
+
+    def _copy_to_clipboard(self):
+        selranges = self.selectedRanges()
+        if not selranges:
+            return
+        if len(selranges) > 1:
+            import warnings
+
+            warnings.warn(
+                "Multiple table selections detected: "
+                "only the first (upper left) selection will be copied"
+            )
+
+        # copy first selection range
+        sel = selranges[0]
+        lines = []
+        for r in range(sel.topRow(), sel.bottomRow() + 1):
+            cells = []
+            for c in range(sel.leftColumn(), sel.rightColumn() + 1):
+                item = self.item(r, c)
+                cells.append(item.text()) if hasattr(item, "text") else ""
+            lines.append("\t".join(cells))
+
+        if lines:
+            QtW.QApplication.clipboard().setText("\n".join(lines))
+
+    def _paste_from_clipboard(self):
+        if self._read_only:
+            return
+
+        sel_idx = self.selectedIndexes()
+        if not sel_idx:
+            return
+        text = QtW.QApplication.clipboard().text()
+        if not text:
+            return
+
+        # paste in the text
+        row0, col0 = sel_idx[0].row(), sel_idx[0].column()
+        data = [line.split("\t") for line in text.splitlines()]
+        if (row0 + len(data)) > self.rowCount():
+            self.setRowCount(row0 + len(data))
+        if data and (col0 + len(data[0])) > self.columnCount():
+            self.setColumnCount(col0 + len(data[0]))
+        for r, line in enumerate(data):
+            for c, cell in enumerate(line):
+                try:
+                    self.item(row0 + r, col0 + c).setText(str(cell))
+                except AttributeError:
+                    self.setItem(row0 + r, col0 + c, QtW.QTableWidgetItem(str(cell)))
+
+        # select what was just pasted
+        selrange = QtW.QTableWidgetSelectionRange(row0, col0, row0 + r, col0 + c)
+        self.clearSelection()
+        self.setRangeSelected(selrange, True)
+
+    def _delete_selection(self):
+        if self._read_only:
+            return
+
+        for item in self.selectedItems():
+            try:
+                item.setText("")
+            except AttributeError:
+                pass
+
+    def keyPressEvent(self, e: QKeyEvent):
+        if e.modifiers() & Qt.ControlModifier and e.key() == Qt.Key_C:
+            return self._copy_to_clipboard()
+        if e.modifiers() & Qt.ControlModifier and e.key() == Qt.Key_V:
+            return self._paste_from_clipboard()
+        if e.modifiers() & Qt.ControlModifier and e.key() == Qt.Key_X:
+            self._copy_to_clipboard()
+            return self._delete_selection()
+        if e.key() in (Qt.Key_Delete, Qt.Key_Backspace):
+            return self._delete_selection()
+        return super().keyPressEvent(e)
+
+
 class Table(QBaseWidget, _protocols.TableWidgetProtocol):
-    _qwidget: QtW.QTableWidget
+    _qwidget: _QTableExtended
     _DATA_ROLE: int = 255
+    _RO_FLAGS = Qt.ItemIsSelectable | Qt.ItemIsEnabled
+    _DEFAULT_FLAGS = Qt.ItemIsSelectable | Qt.ItemIsEditable | Qt.ItemIsEnabled
 
     def __init__(self):
-        super().__init__(QtW.QTableWidget)
+        super().__init__(_QTableExtended)
         header = self._qwidget.horizontalHeader()
         # avoid strange AttributeError on CI
         if hasattr(header, "setSectionResizeMode"):
             header.setSectionResizeMode(QtW.QHeaderView.Stretch)
         # self._qwidget.horizontalHeader().setSectionsMovable(True)  # tricky!!
         self._qwidget.itemChanged.connect(self._update_item_data_with_text)
 
+    def _mgui_set_read_only(self, value: bool) -> None:
+        self._qwidget._read_only = bool(value)
+        flags = Table._RO_FLAGS if value else Table._DEFAULT_FLAGS
+        for row in range(self._qwidget.rowCount()):
+            for col in range(self._qwidget.columnCount()):
+                self._qwidget.item(row, col).setFlags(flags)
+
+    def _mgui_get_read_only(self) -> bool:
+        return self._qwidget._read_only
+
     def _update_item_data_with_text(self, item: QtW.QTableWidgetItem):
         self._qwidget.blockSignals(True)
         item.setData(self._DATA_ROLE, _maybefloat(item.text()))

magicgui/widgets/_protocols.py

@@ -194,7 +194,22 @@ def _mgui_bind_change_callback(self, callback: Callable[[Any], Any]) -> None:
 
 
 @runtime_checkable
-class TableWidgetProtocol(WidgetProtocol, Protocol):
+class SupportsReadOnly(Protocol):
+    """Widget that can be read_only."""
+
+    @abstractmethod
+    def _mgui_set_read_only(self, value: bool) -> None:
+        """Set read_only."""
+        raise NotImplementedError()
+
+    @abstractmethod
+    def _mgui_get_read_only(self) -> bool:
+        """Get read_only status."""
+        raise NotImplementedError()
+
+
+@runtime_checkable
+class TableWidgetProtocol(WidgetProtocol, SupportsReadOnly, Protocol):
     """ValueWidget subclass intended for 2D tabular data, with row & column headers."""
 
     @abstractmethod
@@ -374,21 +389,6 @@ def _mgui_get_text(self) -> str:
         raise NotImplementedError()
 
 
-@runtime_checkable
-class SupportsReadOnly(Protocol):
-    """Widget that can be read_only."""
-
-    @abstractmethod
-    def _mgui_set_read_only(self, value: bool) -> None:
-        """Set read_only."""
-        raise NotImplementedError()
-
-    @abstractmethod
-    def _mgui_get_read_only(self) -> bool:
-        """Get read_only status."""
-        raise NotImplementedError()
-
-
 @runtime_checkable
 class ButtonWidgetProtocol(ValueWidgetProtocol, SupportsText, Protocol):
     """The "value" in a ButtonWidget is the current (checked) state."""

magicgui/widgets/_table.py

@@ -25,6 +25,7 @@
 from magicgui.application import use_app
 from magicgui.events import EventEmitter
 from magicgui.widgets._bases import Widget
+from magicgui.widgets._bases.mixins import _ReadOnlyMixin
 from magicgui.widgets._protocols import TableWidgetProtocol
 
 if TYPE_CHECKING:
@@ -128,7 +129,7 @@ def __repr__(self) -> str:
         return f"table_items({n} {self._axis}s)"
 
 
-class Table(Widget, MutableMapping[TblKey, list]):
+class Table(Widget, _ReadOnlyMixin, MutableMapping[TblKey, list]):
     """A table widget representing columnar or 2D data with headers.
 
     Tables behave like plain `dicts`, where the keys are column headers and the

tests/test_table.py

@@ -340,3 +340,51 @@ def test_check_new_headers():
     with pytest.raises(ValueError) as e:
         table.row_headers = ("a", "b", "c", "d")
         assert "Length mismatch" in str(e)
+
+
+# these are Qt-specific
+
+
+def test_copy(qapp):
+    from qtpy.QtWidgets import QTableWidgetSelectionRange
+
+    table = Table(value=_TABLE_DATA["data"])
+    selrange = QTableWidgetSelectionRange(1, 1, 0, 0)
+    table.native.setRangeSelected(selrange, True)
+    table.native._copy_to_clipboard()
+    assert qapp.clipboard().text() == "1\t2\n4\t5"
+
+
+def test_paste(qapp):
+    from qtpy.QtWidgets import QTableWidgetSelectionRange
+
+    table = Table(value=_TABLE_DATA["data"])
+    selrange = QTableWidgetSelectionRange(1, 1, 0, 0)
+    table.native.setRangeSelected(selrange, True)
+    qapp.clipboard().setText("0\t0\n1\t1")
+
+    table.read_only = True
+    table.native._paste_from_clipboard()
+    assert table.data.to_list() == [[1, 2, 3], [4, 5, 6]]
+
+    table.read_only = False
+    table.native._paste_from_clipboard()
+    assert table.data.to_list() == [[0, 0, 3], [1, 1, 6]]
+
+
+def test_delete(qapp):
+    from qtpy.QtWidgets import QTableWidgetSelectionRange
+
+    table = Table(value=_TABLE_DATA["data"])
+    selrange = QTableWidgetSelectionRange(1, 1, 0, 0)
+    table.native.setRangeSelected(selrange, True)
+
+    table.read_only = True
+    assert table.read_only
+    table.native._delete_selection()
+    assert table.data.to_list() == [[1, 2, 3], [4, 5, 6]]
+
+    table.read_only = False
+    assert not table.read_only
+    table.native._delete_selection()
+    assert table.data.to_list() == [[None, None, 3], [None, None, 6]]