Create a data view to simplify table view creation

bliss/flint/widgets/data_views.py

+# -*- coding: utf-8 -*-
+#
+# This file is part of the bliss project
+#
+# Copyright (c) 2015-2020 Beamline Control Unit, ESRF
+# Distributed under the GNU LGPLv3. See LICENSE for more info.
+
+from __future__ import annotations
+
+import logging
+import typing
+from silx.gui import qt
+from . import delegates
+
+
+_logger = logging.getLogger(__name__)
+
+
+class ObjectListModel(qt.QAbstractItemModel):
+    """Store a list of object as a Qt model.
+
+    For now, it only supports to set the whole list. No move or remove
+    actions are supported.
+    """
+
+    def __init__(self, parent=None):
+        super(ObjectListModel, self).__init__(parent=parent)
+        self.__items: typing.List[object] = []
+        self.__delegatedColumns = set()
+        self.__columns = 1
+        self.__columnTitle = {}
+
+    def setObjectList(self, items: typing.List[object]):
+        self.beginResetModel()
+        self.__items = list(items)
+        self.endResetModel()
+
+    def setColumn(self, columnId: int, title: str, delegated=False):
+        self.beginResetModel()
+        if delegated:
+            self.__delegatedColumns.add(columnId)
+        self.__columns = max(self.__columns, columnId + 1)
+        self.__columnTitle[columnId] = title
+        self.endResetModel()
+
+    def rowCount(self, parent: qt.QModelIndex = qt.QModelIndex()):
+        return len(self.__items)
+
+    def index(self, row, column, parent=qt.QModelIndex()):
+        if 0 <= row < len(self.__items):
+            return self.createIndex(row, column)
+        else:
+            return qt.QModelIndex()
+
+    def objectIndex(self, obj):
+        try:
+            row = self.__items.index(obj)
+            return self.index(row, 0)
+        except IndexError:
+            return qt.QModelIndex()
+
+    def object(self, index: qt.QModelIndex):
+        return self.data(index, role=delegates.ObjectRole)
+
+    def parent(self, index: qt.QModelIndex):
+        return qt.QModelIndex()
+
+    def flags(self, index: qt.QModelIndex):
+        defaultFlags = qt.QAbstractItemModel.flags(self, index)
+        if index.isValid():
+            if index.column() in self.__delegatedColumns:
+                return qt.Qt.ItemIsEditable | defaultFlags
+        return defaultFlags
+
+    def data(self, index: qt.QModelIndex, role: int = qt.Qt.DisplayRole):
+        row = index.row()
+        col = index.column()
+        item = self.__items[row]
+        if role == qt.Qt.DisplayRole:
+            # Basic rendering
+            if col in self.__delegatedColumns:
+                return None
+            return f"{str(item)}"
+        elif role == delegates.ObjectRole:
+            return item
+
+    def headerData(
+        self,
+        section: int,
+        orientation: qt.Qt.Orientation,
+        role: int = qt.Qt.DisplayRole,
+    ):
+        if role == qt.Qt.DisplayRole:
+            if orientation == qt.Qt.Horizontal:
+                return self.__columnTitle.get(section, str(section))
+        return super(ObjectListModel, self).headerData(section, orientation, role)
+
+    def columnCount(self, parent: qt.QModelIndex = qt.QModelIndex()):
+        return self.__columns
+
+
+class VDataTableView(qt.QTableView):
+    """
+    Table view containing a single object per row which is displayed
+    using many columns.
+
+    The default behaviour is to display columns as item delegate.
+    Therefor, the method `setColumn` is used to define the layout of the table.
+    """
+
+    def __init__(self, parent=None):
+        super(VDataTableView, self).__init__(parent=parent)
+        self.__columnsDelegated = set()
+        self.setEditTriggers(qt.QAbstractItemView.NoEditTriggers)
+        self.setSelectionBehavior(qt.QAbstractItemView.SelectRows)
+        self.setSelectionMode(qt.QAbstractItemView.SingleSelection)
+        header = self.horizontalHeader()
+        header.setHighlightSections(False)
+
+    def setModel(self, model: qt.QAbstractItemModel):
+        if model is not None and not isinstance(model, ObjectListModel):
+            raise ValueError(f"Unsupported model {type(model)}")
+        previousModel = self.model()
+        if previousModel is not None:
+            previousModel.modelReset.disconnect(self.__modelWasReset)
+        qt.QTableView.setModel(self, model)
+        if model is not None:
+            model.modelReset.connect(self.__modelWasReset)
+        self.__modelWasReset()
+
+    def __modelWasReset(self):
+        """
+        Enforce that each editors are open.
+        """
+        model = self.model()
+        for c in self.__columnsDelegated:
+            for r in range(model.rowCount()):
+                index = model.index(r, c)
+                self.openPersistentEditor(index)
+
+    def setColumn(
+        self,
+        columnId: int,
+        title: str,
+        delegate: typing.Union[
+            typing.Type[qt.QAbstractItemDelegate], qt.QAbstractItemDelegate
+        ] = None,
+        resizeMode: qt.QHeaderView.ResizeMode = None,
+    ):
+        """
+        Define a column.
+
+        Arguments:
+            columnId: Logical column id
+            title: Title of this column
+            delegate: An item delegate instance or class
+            resizeMode: Mode used to resize the column
+        """
+        model = self.model()
+        model.setColumn(columnId, title=title, delegated=delegate is not None)
+        if resizeMode is not None:
+            header = self.horizontalHeader()
+            header.setSectionResizeMode(columnId, resizeMode)
+        if delegate is not None:
+            if issubclass(delegate, qt.QAbstractItemDelegate):
+                delegate = delegate(self)
+            self.__columnsDelegated.add(columnId)
+            self.setItemDelegateForColumn(columnId, delegate)

bliss/flint/widgets/delegates.py

@@ -38,6 +38,7 @@ VisibilityRole = qt.Qt.UserRole + 101
 RadioRole = qt.Qt.UserRole + 102
 CheckRole = qt.Qt.UserRole + 103
 FlintModelRole = qt.Qt.UserRole + 104
+ObjectRole = qt.Qt.UserRole + 105
 
 
 _colormapPixmap: Dict[str, qt.QPixmap] = {}