[processing][needs-docs] Move batch execution double-click-to-fill-down

to an explicit widget in the table

The double-click-header action is very hidden, and many users will
not stumble upon this. By moving it to an explicit "Autofill" widget at the
top of the table, we make this important action much more user
discoverable.

It also gives the possibility of other, parameter specific, autofill
actions (e.g. fill by expression, fill by file pattern)

python/plugins/processing/gui/BatchAlgorithmDialog.py

@@ -78,7 +78,7 @@ def runAlgorithm(self):
         load_layers = self.mainWidget().checkLoadLayersOnCompletion.isChecked()
         project = QgsProject.instance() if load_layers else None
 
-        for row in range(self.mainWidget().tblParameters.rowCount()):
+        for row in range(len(self.mainWidget().batchRowCount())):
             col = 0
             parameters = {}
             for param in self.algorithm().parameterDefinitions():
@@ -98,7 +98,7 @@ def runAlgorithm(self):
                     continue
 
                 count_visible_outputs += 1
-                widget = self.mainWidget().tblParameters.cellWidget(row, col)
+                widget = self.mainWidget().tblParameters.cellWidget(row + 1, col)
                 text = widget.getValue()
                 if out.checkValueIsAcceptable(text):
                     if isinstance(out, (QgsProcessingParameterRasterDestination,

python/plugins/processing/gui/BatchPanel.py

@@ -30,8 +30,22 @@
 import warnings
 
 from qgis.PyQt import uic
-from qgis.PyQt.QtWidgets import QTableWidgetItem, QComboBox, QHeaderView, QFileDialog, QMessageBox
-from qgis.PyQt.QtCore import QDir, QFileInfo
+from qgis.PyQt.QtWidgets import (
+    QTableWidgetItem,
+    QComboBox,
+    QHeaderView,
+    QFileDialog,
+    QMessageBox,
+    QToolButton,
+    QMenu,
+    QAction
+)
+from qgis.PyQt.QtGui import QPalette
+from qgis.PyQt.QtCore import (
+    QDir,
+    QFileInfo,
+    QCoreApplication
+)
 from qgis.core import (Qgis,
                        QgsApplication,
                        QgsSettings,
@@ -59,6 +73,68 @@
         os.path.join(pluginPath, 'ui', 'widgetBatchPanel.ui'))
 
 
+class BatchPanelFillWidget(QToolButton):
+
+    def __init__(self, parameterDefinition, column, panel, parent=None):
+        super().__init__(parent)
+
+        self.setBackgroundRole(QPalette.Window)
+        self.setAutoFillBackground(True)
+
+        self.parameterDefinition = parameterDefinition
+        self.column = column
+        self.panel = panel
+
+        self.setText(QCoreApplication.translate('BatchPanel', 'Autofill…'))
+        f = self.font()
+        f.setItalic(True)
+        self.setFont(f)
+        self.setPopupMode(QToolButton.InstantPopup)
+        self.setAutoRaise(True)
+
+        self.menu = QMenu()
+        self.menu.aboutToShow.connect(self.createMenu)
+        self.setMenu(self.menu)
+
+    def createMenu(self):
+        self.menu.clear()
+        self.menu.setMinimumWidth(self.width())
+
+        fill_down_action = QAction(self.tr('Fill Down'), self.menu)
+        fill_down_action.triggered.connect(self.fillDown)
+        fill_down_action.setToolTip(self.tr('Copy the first value down to all other rows'))
+
+        self.menu.addAction(fill_down_action)
+
+    def fillDown(self):
+        """
+        Copy the top value down
+        """
+        context = dataobjects.createContext()
+
+        wrapper = self.panel.wrappers[0][self.column]
+        if wrapper is None:
+            # e.g. double clicking on a destination header
+            widget = self.panel.tblParameters.cellWidget(1, self.column)
+            value = widget.getValue()
+        else:
+            value = wrapper.parameterValue()
+
+        for row in range(1, self.panel.batchRowCount()):
+            self.setRowValue(row, value, context)
+
+    def setRowValue(self, row, value, context):
+        """
+        Sets the value for a row, in the current column
+        """
+        wrapper = self.panel.wrappers[row][self.column]
+        if wrapper is None:
+            # e.g. destination header
+            self.panel.tblParameters.cellWidget(row + 1, self.column).setValue(str(value))
+        else:
+            wrapper.setParameterValue(value, context)
+
+
 class BatchPanel(BASE, WIDGET):
 
     PARAMETERS = "PARAMETERS"
@@ -87,8 +163,6 @@ def __init__(self, parent, alg):
         self.btnOpen.clicked.connect(self.load)
         self.btnSave.clicked.connect(self.save)
         self.btnAdvanced.toggled.connect(self.toggleAdvancedMode)
-        self.tblParameters.horizontalHeader().sectionDoubleClicked.connect(
-            self.fillParameterValues)
 
         self.tblParameters.horizontalHeader().resizeSections(QHeaderView.ResizeToContents)
         self.tblParameters.horizontalHeader().setDefaultSectionSize(250)
@@ -107,6 +181,8 @@ def processingContext(self):
 
         self.context_generator = ContextGenerator(self.processing_context)
 
+        self.column_to_parameter_definition = {}
+
         self.initWidgets()
 
     def layerRegistryChanged(self):
@@ -132,21 +208,32 @@ def initWidgets(self):
                 column, QTableWidgetItem(param.description()))
             if param.flags() & QgsProcessingParameterDefinition.FlagAdvanced:
                 self.tblParameters.setColumnHidden(column, True)
+
+            self.column_to_parameter_definition[column] = param.name()
             column += 1
 
         for out in self.alg.destinationParameterDefinitions():
             if not out.flags() & QgsProcessingParameterDefinition.FlagHidden:
                 self.tblParameters.setHorizontalHeaderItem(
                     column, QTableWidgetItem(out.description()))
+                self.column_to_parameter_definition[column] = out.name()
                 column += 1
 
+        self.addFillRow()
+
         # Add an empty row to begin
         self.addRow()
 
         self.tblParameters.horizontalHeader().resizeSections(QHeaderView.ResizeToContents)
         self.tblParameters.verticalHeader().setSectionResizeMode(QHeaderView.ResizeToContents)
         self.tblParameters.horizontalHeader().setStretchLastSection(True)
 
+    def batchRowCount(self):
+        """
+        Returns the number of rows corresponding to execution iterations
+        """
+        return len(self.wrappers)
+
     def load(self):
         context = dataobjects.createContext()
         settings = QgsSettings()
@@ -163,7 +250,7 @@ def load(self):
             # If the user clicked on the cancel button.
             return
 
-        self.tblParameters.setRowCount(0)
+        self.tblParameters.setRowCount(1)
         try:
             for row, alg in enumerate(values):
                 self.addRow()
@@ -186,7 +273,7 @@ def load(self):
                         continue
                     if out.name() in outputs:
                         value = outputs[out.name()].strip("'")
-                        widget = self.tblParameters.cellWidget(row, column)
+                        widget = self.tblParameters.cellWidget(row + 1, column)
                         widget.setValue(value)
                     column += 1
         except TypeError:
@@ -198,7 +285,7 @@ def load(self):
     def save(self):
         toSave = []
         context = dataobjects.createContext()
-        for row in range(self.tblParameters.rowCount()):
+        for row in range(self.batchRowCount()):
             algParams = {}
             algOutputs = {}
             col = 0
@@ -222,7 +309,8 @@ def save(self):
                 value = wrapper.parameterValue()
 
                 if not param.checkValueIsAcceptable(value, context):
-                    self.parent.messageBar().pushMessage("", self.tr('Wrong or missing parameter value: {0} (row {1})').format(
+                    self.parent.messageBar().pushMessage("", self.tr(
+                        'Wrong or missing parameter value: {0} (row {1})').format(
                         param.description(), row + 1),
                         level=Qgis.Warning, duration=5)
                     return
@@ -231,15 +319,16 @@ def save(self):
             for out in alg.destinationParameterDefinitions():
                 if out.flags() & QgsProcessingParameterDefinition.FlagHidden:
                     continue
-                widget = self.tblParameters.cellWidget(row, col)
+                widget = self.tblParameters.cellWidget(row + 1, col)
                 text = widget.getValue()
                 if text.strip() != '':
                     algOutputs[out.name()] = text.strip()
                     col += 1
                 else:
-                    self.parent.messageBar().pushMessage("", self.tr('Wrong or missing output value: {0} (row {1})').format(
-                        out.description(), row + 1),
-                        level=Qgis.Warning, duration=5)
+                    self.parent.messageBar().pushMessage("",
+                                                         self.tr('Wrong or missing output value: {0} (row {1})').format(
+                                                             out.description(), row + 1),
+                                                         level=Qgis.Warning, duration=5)
                     return
             toSave.append({self.PARAMETERS: algParams, self.OUTPUTS: algOutputs})
 
@@ -258,7 +347,7 @@ def save(self):
                 json.dump(toSave, f)
 
     def setCellWrapper(self, row, column, wrapper, context):
-        self.wrappers[row][column] = wrapper
+        self.wrappers[row - 1][column] = wrapper
 
         widget_context = QgsProcessingParameterWidgetContext()
         widget_context.setProject(QgsProject.instance())
@@ -281,6 +370,12 @@ def setCellWrapper(self, row, column, wrapper, context):
 
         self.tblParameters.setCellWidget(row, column, widget)
 
+    def addFillRow(self):
+        self.tblParameters.setRowCount(1)
+        for col, name in self.column_to_parameter_definition.items():
+            param_definition = self.alg.parameterDefinition(self.column_to_parameter_definition[col])
+            self.tblParameters.setCellWidget(0, col, BatchPanelFillWidget(param_definition, col, self))
+
     def addRow(self):
         self.wrappers.append([None] * self.tblParameters.columnCount())
         self.tblParameters.setRowCount(self.tblParameters.rowCount() + 1)
@@ -319,21 +414,10 @@ def addRow(self):
             wrapper.postInitialize(list(wrappers.values()))
 
     def removeRows(self):
-        if self.tblParameters.rowCount() > 1:
+        if self.tblParameters.rowCount() > 2:
             self.wrappers.pop()
             self.tblParameters.setRowCount(self.tblParameters.rowCount() - 1)
 
-    def fillParameterValues(self, column):
-        context = dataobjects.createContext()
-
-        wrapper = self.wrappers[0][column]
-        if wrapper is None:
-            # e.g. double clicking on a destination header
-            return
-
-        for row in range(1, self.tblParameters.rowCount()):
-            self.wrappers[row][column].setParameterValue(wrapper.parameterValue(), context)
-
     def toggleAdvancedMode(self, checked):
         for column, param in enumerate(self.alg.parameterDefinitions()):
             if param.flags() & QgsProcessingParameterDefinition.FlagAdvanced: