[processing] Add a setParameters method to AlgorithmDialog

Allows pre-populating the dialog with non-default parameter
values.

python/plugins/processing/gui/AlgorithmDialog.py

@@ -80,6 +80,9 @@ class AlgorithmDialog(QgsProcessingAlgorithmDialogBase):
         dlg.show()
         dlg.exec_()
 
+    def setParameters(self, parameters):
+        self.mainWidget().setParameters(parameters)
+
     def getParameterValues(self):
         parameters = {}
 

python/plugins/processing/gui/DestinationSelectionPanel.py

@@ -266,6 +266,12 @@ class DestinationSelectionPanel(BASE, WIDGET):
             self.leText.setText(QDir.toNativeSeparators(dirName))
             settings.setValue('/Processing/LastOutputPath', dirName)
 
+    def setValue(self, value):
+        if value == 'memory:':
+            self.saveToTemporary()
+        else:
+            self.leText.setText(value)
+
     def getValue(self):
         key = None
         if self.use_temporary and isinstance(self.parameter, QgsProcessingParameterFeatureSink):

python/plugins/processing/gui/ParametersPanel.py

@@ -181,6 +181,21 @@ class ParametersPanel(BASE, WIDGET):
         for wrapper in list(self.wrappers.values()):
             wrapper.postInitialize(list(self.wrappers.values()))
 
+    def setParameters(self, parameters):
+        for param in self.alg.parameterDefinitions():
+            if param.flags() & QgsProcessingParameterDefinition.FlagHidden:
+                continue
+
+            if not param.name() in parameters:
+                continue
+
+            if not param.isDestination():
+                wrapper = self.wrappers[param.name()]
+                wrapper.setValue(parameters[param.name()])
+            else:
+                dest_widget = self.outputWidgets[param.name()]
+                dest_widget.setValue(parameters[param.name()])
+
     def buttonToggled(self, value):
         if value:
             sender = self.sender()