问题
I want to create a basic user control with a style programmatically.
In this style I want to add a Grid
(no problem), but I can't add column definitions to this grid.
My example code is
ControlTemplate templ = new ControlTemplate();
FrameworkElementFactory mainPanel = new FrameworkElementFactory(typeof(DockPanel));
mainPanel.SetValue(DockPanel.LastChildFillProperty, true);
FrameworkElementFactory headerPanel = new FrameworkElementFactory(typeof(StackPanel));
headerPanel.SetValue(StackPanel.OrientationProperty, Orientation.Horizontal);
headerPanel.SetValue(DockPanel.DockProperty, Dock.Top);
mainPanel.AppendChild(headerPanel);
FrameworkElementFactory headerImg = new FrameworkElementFactory(typeof(Image));
headerImg.SetValue(Image.MarginProperty, new Thickness(5));
headerImg.SetValue(Image.HeightProperty, 32d);
headerImg.SetBinding(Image.SourceProperty, new Binding("ElementImage") { RelativeSource = new RelativeSource(RelativeSourceMode.TemplatedParent) });
headerPanel.AppendChild(headerImg);
FrameworkElementFactory headerTitle = new FrameworkElementFactory(typeof(TextBlock));
headerTitle.SetValue(TextBlock.FontSizeProperty, 16d);
headerTitle.SetValue(TextBlock.VerticalAlignmentProperty, VerticalAlignment.Center);
headerTitle.SetBinding(TextBlock.TextProperty, new Binding("Title") { RelativeSource = new RelativeSource(RelativeSourceMode.TemplatedParent) });
headerPanel.AppendChild(headerTitle);
FrameworkElementFactory mainGrid = new FrameworkElementFactory(typeof(Grid));
FrameworkElementFactory c1 = new FrameworkElementFactory(typeof(ColumnDefinition));
c1.SetValue(ColumnDefinition.WidthProperty, new GridLength(1, GridUnitType.Star));
FrameworkElementFactory c2 = new FrameworkElementFactory(typeof(ColumnDefinition));
c2.SetValue(ColumnDefinition.WidthProperty, new GridLength(1, GridUnitType.Auto));
FrameworkElementFactory c3 = new FrameworkElementFactory(typeof(ColumnDefinition));
c3.SetValue(ColumnDefinition.WidthProperty, new GridLength(3, GridUnitType.Star));
FrameworkElementFactory colDefinitions = new FrameworkElementFactory(typeof(ColumnDefinitionCollection));
colDefinitions.AppendChild(c1);
colDefinitions.AppendChild(c2);
colDefinitions.AppendChild(c3);
mainGrid.AppendChild(colDefinitions);
mainPanel.AppendChild(mainGrid);
FrameworkElementFactory content = new FrameworkElementFactory(typeof(ContentPresenter));
content.SetBinding(ContentPresenter.ContentProperty, new Binding() { RelativeSource = new RelativeSource(RelativeSourceMode.TemplatedParent), Path = new PropertyPath("Content") });
mainGrid.AppendChild(content);
templ.VisualTree = mainPanel;
Style mainStyle = new Style();
mainStyle.Setters.Add(new Setter(UserControl.TemplateProperty, templ));
this.Style = mainStyle;
But the creation of FrameworkElementFactory
with type ColumnDefinitionCollection
will throw an exception "'ColumnDefinitionCollection' type must derive from FrameworkElement, FrameworkContentElement, or Visual3D."
Who can help me?
回答1:
FrameworkElementFactory has some custom logic for handling the ColumnDefinitions and RowDefinitions in a Grid. For those values, you treat them like children in the factory tree, for example:
FrameworkElementFactory gridFactory = new FrameworkElementFactory(typeof(Grid));
var column1 = new FrameworkElementFactory(typeof(ColumnDefinition));
column1.SetValue(ColumnDefinition.WidthProperty, new GridLength(1, GridUnitType.Auto));
var column2 = new FrameworkElementFactory(typeof(ColumnDefinition));
column2.SetValue(ColumnDefinition.WidthProperty, new GridLength(1, GridUnitType.Star));
gridFactory.AppendChild(column1);
gridFactory.AppendChild(column2);
回答2:
you can simply add column definitions like this
XAML Code:
<Grid.ColumnDefinitions>
<ColumnDefinition Height="50"/>
<ColumnDefinition Height="100"/>
<ColumnDefinition Height="*"/>
</Grid.ColumnDefinitions>
C# Code:
ColumnDefinition c = new ColumnDefinition();
c.Width = new GridLength(50, GridUnitType.Pixel);
ColumnDefinition c1 = new ColumnDefinition();
c1.Width = new GridLength(100, GridUnitType.Pixel);
ColumnDefinition c2 = new ColumnDefinition();
c2.Width = new GridLength(0, GridUnitType.Star);
grMain.ColumnDefinitions.Add(c);
grMain.ColumnDefinitions.Add(c1);
grMain.ColumnDefinitions.Add(c2);
for more check here
回答3:
//create grid
var grid = new FrameworkElementFactory(typeof(Grid));
// assign template to grid
CellControlTemplate.VisualTree = grid;
// define grid's rows
var r = new FrameworkElementFactory(typeof(RowDefinition));
grid.AppendChild(r);
// define grid's columns
var c = new FrameworkElementFactory(typeof(ColumnDefinition));
grid.AppendChild(c);
c = new FrameworkElementFactory(typeof(ColumnDefinition));
c.SetValue(ColumnDefinition.WidthProperty, GridLength.Auto);
grid.AppendChild(c);
c = new FrameworkElementFactory(typeof(ColumnDefinition));
c.SetValue(ColumnDefinition.WidthProperty, GridLength.Auto);
grid.AppendChild(c);
回答4:
You just need to change the last part of your code. See below,
Original Code:
colDefinitions.AppendChild(c1);
colDefinitions.AppendChild(c2);
colDefinitions.AppendChild(c3);
mainGrid.AppendChild(colDefinitions);
New Code:
mainGrid.AppendChild(c1);
mainGrid.AppendChild(c2);
mainGrid.AppendChild(c3);
来源:https://stackoverflow.com/questions/4517170/create-a-grid-in-wpf-as-template-programmatically