以编程方式在WPF中创建网格作为模板

Question

我想以编程方式创建一个带有样式的基本用户控件。 在这种风格中我想添加一个Grid （没问题），但是我不能在这个网格中添加列定义。

我的示例代码是

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;

但是，使用ColumnDefinitionCollection类型创建FrameworkElementFactory将抛出异常"'ColumnDefinitionCollection' type must derive from FrameworkElement, FrameworkContentElement, or Visual3D."

谁能帮我？

Answer 1

FrameworkElementFactory有一些自定义逻辑，用于处理Grid中的ColumnDefinitions和RowDefinitions。 对于这些值，您可以将它们视为工厂树中的子项，例如：

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);

Answer 2

你可以简单地添加这样的列定义

XAML代码：

<Grid.ColumnDefinitions>
<ColumnDefinition Height="50"/>
<ColumnDefinition Height="100"/>
<ColumnDefinition Height="*"/>
</Grid.ColumnDefinitions>

C＃代码：

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);

更多检查在这里

Answer 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);

Answer 4

您只需要更改代码的最后一部分。 见下文，

原始代码：

        colDefinitions.AppendChild(c1);
        colDefinitions.AppendChild(c2);
        colDefinitions.AppendChild(c3);
        mainGrid.AppendChild(colDefinitions);

新守则：

        mainGrid.AppendChild(c1);
        mainGrid.AppendChild(c2);
        mainGrid.AppendChild(c3);