林显影在WPF(MVVM模式)的产物。 我在我花了一个多星期没有很好的结果的情况。 请帮助我,如果你可以...下面是这种情况,根据用户的定制(用户会选择列)我要显示一组数据到数据网格。 目前即时通讯结合与一套属性数据网格的的ItemSource的的ObservableCollection。 这限制了我固定的列大小。 注:列名的数值N是列出,让用户选择。 如果它在代码中完成其背后是简单的“datagrid.columns.add()”。 任何一个都可以在那里帮助我在这种情况下。
我的XAML:
<my:DataGrid AutoGenerateColumns="False" Margin="357,121.723,82,41" Name="dataGrid3" c:DataGridExtension.Columns="{Binding ColumnCollection}" />
我的命令类:
public static class DataGridExtension
{
public static ObservableCollection<DataGridColumn> GetColumns(DependencyObject obj)
{
return (ObservableCollection<DataGridColumn>)obj.GetValue(ColumnsProperty);
}
public static void SetColumns(DependencyObject obj, ObservableCollection<DataGridColumn> value)
{
obj.SetValue(ColumnsProperty, value);
}
public static readonly DependencyProperty ColumnsProperty =
DependencyProperty.RegisterAttached("Columns", typeof(ObservableCollection<DataGridColumn>),typeof(DataGridExtension),
new UIPropertyMetadata (new ObservableCollection<DataGridColumn>(), OnDataGridColumnsPropertyChanged));
private static void OnDataGridColumnsPropertyChanged(DependencyObject d,
DependencyPropertyChangedEventArgs e)
{
if (d.GetType() == typeof(DataGrid))
{
DataGrid myGrid = d as DataGrid;
ObservableCollection<DataGridColumn> Columns = (ObservableCollection<DataGridColumn>)e.NewValue;
if (Columns != null)
{
myGrid.Columns.Clear();
if (Columns != null && Columns.Count > 0)
{
foreach (DataGridColumn dataGridColumn in Columns)
{
myGrid.Columns.Add(dataGridColumn);
}
}
Columns.CollectionChanged += delegate(object sender, NotifyCollectionChangedEventArgs args)
{
if (args.NewItems != null)
{
//foreach (DataGridColumn column in args.NewItems.Cast<DataGridColumn>())
//{
// myGrid.Columns.Add(column);
//}
}
if (args.OldItems != null)
{
//foreach (DataGridColumn column in args.OldItems.Cast<DataGridColumn>())
//{
// myGrid.Columns.Remove(column);
//}
}
};
}
}
}
}
和我的视图模型属性:
private ObservableCollection<DataGridColumn> _columnCollection = new ObservableCollection<DataGridColumn>();
public ObservableCollection<DataGridColumn> ColumnCollection
{
get
{
return this._columnCollection;
}
set
{
_columnCollection = value;
base.OnPropertyChanged("ColumnCollection");
//Error
//base.OnPropertyChanged<ObservableCollection<DataGridColumn>>(() => this.ColumnCollection);
}
}
感谢您的努力家伙的......终于我已经找到了解决办法....
这里的..(全WPF MVVM)
在我的命令文件:
public class DataGridColumnsBehavior
{
public static readonly DependencyProperty BindableColumnsProperty =
DependencyProperty.RegisterAttached("BindableColumns",
typeof(ObservableCollection<DataGridColumn>),
typeof(DataGridColumnsBehavior),
new UIPropertyMetadata(null, BindableColumnsPropertyChanged));
private static void BindableColumnsPropertyChanged(DependencyObject source, DependencyPropertyChangedEventArgs e)
{
DataGrid dataGrid = source as DataGrid;
ObservableCollection<DataGridColumn> columns = e.NewValue as ObservableCollection<DataGridColumn>;
dataGrid.Columns.Clear();
if (columns == null)
{
return;
}
foreach (DataGridColumn column in columns)
{
dataGrid.Columns.Add(column);
}
columns.CollectionChanged += (sender, e2) =>
{
NotifyCollectionChangedEventArgs ne = e2 as NotifyCollectionChangedEventArgs;
if (ne.Action == NotifyCollectionChangedAction.Reset)
{
dataGrid.Columns.Clear();
if (ne.NewItems != null)
{
foreach (DataGridColumn column in ne.NewItems)
{
dataGrid.Columns.Add(column);
}
}
}
else if (ne.Action == NotifyCollectionChangedAction.Add)
{
if (ne.NewItems != null)
{
foreach (DataGridColumn column in ne.NewItems)
{
dataGrid.Columns.Add(column);
}
}
}
else if (ne.Action == NotifyCollectionChangedAction.Move)
{
dataGrid.Columns.Move(ne.OldStartingIndex, ne.NewStartingIndex);
}
else if (ne.Action == NotifyCollectionChangedAction.Remove)
{
if (ne.OldItems != null)
{
foreach (DataGridColumn column in ne.OldItems)
{
dataGrid.Columns.Remove(column);
}
}
}
else if (ne.Action == NotifyCollectionChangedAction.Replace)
{
dataGrid.Columns[ne.NewStartingIndex] = ne.NewItems[0] as DataGridColumn;
}
};
}
public static void SetBindableColumns(DependencyObject element, ObservableCollection<DataGridColumn> value)
{
element.SetValue(BindableColumnsProperty, value);
}
public static ObservableCollection<DataGridColumn> GetBindableColumns(DependencyObject element)
{
return (ObservableCollection<DataGridColumn>)element.GetValue(BindableColumnsProperty);
}
}
在我的XAML:
<my:DataGrid AutoGenerateColumns="False" Margin="357,121.723,82,41" Name="dataGrid3" ItemsSource="{Binding Path=Datatable}" c:DataGridColumnsBehavior.BindableColumns="{Binding ColumnCollection}" />
和finaly在我的视图模型:
private ObservableCollection<DataGridColumn> _columnCollection = new ObservableCollection<DataGridColumn>();
public ObservableCollection<DataGridColumn> ColumnCollection
{
get
{
return this._columnCollection;
}
set
{
_columnCollection = value;
base.OnPropertyChanged("ColumnCollection");
//Error
//base.OnPropertyChanged<ObservableCollection<DataGridColumn>>(() => this.ColumnCollection);
}
}
private DataTable _datatable = new DataTable();
public DataTable Datatable
{
get
{
return _datatable;
}
set
{
if (_datatable != value)
{
_datatable = value;
}
base.OnPropertyChanged("Datatable");
}
}
在我的构造函数:
public MainViewModel()
{
Datatable.Columns.Add("Name",typeof(string));
Datatable.Columns.Add("Color", typeof(string));
Datatable.Columns.Add("Phone", typeof(string));
Datatable.Rows.Add("Vinoth", "#00FF00", "456345654");
Datatable.Rows.Add("lkjasdgl", "Blue", "45654");
Datatable.Rows.Add("Vinoth", "#FF0000", "456456");
System.Windows.Data.Binding bindings = new System.Windows.Data.Binding("Name");
System.Windows.Data.Binding bindings1 = new System.Windows.Data.Binding("Phone");
System.Windows.Data.Binding bindings2 = new System.Windows.Data.Binding("Color");
DataGridTextColumn s = new DataGridTextColumn();
s.Header = "Name";
s.Binding = bindings;
DataGridTextColumn s1 = new DataGridTextColumn();
s1.Header = "Phone";
s1.Binding = bindings1;
DataGridTextColumn s2 = new DataGridTextColumn();
s2.Header = "Color";
s2.Binding = bindings2;
FrameworkElementFactory textblock = new FrameworkElementFactory(typeof(TextBlock));
textblock.Name = "text";
System.Windows.Data.Binding prodID = new System.Windows.Data.Binding("Name");
System.Windows.Data.Binding color = new System.Windows.Data.Binding("Color");
textblock.SetBinding(TextBlock.TextProperty, prodID);
textblock.SetValue(TextBlock.TextWrappingProperty, TextWrapping.Wrap);
//textblock.SetValue(TextBlock.BackgroundProperty, color);
textblock.SetValue(TextBlock.NameProperty, "textblock");
//FrameworkElementFactory border = new FrameworkElementFactory(typeof(Border));
//border.SetValue(Border.NameProperty, "border");
//border.AppendChild(textblock);
DataTrigger t = new DataTrigger();
t.Binding = new System.Windows.Data.Binding { Path = new PropertyPath("Name"), Converter = new EnableConverter(), ConverterParameter ="Phone" };
t.Value = 1;
t.Setters.Add(new Setter(TextBlock.BackgroundProperty, Brushes.LightGreen, textblock.Name));
t.Setters.Add(new Setter(TextBlock.ToolTipProperty, bindings, textblock.Name));
DataTrigger t1 = new DataTrigger();
t1.Binding = new System.Windows.Data.Binding { Path = new PropertyPath("Name"), Converter = new EnableConverter(), ConverterParameter = "Phone" };
t1.Value = 2;
t1.Setters.Add(new Setter(TextBlock.BackgroundProperty, Brushes.LightYellow, textblock.Name));
t1.Setters.Add(new Setter(TextBlock.ToolTipProperty, bindings, textblock.Name));
DataTemplate d = new DataTemplate();
d.VisualTree = textblock;
d.Triggers.Add(t);
d.Triggers.Add(t1);
DataGridTemplateColumn s3 = new DataGridTemplateColumn();
s3.Header = "Name 1";
s3.CellTemplate = d;
s3.Width = 140;
ColumnCollection.Add(s);
ColumnCollection.Add(s1);
ColumnCollection.Add(s2);
ColumnCollection.Add(s3);
}
我想延续之前的例子(回答)订阅和取消订阅事件CollectionChanged的能力。
行为 (加上System.Windows.Interactivity参考):
public class ColumnsBindingBehaviour : Behavior<DataGrid>
{
public ObservableCollection<DataGridColumn> Columns
{
get { return (ObservableCollection<DataGridColumn>) base.GetValue(ColumnsProperty); }
set { base.SetValue(ColumnsProperty, value); }
}
public static readonly DependencyProperty ColumnsProperty = DependencyProperty.Register("Columns",
typeof(ObservableCollection<DataGridColumn>), typeof(ColumnsBindingBehaviour),
new PropertyMetadata(OnDataGridColumnsPropertyChanged));
private static void OnDataGridColumnsPropertyChanged(DependencyObject source, DependencyPropertyChangedEventArgs e)
{
var context = source as ColumnsBindingBehaviour;
var oldItems = e.OldValue as ObservableCollection<DataGridColumn>;
if (oldItems != null)
{
foreach (var one in oldItems)
context._datagridColumns.Remove(one);
oldItems.CollectionChanged -= context.collectionChanged;
}
var newItems = e.NewValue as ObservableCollection<DataGridColumn>;
if (newItems != null)
{
foreach (var one in newItems)
context._datagridColumns.Add(one);
newItems.CollectionChanged += context.collectionChanged;
}
}
private ObservableCollection<DataGridColumn> _datagridColumns;
protected override void OnAttached()
{
base.OnAttached();
this._datagridColumns = AssociatedObject.Columns;
}
private void collectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
if (e.NewItems != null)
foreach (DataGridColumn one in e.NewItems)
_datagridColumns.Add(one);
break;
case NotifyCollectionChangedAction.Remove:
if (e.OldItems != null)
foreach (DataGridColumn one in e.OldItems)
_datagridColumns.Remove(one);
break;
case NotifyCollectionChangedAction.Move:
_datagridColumns.Move(e.OldStartingIndex, e.NewStartingIndex);
break;
case NotifyCollectionChangedAction.Reset:
_datagridColumns.Clear();
if (e.NewItems != null)
foreach (DataGridColumn one in e.NewItems)
_datagridColumns.Add(one);
break;
}
}
}
查看 :
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:loc="clr-namespace:WpfApplication1"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
Title="MainWindow" Height="350" Width="525">
<Grid>
<DataGrid x:Name="_dataGrid">
<DataGrid.Columns>
<DataGridTextColumn Header="Test" />
</DataGrid.Columns>
<i:Interaction.Behaviors>
<loc:ColumnsBindingBehaviour Columns="{Binding DataGridColumns}"/>
</i:Interaction.Behaviors>
</DataGrid>
</Grid>
视图模型:
private ObservableCollection<DataGridColumn> _dataGridColumns;
public ObservableCollection<DataGridColumn> DataGridColumns
{
get
{
if (_dataGridColumns == null)
_dataGridColumns = new ObservableCollection<DataGridColumn>()
{
new DataGridTextColumn()
{
Header = "Column1"
}
};
return _dataGridColumns;
}
set
{
_dataGridColumns = value;
OnPropertyChanged("DataGridColumns");
}
}