我一直在尝试在WPF MVVM项目中使用动态列创建一个可编辑的DataGrid.动态列将是相同的类型,即：decimal.
目的是收集具有无限数量部门的商店的部门总数.我试着在下面演示它.
Day Dept1 Dept2 Dept3... TotalOfDepartments CashTotal CreditTotal
=====================================================================
1 100 200 50 350 50 300
2 75 100 0 175 25 150
因此,有许多商店有无限期的部门,我的目标是收集月份
我想制作部门,CashTotal& CreditTotal Columns可编辑.我尝试了几种方法：
> populate dynamic datagrid column and binding with editable using mVVm
> Populating a DataGrid with Dynamic Columns in a Silverlight Application using MVVM
> How do I bind a WPF DataGrid to a variable number of columns?
这是我最后一次尝试的最后一次尝试.如下：
模型：
public class DailyRevenues
{
public int ShopId { get; set; }
public int Day { get; set; }
public ObservableCollection<Department> DepartmentList { get; set; }
public DailyRevenues()
{
this.DepartmentList = new ObservableCollection<Department>();
}
}
public class Department
{
public string Name { get; set; }
private decimal total;
public decimal Total
{
get { return total; }
set { total = value; }
}
}
视图模型：
public class DataItemViewModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public DataItemViewModel()
{
this.MonthlyRevenues = new ObservableCollection<DailyRevenues>();
var d1 = new DailyRevenues() { ShopId = 1, Day = 1 };
d1.DepartmentList.Add(new Department() { Name = "Deapartment1", Total = 100 });
d1.DepartmentList.Add(new Department() { Name = "Deapartment2", Total = 200 });
var d2 = new DailyRevenues() { ShopId = 1, Day = 2 };
d2.DepartmentList.Add(new Department() { Name = "Deapartment1", Total = 75 });
d2.DepartmentList.Add(new Department() { Name = "Deapartment2", Total = 150 });
d2.DepartmentList.Add(new Department() { Name = "Deapartment3", Total = 100 });
this.MonthlyRevenues.Add(d1);
this.MonthlyRevenues.Add(d2);
}
private ObservableCollection<DailyRevenues> monthlyRevenues;
public ObservableCollection<DailyRevenues> MonthlyRevenues
{
get { return monthlyRevenues; }
set
{
if (monthlyRevenues != value)
{
monthlyRevenues = value;
OnPropertyChanged(nameof(MonthlyRevenues));
}
}
}
private void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
和XAML：
<DataGrid ItemsSource="{Binding MonthlyRevenues}" AutoGenerateColumns="False" >
<DataGrid.Columns>
<DataGridTextColumn Header="Day" Binding="{Binding Path=Day}" />
<DataGridTextColumn Header="{Binding Path=MonthlyRevenues[0].DepartmentList[0].Name}" Binding="{Binding Path=DepartmentList[0].Total, Mode=TwoWay}" />
<DataGridTextColumn Header="{Binding Path=DepartmentList[1].Name}" Binding="{Binding Path=DepartmentList[1].Total, Mode=TwoWay}" />
<DataGridTextColumn Header="Department Total"/>
<DataGridTextColumn Header="Cash Total" />
<DataGridTextColumn Header="Credit Total" />
</DataGrid.Columns>
</DataGrid>
不幸的是,在最后一次尝试使用XAML上的索引器对动态列没有帮助,我找不到以任何其他方式绑定它们的方法.
更多信息：上面的datagrid(和数据演示)属于shop1,我想在窗口/用户控件上收集它的部门的月收入.每个商店在整个月内都有相同数量的部门,但这并不意味着每个部门每天都应该有收入,它可以是零.该部门可能会在任何一天关闭,因此当天不会产生任何收入. Shop2可能在同一个月有完全不同的部门,所以我不会在同一个屏幕上处理所有商店.
编辑1：有关添加的场景的更多信息.
解决方法:
你可以采取许多不同的方法,每种方法都有优点和缺点.根据您对问题的更完整描述,我选择了自定义类型描述符方法.
在这里,我们为每日收入类添加一个自定义类型描述符…
public class DailyRevenues : ICustomTypeDescriptor
{
public int ShopId { get; set; }
public int Day { get; set; }
public ObservableCollection<Department> DepartmentList { get; set; }
public DailyRevenues()
{
this.DepartmentList = new ObservableCollection<Department>();
}
public decimal TotalOfDepartments { get; }
public decimal CashTotal { get; }
public decimal CreditTotal { get; }
public AttributeCollection GetAttributes()
{
return new AttributeCollection();
}
public string GetClassName()
{
return "DailyRevenues";
}
public string GetComponentName()
{
return "";
}
public TypeConverter GetConverter()
{
return null;
}
public EventDescriptor GetDefaultEvent()
{
return null;
}
public PropertyDescriptor GetDefaultProperty()
{
return null;
}
public object GetEditor(Type editorBaseType)
{
return null;
}
public EventDescriptorCollection GetEvents()
{
return null;
}
public EventDescriptorCollection GetEvents(Attribute[] attributes)
{
return null;
}
public PropertyDescriptorCollection GetProperties()
{
PropertyDescriptorCollection pdc0 = TypeDescriptor.GetProperties(typeof(DailyRevenues));
List<PropertyDescriptor> pdList = new List<PropertyDescriptor>();
pdList.Add(pdc0["Day"]);
for (int i = 0; i < DepartmentList.Count; ++i)
{
pdList.Add(new DailyRevenuesProperty(DepartmentList[i].Name, i));
}
pdList.Add(pdc0["TotalOfDepartments"]);
pdList.Add(pdc0["CashTotal"]);
pdList.Add(pdc0["CreditTotal"]);
return new PropertyDescriptorCollection(pdList.ToArray());
}
public PropertyDescriptorCollection GetProperties(Attribute[] attributes)
{
return GetProperties();
}
public object GetPropertyOwner(PropertyDescriptor pd)
{
return this;
}
}
自定义类型描述符允许我们“展平”数据结构.随着部门数量的变化,对象上的属性数量也会发生变化.这需要每日收入等级的自定义属性描述符…
public class DailyRevenuesProperty : PropertyDescriptor
{
int _index;
public DailyRevenuesProperty(string name, int index)
: base(name, new Attribute[0])
{
_index = index;
}
public override Type ComponentType
{
get
{
return typeof(DailyRevenues);
}
}
public override bool IsReadOnly
{
get
{
return false;
}
}
public override Type PropertyType
{
get
{
return typeof(decimal);
}
}
public override bool CanResetValue(object component)
{
return false;
}
public override object GetValue(object component)
{
DailyRevenues dr = component as DailyRevenues;
if(dr != null && _index >= 0 && _index < dr.DepartmentList.Count)
{
return dr.DepartmentList[_index].Total;
}
else
{
return (decimal)0;
}
}
public override void ResetValue(object component)
{
}
public override void SetValue(object component, object value)
{
DailyRevenues dr = component as DailyRevenues;
if (dr != null && _index >= 0 && _index < dr.DepartmentList.Count && value is decimal)
{
dr.DepartmentList[_index].Total = (decimal)value;
}
}
public override bool ShouldSerializeValue(object component)
{
return false;
}
}
现在我们需要一个打字列表.这取代了可观察的集合.
public class MonthlyRevenues : ObservableCollection<DailyRevenues>, ITypedList
{
public PropertyDescriptorCollection GetItemProperties(PropertyDescriptor[] listAccessors)
{
if(Count > 0)
{
return TypeDescriptor.GetProperties(this[0]);
}
else
{
return TypeDescriptor.GetProperties(typeof(DailyRevenues));
}
}
public string GetListName(PropertyDescriptor[] listAccessors)
{
return "Monthly Revenues";
}
}
自动生成列时,数据网格会检查项集合是否为类型列表.如果是,则数据网格查询键入列表上的属性.
最后要总结一下,这里是数据网格……
<DataGrid ItemsSource="{Binding MonthlyRevenues}" AutoGenerateColumns="true" />
这就是结果网格……
这种方法有许多限制.首先,我依靠数据网格自动生成列.如果我想在标题文本中添加空格之类的东西,我需要做更多的事情.其次,我指望部门名称是有效的属性名称,并且不会与日常收入类别中的其他属性发生冲突.如果没有,那么我将需要做更多的事情.等等.