我正在使用
ObservableCollection<>
实现 DataGrid 分页。
第一次正确显示10条记录。当点击Next
按钮时,没有显示第二页。当我调试时,我发现当我设置 currentpagenumber 时, PropertyChanged
事件没有触发。
我的代码是
ObservableCollection<RiskSettings> riskCollection = new ObservableCollection<RiskSettings>();
private ObservableCollection<ObservableCollection<RiskSettings>> Pages;
private ObservableCollection<RiskSettings> _ItemsSource;
private ObservableCollection<RiskSettings> _CurrentPage;
public RiskAlert()
{
InitializeComponent();
GeneratePages();
}
private void GeneratePages()
{
if (riskCollection.Count > 0)
{
PageCount = (int)Math.Ceiling(riskCollection.Count / (double)ItemsPerPage);
Pages = new ObservableCollection<ObservableCollection<RiskSettings>>();
for (int i = 0; i < PageCount; i++)
{
ObservableCollection<RiskSettings> page = new ObservableCollection<RiskSettings>();
for (int j = 0; j < ItemsPerPage; j++)
{
if (i * ItemsPerPage + j > riskCollection.Count - 1) break;
page.Add(riskCollection[i * ItemsPerPage + j]);
}
Pages.Add(page);
}
this.CurrentPage = Pages[0];
this.CurrentPageNumber = 1;
}
}
public int CurrentPageNumber
{
get { return _CurrentPageNumber; }
set
{
_CurrentPageNumber = value;
//if (PropertyChanged != null)
this.OnPropertyChanged(new PropertyChangedEventArgs("CurrentPageNumber"));
}
}
public ObservableCollection<RiskSettings> Collection
{
get
{
return riskCollection;
}
set
{
riskCollection = value;
GeneratePages();
}
}
public ObservableCollection<RiskSettings> CurrentPage
{
get { return _CurrentPage; }
set
{
_CurrentPage = value;
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs("CurrentPage"));
}
}
public int CurrentPageNumber
{
get { return _CurrentPageNumber; }
set
{
_CurrentPageNumber = value;
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs("CurrentPageNumber"));
}
}
public int ItemsPerPage
{
get { return (int)GetValue(ItemsPerPageProperty); }
set { SetValue(ItemsPerPageProperty, value); }
}
public static readonly DependencyProperty ItemsPerPageProperty = DependencyProperty.Register("ItemsPerPage", typeof(int), typeof(RiskAlert), new UIPropertyMetadata(20));
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
#endregion
我收集了riskCollection中的所有数据。我的DataGrid名称是grdRiskAlerts 我绑定为
GeneratePages();
this.ItemsSource = riskCollection;
grdRiskAlerts.ItemsSource = CurrentPage;
txtTotalRecs.Text = "Total : " + riskCollection.Count();
//txtDispRecs.Text = CurrentPage.Count().ToString();
txtNumOfPages.Text = this.CurrentPageNumber.ToString();
totalRecords = riskCollection.Count();
if (pageSize <= totalRecords)
{
if (totalRecords > 0)
txtDispRecs.Text = "Displaying 1 to " + CurrentPage.Count();
else
txtDispRecs.Text = "Displaying 0 to " + CurrentPage.Count();
}
对于这个分页的东西,我遵循了谷歌的一个例子 我不知道为什么 propertychanged 事件没有触发。
有人可以帮忙吗?
拉姆基。
明显的问题是您直接设置值而不是更新绑定源。看看您是否将某些源绑定到属性,然后手动更改该属性,您会破坏绑定,这就是属性更改不触发的原因。