ObservableCollection not updating
本文关键字：updating not ObservableCollection | 更新日期: 2023-09-27 18:12:50
我觉得我真的很接近让这个工作。我有一个日历，我希望用户能够从组合框中选择一个月，并显示该日期的日历。现在，无论我从组合框中选择什么，都不会显示任何内容。我可以得到它的工作，通过使用一个列表框和一个按钮事件，但它不是真正的更新，它只是清除和显示新的月份选择。这不是正确的做法。我花了很多时间在这上面，如果有人能看看，给我一些建议，我真的很感激。
——模型类 ---------
public partial class SchedulePage : Page, INotifyPropertyChanged
{
public int pick2;
public event PropertyChangedEventHandler PropertyChanged;
MainWindow _parentForm;
public int pick;
Schedule sched = new Schedule();
static GregorianCalendar _gc = new GregorianCalendar();
public SchedulePage(MainWindow parentForm)
{
InitializeComponent();
// this.PropertyChanged += comboMonth_SelectionChanged;
pick = Convert.ToInt32(comboMonth.SelectedItem);
_parentForm = parentForm;
}
public void NotifyPropertyChanged(String info)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(info));
}
}
private int _nameofmonth ;
public int NameofMonth
{
get
{
return this._nameofmonth;
}
set
{
if (value != this._nameofmonth)
{
this._nameofmonth = value;
NotifyPropertyChanged("NameofMonth");
}
}
}
// void TheViewModel_PropertyChanged(object src, PropertyChangedEventArgs e)
private void comboMonth_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
//{
// if (e.PropertyName == "NameofMonth")
// {
//var date = new DateTime(2011, 11, 1);
//makeCalender(date);
_parentForm.bindings.schedule.Clear();
var t = new List<Schedule>();
DateTime curr = DateTime.Now;
int jeez = comboMonth.SelectedIndex+1;
// comboMonth.Items.Add(curr.Month);
DateTime newcurr = new DateTime(2011, NameofMonth+1, 1);
// pickdate = datePickercal.SelectedDate;
// DateTime newcurr = new DateTime(curr.Year, curr.Month, 1);
var cal = System.Globalization.DateTimeFormatInfo.CurrentInfo.Calendar;
var ms = cal.GetWeekOfYear(new DateTime(newcurr.Year, newcurr.Month, 1), System.Globalization.CalendarWeekRule.FirstDay, System.DayOfWeek.Sunday);
for (var i = 1; newcurr.Month == NameofMonth+1; newcurr = newcurr.AddDays(1))
{
var month_week = (newcurr.Day / 7);
sched.MonthWeek = newcurr.GetWeekOfMonth().ToString();
sched.Month = newcurr.Month.ToString();
sched.Year = newcurr.Year.ToString();
sched.day = newcurr.Day.ToString();
sched.WeekOfYear = cal.GetWeekOfYear(newcurr, System.Globalization.CalendarWeekRule.FirstDay, DayOfWeek.Sunday).ToString();
sched.dayofweek = newcurr.DayOfWeek.ToString();
t.Add(sched);
_parentForm.bindings.schedule.Add(new Schedule { WeekNo = newcurr.GetWeekOfMonth() - 1, WeekDay = (int)newcurr.DayOfWeek, day = newcurr.Day.ToString() });
}
lblDate.Content = (newcurr.Month - 1) + "/" + newcurr.Year;
//testGrid.ItemsSource = t;
comboMonth.DataContext = _parentForm.bindings;
DataContext = _parentForm.bindings;
// }
}
----部分XAML------
<ComboBox SelectedIndex="{Binding NameofMonth}" Grid.ColumnSpan="2" Height="23" HorizontalAlignment="Left" Margin="6,0,0,0" Name="comboMonth" VerticalAlignment="Top" Width="120" SelectionChanged="comboMonth_SelectionChanged">
<ComboBoxItem Content="1" IsSelected="False" />
<ComboBoxItem Content="2" />
<ComboBoxItem Content="3" />
<ComboBoxItem Content="4" />
<ComboBoxItem Content="5" />
<ComboBoxItem Content="6" />
<ComboBoxItem Content="7" />
<ComboBoxItem Content="8" />
<ComboBoxItem Content="9" />
<ComboBoxItem Content="10" />
<ComboBoxItem Content="11" IsSelected="False" />
<ComboBoxItem Content="12" />
</ComboBox>
你需要让你的poco类在你的ObservableCollection中使用实现INotifyChanged
的例子:
<viewModels:LocationsViewModel x:Key="viewModel" />
.
.
.
<ListView
DataContext="{StaticResource viewModel}"
ItemsSource="{Binding Locations}"
IsItemClickEnabled="True"
ItemClick="GroupSection_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}" Margin="0,0,10,0" Style="{ThemeResource ListViewItemTextBlockStyle}" />
<TextBlock Text="{Binding Latitude, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Style="{ThemeResource ListViewItemTextBlockStyle}" Margin="0,0,5,0"/>
<TextBlock Text="{Binding Longitude, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Style="{ThemeResource ListViewItemTextBlockStyle}" Margin="5,0,0,0" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
public class LocationViewModel : BaseViewModel
{
ObservableCollection<Location> _locations = new ObservableCollection<Location>();
public ObservableCollection<Location> Locations
{
get
{
return _locations;
}
set
{
if (_locations != value)
{
_locations = value;
OnNotifyPropertyChanged();
}
}
}
}
public class Location : BaseViewModel
{
int _locationId = 0;
public int LocationId
{
get
{
return _locationId;
}
set
{
if (_locationId != value)
{
_locationId = value;
OnNotifyPropertyChanged();
}
}
}
string _name = null;
public string Name
{
get
{
return _name;
}
set
{
if (_name != value)
{
_name = value;
OnNotifyPropertyChanged();
}
}
}
float _latitude = 0;
public float Latitude
{
get
{
return _latitude;
}
set
{
if (_latitude != value)
{
_latitude = value;
OnNotifyPropertyChanged();
}
}
}
float _longitude = 0;
public float Longitude
{
get
{
return _longitude;
}
set
{
if (_longitude != value)
{
_longitude = value;
OnNotifyPropertyChanged();
}
}
}
}
public class BaseViewModel : INotifyPropertyChanged
{
#region Events
public event PropertyChangedEventHandler PropertyChanged;
#endregion
protected void OnNotifyPropertyChanged([CallerMemberName] string memberName = "")
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(memberName));
}
}
}