Event handling with LongListSelector and list item with checkbox

Question

I've a LongListSelector with the following item template:

    <DataTemplate x:Key="stopItemTemplate">
        <Grid Margin="{StaticResource PhoneTouchTargetOverhang}">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <CheckBox VerticalAlignment="Top" HorizontalAlignment="Left" IsChecked="{Binding Checked}" Click="AlarmActivationClicked" />
            <StackPanel Grid.Column="1" VerticalAlignment="Top">
                <TextBlock Text="{Binding Stop.Name}" Style="{StaticResource PhoneTextLargeStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}" TextWrapping="Wrap" Margin="12,-12,12,6"/>
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="Distanz:" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}" Width="120"/>
                    <TextBlock Text="{Binding Distance, Converter={StaticResource MyStringFormatConverter}, ConverterParameter=:1000:\{0:0.0\} km}" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}"/>
                </StackPanel>
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="Alarm:" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}" Width="120"/>
                    <TextBlock Text="{Binding Alarm, Converter={StaticResource MyBooleanStringConverter}}" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}"/>
                </StackPanel>
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="Vibration:" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}" Width="120"/>
                    <TextBlock Text="{Binding Vibration, Converter={StaticResource MyBooleanStringConverter}}" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}"/>
                </StackPanel>
            </StackPanel>
        </Grid>
    </DataTemplate>

And used as followed:

<controls:PivotItem Header="ziele">
    <toolkit:LongListSelector x:Name="alarmList" Background="Transparent" IsFlatList="True"
        ItemTemplate="{StaticResource stopItemTemplate}" SelectionChanged="AlarmListSelectionChanged" />
</controls:PivotItem>

The SelectionChanged event:

    private void AlarmListSelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        var guid = ((AlarmItem)alarmList.SelectedItem).Id;
        NavigationService.Navigate(new Uri(string.Concat("/AlarmDetailPage.xaml?id=", guid), UriKind.Relative));
    }

To change details of an item I've subscribed the SelectionChanged event of the LongListSelector. That works as expected.

But if I tap on the checkbox - at first the clicked event of the checkbox is fired, but I don't recognize which checkbox was clicked (the property longlistselector.SelectedItem is old) and just after the SelectionChanged event has fired and try to navigate to the detail page like is happens if I intend to do that.

How can I separate these to events to avoid firing both? And how can I get the corresponding data item?

Thanks a lot...
Kind regards, Danny

Answer 1

You don't need listen to SelectionChanged event. In Click, Checked or Unchecked event handler you can get an item:

private void CheckBox_Checked(object sender, System.Windows.RoutedEventArgs e)
{
    var guid = ((sender as CheckBox).DataContext as AlarmItem).Id;
    NavigationService.Navigate(new Uri(string.Concat("/AlarmDetailPage.xaml?id=", guid), UriKind.Relative));
}