Question

我有一个滑块绑定到DoubleCollection Ticks（通过Ticks =“{Binding Ticks}”），它有一组值。 Ticks集合最终被清除并填充完全不同的值。问题是，在重新填充之后，即使集合中的值已经不同，滑块仍会按旧标记移动。

如何解决这个问题？

Answer 1

似乎tick集合不依赖于最小值和最大值。

滑块值取决于最小值和最大值，刻度仅为“装饰”。

以上示例应该有效。

基本上，在更改ticks集合时，我会更改Minimum和Maximum绑定值以适合tick集合的最小值和最大值。

C＃部分：

public partial class MainWindow : Window,INotifyPropertyChanged
{
    private double _value;
    private double _minimum;
    private double _maximum;
    private DoubleCollection _tickCollection;

    public MainWindow()
    {
        InitializeComponent();
        DataContext = this;

        TickCollection = new DoubleCollection();
        for (double i = 0.0; i < 5.0; i+=0.5)
        {
            TickCollection.Add(i);
        }
        Minimum = 0.0;
        Maximum = 5.0;
        Value = 2.3;

    }

    public double Value
    {
        get { return _value; }
        set
        {
            _value = value;
            OnPropertyChanged();
        }
    }

    public double Minimum
    {
        get { return _minimum; }
        set { _minimum = value; OnPropertyChanged(); }
    }

    public double Maximum
    {
        get { return _maximum; }
        set { _maximum = value; OnPropertyChanged(); }
    }

    public DoubleCollection TickCollection
    {
        get { return _tickCollection; }
        set
        {
            _tickCollection = value;
            OnPropertyChanged();
        }
    }

    private void ButtonBase_OnClick(object sender, RoutedEventArgs e)
    {
        TickCollection = new DoubleCollection();
        for (double i = 5.0; i < 10.0; i += 1.0)
        {
            TickCollection.Add(i);
        }
        Minimum = 5.0;
        Maximum = 10.0;
        Value = 2.3;

    }

    public event PropertyChangedEventHandler PropertyChanged;

    [NotifyPropertyChangedInvocator]
    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

XAML Conterpart：

    <Grid>
    <Slider x:Name="mySlider" Width="400" Height="40" Ticks="{Binding TickCollection}"
            TickPlacement="TopLeft"
            Minimum="{Binding Minimum}"
            Maximum="{Binding Maximum}"
            Value="{Binding Value,Mode=TwoWay}"
            ></Slider>

    <TextBlock Text="{Binding Value}" HorizontalAlignment="Center" Margin="0,20" VerticalAlignment="Top"></TextBlock>
    <Button Content="Change Ticks" Click="ButtonBase_OnClick" HorizontalAlignment="Center" Margin="0,60" VerticalAlignment="Top"></Button>
</Grid>

滑块不止一次完全改变刻度

1 个答案: