我正在创建一个Windows 8应用程序，其中有一个滚动条和一个按钮。当页面启动时，我希望按钮在触摸滚动条之前不可见。我用这行代码使按钮不可见。
ContinueButton.Visibility = Visibility.Collapsed;
然而，当我进入滑块更改我的代码的一部分并使可见的按钮可见时，它不起作用。即使在触摸滑块之前，该按钮也可见。我究竟做错了什么。以下是相关代码的一部分。
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Ward_Obs_Roaming.Common;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Media.Imaging;
using Windows.UI.Xaml.Navigation;
// The User Control item template is documented at http://go.microsoft.com/fwlink/?LinkId=234236
namespace Ward_Obs_Roaming.UI.ObsUserControls
{
public sealed partial class TemperatureObsControl : UserControl
{
public string ObsIndicatorImage
{
get
{
if (IndicatorImage.Source != null)
return (IndicatorImage.Source as BitmapImage).UriSource.ToString();
else
return string.Empty;
}
}
public string MEWSScore
{
get;
set;
}
private string _Note = string.Empty;
public string Note
{
get { return _Note; }
set { _Note = value; }
}
public string TemperatureColor
{
get { return (TemperatureGrid.Background as SolidColorBrush).Color.ToString(); }
set
{
byte A = Byte.Parse(value.Substring(1, 2));
byte R = Byte.Parse(value.Substring(3, 2));
byte G = Byte.Parse(value.Substring(5, 2));
byte B = Byte.Parse(value.Substring(7, 2));
TemperatureGrid.Background = new SolidColorBrush(Color.FromArgb(A, R, G, B));
}
}
public string TemperatureResult
{
//get { return DegreesComboBox.SelectedItem.ToString() + DecimalComboBox.SelectedItem.ToString(); }
//set//getting data as x.y...split and set combo box items
//{
// string[] splitTemperature = value.Split('.');
// DegreesComboBox.SelectedItem = splitTemperature[0];
// DecimalComboBox.SelectedItem = "." + splitTemperature[1];
//}
get
{
return TemperatureSlider.Value.ToString("##.#") + "°c";
}
set
{
value = value.Replace("°c", string.Empty);
TemperatureSlider.Value = Double.Parse(value.ToString());
}
}
public Button TemperatureContinueButton
{
get
{
return ContinueButton;
}
}
public TemperatureObsControl()
{
this.InitializeComponent();
TemperatureSlider.ValueChanged += TemperatureSlider_ValueChanged;
TemperatureSlider.Value = 37;
ContinueButton.Content = "No Change";
ContinueButton.Visibility = Visibility.Collapsed;
}
void TemperatureSlider_ValueChanged(object sender, RangeBaseValueChangedEventArgs e)
{
ContinueButton.Content = "Update";
ContinueButton.Visibility = Visibility.Visible;
TemperatureTextBlock.Text = TemperatureSlider.Value.ToString("##.#") + "°c";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.White);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.White);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.White);
//int bloodOxygenLevel = Int32.Parse(BloodOxygenSlider.Value.ToString());
double temperature = TemperatureSlider.Value;
switch (CommonVariables.ObsCategory)
{
case ObsCategories.NormalObs:
{
//if (CommonVariables.is_Abnormal && CommonVariables.abnormal.temperature != null)
//{
// if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(0).Split(';').ElementAt<string>(1)))
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["RedObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/exclamationMark.png"));
// MEWSScore = "3";
// }
// else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(1).Split(';').ElementAt<string>(1)))
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = null;
// MEWSScore = "2";
// }
// else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(2).Split(';').ElementAt<string>(1)))
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = null;
// MEWSScore = "1";
// TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
// MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
// MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
// }
// else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(3).Split(';').ElementAt<string>(1)))
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
// MEWSScore = "0";
// }
// else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(4).Split(';').ElementAt<string>(1)))
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
// MEWSScore = "0";
// }
// else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(5).Split(';').ElementAt<string>(1)))
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = null;
// MEWSScore = "1";
// TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
// MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
// MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
// }
// else
// {
// TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
// IndicatorImage.Source = null;
// MEWSScore = "2";
// }
//}
if (CommonVariables.is_Abnormal && CommonVariables.abnormal.temperature != null)
{
if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(0).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["RedObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/exclamationMark.png"));
MEWSScore = "3";
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(1).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(2).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(3).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
MEWSScore = "0";
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(4).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
}
else
{
if (temperature <= 34)//<=34
{
TemperatureGrid.Background = (Application.Current as App).Resources["RedObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/exclamationMark.png"));
MEWSScore = "3";
}
else if (temperature <= 35)//34-35
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
else if (temperature <= 36)//35-36
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else if (temperature <= 37)//36-37
{
TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
MEWSScore = "0";
}
else if (temperature <= 38)//37-38
{
TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
MEWSScore = "0";
}
else if (temperature <= 39)//38-39
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else//>39
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
}
}
break;
case ObsCategories.NeurologicalObs:
{
if (CommonVariables.is_Abnormal && CommonVariables.abnormal.temperature != null)
{
if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(0).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(1).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(2).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
MEWSScore = "0";
}
else if (temperature <= double.Parse(CommonVariables.abnormal.temperature.ElementAt<string>(3).Split(';').ElementAt<string>(1)))
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
}
else
{
if (temperature <= 35)
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
else if (temperature <= 35.9 || (temperature <= 38.5 && temperature >= 38.1))
{
TemperatureGrid.Background = (Application.Current as App).Resources["YellowObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "1";
TemperatureTextBlock.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreLabel.Foreground = new SolidColorBrush(Colors.Black);
MEWSScoreTextBlock.Foreground = new SolidColorBrush(Colors.Black);
}
else if (temperature <= 38)//36-38
{
TemperatureGrid.Background = (Application.Current as App).Resources["GreenObsBrush"] as SolidColorBrush;
IndicatorImage.Source = new BitmapImage(new Uri("ms-appx:///Images/tickMark.png"));
MEWSScore = "0";
}
else//>=38.6
{
TemperatureGrid.Background = (Application.Current as App).Resources["AmberObsBrush"] as SolidColorBrush;
IndicatorImage.Source = null;
MEWSScore = "2";
}
}
}
break;
}
MEWSScoreTextBlock.Text = MEWSScore;
}
//private void DegreesComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
//{
// ContinueButton.Content = "Update";
// DegreesTextBlock.Text = DegreesComboBox.SelectedItem.ToString();
// int selectedDegrees = Int32.Parse(DegreesComboBox.SelectedItem.ToString());
// if (selectedDegrees < 30) //<30
// BindedTemperatureSP.Background = new SolidColorBrush(Colors.LightGreen);
// else if (selectedDegrees < 70)//30 to 70
// BindedTemperatureSP.Background = new SolidColorBrush(Colors.Green);
// else //>70
// BindedTemperatureSP.Background = new SolidColorBrush(Colors.Red);
//}
//private void DecimalComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
//{
// ContinueButton.Content = "Update";
// DecimalTextBlock.Text = DecimalComboBox.SelectedItem.ToString();
//}
private void MinusButton_Click(object sender, RoutedEventArgs e)
{
TemperatureSlider.Value -= TemperatureSlider.StepFrequency;
}
private void PlusButton_Click(object sender, RoutedEventArgs e)
{
TemperatureSlider.Value += TemperatureSlider.StepFrequency;
}
}
}
答案 0 :(得分：0)
第一次初始加载滑块并将其值设置为零时，甚至会调用TemperatureSlider_ValueChanged事件。
每次引发事件时，都可以通过检查滑块的值来避免此行为：
void TemperatureSlider_ValueChanged(object sender, RangeBaseValueChangedEventArgs e)
{
if (TemperatureSlider.Value != 0)
{
ContinueButton.Visibility = Visibility.Visible;
}
}
答案 1 :(得分：0)
您的活动被触发，因为您在订阅ValueChanged后正在更改Slider值：
public TemperatureObsControl()
{
this.InitializeComponent();
TemperatureSlider.ValueChanged += TemperatureSlider_ValueChanged; // here you subscribe
TemperatureSlider.Value = 37; // here you change
ContinueButton.Content = "No Change";
ContinueButton.Visibility = Visibility.Collapsed;
}
如果你没有向你的Slider添加Value=...属性，请检查你的xaml - 它还会触发事件并让你的按钮可见 - 这可能是主要的问题，因为你设置你的按钮是不可见的结构的结束。
请注意，对于您的情况（更改可见性），您可以通过转换器将可见性绑定到Silder的值。