当代码从 ListPicker 中获取选择时，我的（第一个）Windows Phone 应用程序不断崩溃，并且网络浏览器导航到该选择。它构建没有错误，但是当我运行它并按下按钮时崩溃了。我是编码方面的初学者，所以请降低你的答案:)
这是我的代码：
XAML：
<phone:PhoneApplicationPage
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
x:Class="SecurityCamera.Page1"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
mc:Ignorable="d"
shell:SystemTray.IsVisible="True">
<phone:PhoneApplicationPage.Resources>
<DataTemplate x:Name="ListPickerItemTemplate">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}" Margin="10 0 0 0"/>
</StackPanel>
</DataTemplate>
<DataTemplate x:Name="ListPickerFullModeItemTemplate">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}" Margin="10 0 0 0"/>
</StackPanel>
</DataTemplate>
</phone:PhoneApplicationPage.Resources>
<!--LayoutRoot is the root grid where all page content is placed-->
<Grid x:Name="LayoutRoot" Background="Transparent">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!--TitlePanel contains the name of the application and page title-->
<StackPanel Grid.Row="0" Margin="12,17,0,28">
<TextBlock Text="Security Camera Access" Style="{StaticResource PhoneTextNormalStyle}"/>
<TextBlock Text="Specify IP" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>
</StackPanel>
<!--ContentPanel - place additional content here-->
<Grid x:Name="ContentPanel" Margin="12,138,12,0" Grid.RowSpan="2" Opacity="0.99">
<TextBox x:Name="box1" HorizontalAlignment="Left" Height="70" Margin="31,172,0,0" TextWrapping="Wrap" Text="Http://" VerticalAlignment="Top" Width="400"/>
<TextBox x:Name="box2" HorizontalAlignment="Left" Height="70" Margin="31,242,0,0" TextWrapping="Wrap" Text="Http://" VerticalAlignment="Top" Width="400"/>
<TextBox x:Name="box3" HorizontalAlignment="Left" Height="70" Margin="31,312,0,0" TextWrapping="Wrap" Text="Http://" VerticalAlignment="Top" Width="400"/>
<TextBox x:Name="box4" HorizontalAlignment="Left" Height="70" Margin="31,382,0,0" TextWrapping="Wrap" Text="Http://" VerticalAlignment="Top" Width="400"/>
<Button Content="Connect" HorizontalAlignment="Left" Height="80" Margin="84,527,0,0" VerticalAlignment="Top" Width="305" Click="Button_Click_1"/>
<Button Content="Save" HorizontalAlignment="Left" Height="80" Margin="84,457,0,0" VerticalAlignment="Top" Width="305" Click="Button_Click_2"/>
<TextBlock HorizontalAlignment="Left" Margin="10,119,0,0" TextWrapping="Wrap" Text="Write IP's below to save - Include http:// before all addresses!" VerticalAlignment="Top"/>
</Grid>
<toolkit:ListPicker x:Name="defaultPicker" SelectionChanged="OnListPickerChanged" ExpansionMode="FullScreenOnly" Header="Saved IP's:" Margin="72,0,72,489" Grid.Row="1"/>
<phone:WebBrowser x:Name="webBrowser" HorizontalAlignment="Left" Margin="12,143,0,0" VerticalAlignment="Top" Width="456" Grid.RowSpan="2" Height="615" Opacity="100" Visibility="Visible"/>
</Grid>
</phone:PhoneApplicationPage>
XAML.CS:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using System.Xml;
using System.IO.IsolatedStorage;
using System.IO;
namespace SecurityCamera
{
public partial class Page1 : PhoneApplicationPage
{
public Page1()
{
InitializeComponent();
defaultPicker.ItemsSource = new List<string>() { { box1.Text }, { box2.Text }, { box3.Text }, { box4.Text } };
webBrowser.Visibility = System.Windows.Visibility.Collapsed;
// DEBUG MESSAGE - DELETE
MessageBox.Show("Visibility set to Collapsed (startup)");
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
------------------------THIS IS WHERE IT CRASHES --------------------------
//DEBUG MESSAGE - DELETE
MessageBox.Show("Button Pressed!");
string selectedItem;
selectedItem = (sender as ListPicker).SelectedItem.ToString();
// Do what you want with selectedItem
webBrowser.Navigate(new Uri(selectedItem));
//DEBUG MESSAGE - DELETE
MessageBox.Show("webBrowser.Navigate Executed...Making Visible");
webBrowser.Visibility = System.Windows.Visibility.Visible;
// DEBUG MESSAGE - DELETE
MessageBox.Show("webBrowser navigation sent - webBrowser Visibility set to Visible - Button Press");
}
private void OnListPickerChanged(object sender, SelectionChangedEventArgs e)
{
string selectedItem;
selectedItem = (sender as ListPicker).SelectedItem.ToString();
// Do what you want with selectedItem
// webBrowser.Navigate(new Uri(selectedItem));
}
private void Button_Click_2(object sender, RoutedEventArgs e)
{
defaultPicker.ItemsSource = new List<string>() { { box1.Text }, { box2.Text }, { box3.Text }, { box4.Text } };
// Write Text's into param
IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();
//create new file
using (StreamWriter writeFile = new StreamWriter(new IsolatedStorageFileStream("ip1.txt", FileMode.Create, FileAccess.Write, myIsolatedStorage)))
{
string someTextData = "{ box1.Text }";
writeFile.WriteLine(someTextData);
writeFile.Close();
}
}
}
}