例如，当引发双击事件时，我有ListView，项目chang FontWeight。如何将状态保存到下一个程序启动？使用数据库？什么是更好的存储在数据库字符串变量，如Bold，ExtraBold，Normal。还是价值观？
存储状态的常用方法是什么
<Window.Resources>
<Style x:Key="itemstyle" TargetType="{x:Type ListViewItem}">
<EventSetter Event="MouseDoubleClick" Handler="HandleDoubleClick" />
</Style>
</Window.Resources>
<Grid Background="#FFF0F0F0">
<ListView ItemsSource="{Binding Items}" SelectedItem="{Binding SelectedEmployee}" Margin="0,0,0,62" ItemContainerStyle="{StaticResource itemstyle}">
<ListView.View>
<GridView>
<GridViewColumn Header="FirstName">
<GridViewColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding FirstName}" FontWeight="{Binding FontWeight}" />
</StackPanel>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
<GridViewColumn Header="SecondName">
<GridViewColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding FirstName}" FontWeight="{Binding FontWeight}" />
</StackPanel>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
<CheckBox Content="HideAllNormal" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked" HorizontalAlignment="Left" Margin="69,290,0,0" VerticalAlignment="Top"/>
</Grid>
代码：
namespace WpfApplication27
{
public partial class MainWindow : Window
{
ListViewModel LVM = new ListViewModel();
public MainWindow()
{
InitializeComponent();
DataContext = LVM;
}
protected void HandleDoubleClick(object sender, MouseButtonEventArgs e)
{
LVM.SelectedEmployee.FontWeight = FontWeights.Normal;
}
private void CheckBox_Checked(object sender, RoutedEventArgs e)
{
LVM.HideAllBold();
}
private void CheckBox_Unchecked(object sender, RoutedEventArgs e)
{
LVM.ShowAll();
}
}
public class ListViewModel : INotifyPropertyChanged
{
private ObservableCollection<Employee> items;
public ObservableCollection<Employee> Items
{
get
{
return items;
}
set
{
items = value;
RaisePropertyChaged("Items");
}
}
private ObservableCollection<Employee> WithBoldItems;
public Employee SelectedEmployee { get; set; }
public ListViewModel()
{
Items = new ObservableCollection<Employee>();
for (int i = 0; i < 10; i++)
{
Employee emp = new Employee();
emp.Number = i;
emp.FirstName = "Test";
emp.FontWeight = (FontWeight)new FontWeightConverter().ConvertFromString("Bold");
Items.Add(emp);
}
}
public void HideAllBold()
{
WithBoldItems = Items;
Items = new ObservableCollection<Employee>(Items.Where(key => key.FontWeight != FontWeights.Bold));
}
public void ShowAll()
{
Items = WithBoldItems;
}
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChaged(string info)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(info));
}
}
}
public class Employee : INotifyPropertyChanged
{
public int Number { get; set; }
public string FirstName { get; set; }
private FontWeight fontWeight = FontWeights.Normal;
public FontWeight FontWeight
{
get
{
return fontWeight;
}
set
{
fontWeight = value;
RaisePropertyChaged("FontWeight");
}
}
private void RaisePropertyChaged(string info)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(info));
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
}
答案 0 :(得分：0)
我已将状态保存在主应用程序检查中，希望它有所帮助。
/// <summary>
/// Initializes the singleton application object. This is the first line of authored code
/// executed, and as such is the logical equivalent of main() or WinMain().
/// </summary>
public App()
{
Microsoft.ApplicationInsights.WindowsAppInitializer.InitializeAsync(
Microsoft.ApplicationInsights.WindowsCollectors.Metadata |
Microsoft.ApplicationInsights.WindowsCollectors.Session);
this.InitializeComponent();
this.Suspending += OnSuspending;
}
/// <summary>
/// Invoked when the application is launched normally by the end user. Other entry points
/// will be used such as when the application is launched to open a specific file.
/// </summary>
/// <param name="e">Details about the launch request and process.</param>
protected async override void OnLaunched(LaunchActivatedEventArgs e)
{
#if DEBUG
Debug.WriteLine($"Installed location: {Windows.ApplicationModel.Package.Current.InstalledLocation.Path}");
if (System.Diagnostics.Debugger.IsAttached)
{
this.DebugSettings.EnableFrameRateCounter = false;
}
#endif
RootFrame = Window.Current.Content as Frame;
// Do not repeat app initialization when the Window already has content,
// just ensure that the window is active
if (RootFrame == null)
{
// Create a Frame to act as the navigation context and navigate to the first page
RootFrame = new Frame();
RootFrame.NavigationFailed += OnNavigationFailed;
Debug.WriteLine(e.PreviousExecutionState);
if (e.PreviousExecutionState == ApplicationExecutionState.Terminated || e.PreviousExecutionState == ApplicationExecutionState.ClosedByUser)
{
await xxxxx.Common.SuspensionManager.RestoreAsync();
}
if (true)
{
try
{
await xxxx(await Utils.DeserializeXML<xxx>(
await ApplicationData.Current.LocalFolder.GetFileAsync("xxx.xml")));
}
catch
{
Debug.WriteLine("No in xxx");
}
}
// Place the frame in the current Window
Window.Current.Content = RootFrame;
await AssetManager.InitAssets();
// Place the frame in the current Window
await AssetManager.FetchAssets();
}
if (RootFrame.Content == null)
{
// When the navigation stack isn't restored navigate to the first page,
// configuring the new page by passing required information as a navigation
// parameter
if (App.xxxx == null || App.xxxx.SessionId == null)
RootFrame.Navigate(typeof(xxxPage), e.Arguments);
else
RootFrame.Navigate(typeof(MainPage), e.Arguments);
}
// Ensure the current window is active
Window.Current.Activate();
}
void OnNavigationFailed(object sender, NavigationFailedEventArgs e)
{
throw new Exception("xxxxxx " + e.SourcePageType.FullName);
}
private async void OnSuspending(object sender, SuspendingEventArgs e)
{
// it would be best to have a SUSPEND state in the statechart for every possible
// state, but it's ok for now
Utils.ReleaseDisplay();
var deferral = e.SuspendingOperation.GetDeferral();
try {
if (App.LoggedUser != null)
{
await Utils.SerializeXML(await ApplicationData.Current.LocalFolder.CreateFileAsync(
"xxx.xml", CreationCollisionOption.ReplaceExisting), xxxxx);
await Utils.SerializeXML(await App.xxxFolder.CreateFileAsync(
"xxx.xml", CreationCollisionOption.ReplaceExisting), App.State);
}
}
catch (Exception e2)
{
Debug.WriteLine(e2);
}
await xxxxx.Common.SuspensionManager.SaveAsync();
deferral.Complete();
}
}