Xamarin ActivityIndicator因绑定而冻结
我的活动指示器有问题。应用程序正在另一个线程中从REST服务器收集数据,并将其绑定到carousel视图。ActivityIndicator工作正常,但当我执行Xamarin ActivityIndicator因绑定而冻结,xamarin,xamarin.forms,activity-indicator,Xamarin,Xamarin.forms,Activity Indicator,我的活动指示器有问题。应用程序正在另一个线程中从REST服务器收集数据,并将其绑定到carousel视图。ActivityIndicator工作正常,但当我执行Device.beginInvokeMainThread(()=>BindingContext=ViewModel)时 ActivityIndicator冻结,直到绑定无法完成(通常为2-3秒)。 有什么办法可以避免这个问题吗? 代码: await Task.Run(async () => { DateTime startT
Device.beginInvokeMainThread(()=>BindingContext=ViewModel)时代码>
ActivityIndicator冻结,直到绑定无法完成(通常为2-3秒)。
有什么办法可以避免这个问题吗?
代码:
await Task.Run(async () =>
{
DateTime startTime = DateTime.Now;
try
{
selectedLocation = App.Session.DataProvider.GetLocation(selectedLocation.IdLocation, true);
List<OpLocationEquipment> locationEq = App.Session.DataProvider.GetLocationEquipment(new long[] { selectedLocation.IdLocation });
Logger.Logger.Log(Logger.EventID.Views.ItemDetailsPage.SelectedLocationInfo, Logger.Logger.Params(selectedLocation.IdLocation, selectedLocation.ToString()));
ViewModel = new LocationDetailsViewModel(selectedLocation, locationEq);
BindingContext = ViewModel;
}
catch (Exception ex)
{
await DisplayAlert(ResourceWrapper.GetValue(Constants.StringKey.ApplicationName), ResourceWrapper.GetValue(Constants.StringKey.UnexpectedErrorOccurredDuringConnectingToServer), ResourceWrapper.GetValue(Constants.StringKey.OK));
Logger.Logger.Log(EventID.Views.LoginPage.Exception, ex);
}
TimeSpan totalTime = DateTime.Now - startTime;
Logger.Logger.Log(EventID.Views.ItemDetailsPage.TotalTime, Logger.Logger.Params(totalTime.TotalSeconds));
});
HideActivityIndicator();
等待任务。运行(异步()=>
{
DateTime startTime=DateTime.Now;
尝试
{
selectedLocation=App.Session.DataProvider.GetLocation(selectedLocation.IdLocation,true);
List locationEq=App.Session.DataProvider.GetLocationEquipment(新的long[]{selectedLocation.IdLocation});
Logger.Logger.Log(Logger.EventID.Views.ItemDetailsPage.SelectedLocationInfo,Logger.Logger.Params(selectedLocation.IdLocation,selectedLocation.ToString());
ViewModel=新位置详情ViewModel(selectedLocation,locationEq);
BindingContext=ViewModel;
}
捕获(例外情况除外)
{
等待DisplayAlert(ResourceWrapper.GetValue(Constants.StringKey.ApplicationName)、ResourceWrapper.GetValue(Constants.StringKey.UnexpectedErrorCurredDuringConnectionToServer)、ResourceWrapper.GetValue(Constants.StringKey.OK));
Logger.Logger.Log(EventID.Views.LoginPage.Exception,ex);
}
TimeSpan totalTime=DateTime.Now-startTime;
Logger.Logger.Log(EventID.Views.ItemDetailsPage.TotalTime,Logger.Logger.Params(TotalTime.TotalSeconds));
});
HideActivityIndicator();
数据模板:
<DataTemplate x:Key="LocationTemplate">
<StackLayout>
<Grid VerticalOptions="FillAndExpand" Padding="0" Margin="0,0,0,-10">
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition Height="auto" />
</Grid.RowDefinitions>
<RelativeLayout Grid.Row="0" HorizontalOptions="FillAndExpand">
<ffimageloading:CachedImage Source="{Binding BackgroundImage}" Opacity="1" Aspect="Fill" RelativeLayout.WidthConstraint="{ConstraintExpression Type=RelativeToParent, Property=Width}" RelativeLayout.HeightConstraint="{ConstraintExpression Type=RelativeToParent, Property=Height}"/>
<ScrollView RelativeLayout.WidthConstraint="{ConstraintExpression Type=RelativeToParent, Property=Width}" RelativeLayout.HeightConstraint="{ConstraintExpression Type=RelativeToParent, Property=Height}">
<StackLayout>
<StackLayout Padding="15" BackgroundColor="White">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="auto"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="1" />
<RowDefinition Height="64"/>
</Grid.RowDefinitions>
<BoxView Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="3" BackgroundColor="{StaticResource CompanyColor}" HeightRequest="1" VerticalOptions="End" HorizontalOptions="FillAndExpand"/>
<StackLayout Grid.Column="0" Grid.Row="0" Grid.RowSpan="2">
<Label TextColor="{StaticResource CompanyColor}" FontSize="12" Text="{Binding LocationAddress}" VerticalOptions="CenterAndExpand" VerticalTextAlignment="Center" />
</StackLayout>
<Grid Grid.Row="1" Grid.Column="1">
<Grid.RowDefinitions>
<RowDefinition Height="auto"/>
<RowDefinition />
</Grid.RowDefinitions>
<Label Grid.Row="0" Text="Fuel status" TextColor="{StaticResource CompanyColor}" FontSize="7" HorizontalOptions="Center" HorizontalTextAlignment="Center"/>
<Label Text="{Binding FuelStatus}" Grid.Row="1" TextColor="{StaticResource CompanyColor}" FontSize="28" HorizontalOptions="Center" HorizontalTextAlignment="Center" />
</Grid>
<Grid Grid.Row="1" Grid.Column="2">
<Grid.RowDefinitions>
<RowDefinition Height="auto"/>
<RowDefinition />
</Grid.RowDefinitions>
<Label Grid.Row="0" Text="Device status" TextColor="{StaticResource CompanyColor}" FontSize="7" HorizontalOptions="Center" HorizontalTextAlignment="Center" />
<ffimageloading:CachedImage HorizontalOptions="Center" VerticalOptions="Start" DownsampleToViewSize="true"
Aspect="AspectFit" WidthRequest="32" HeightRequest="32" Grid.Row="1" Source="{Binding DeviceStatusImage}">
</ffimageloading:CachedImage>
</Grid>
</Grid>
</StackLayout>
<ListView
ItemsSource="{Binding Values}"
VerticalOptions="FillAndExpand"
HasUnevenRows="false"
BackgroundColor="Transparent"
CachingStrategy="RecycleElement"
HeightRequest="{Binding ListViewHeight}"
Margin="10,0,10,0"
SeparatorColor="White">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid Padding="15,0,15,15" Margin="0,0,0,0" HeightRequest="36">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="auto" />
<ColumnDefinition Width="5*"/>
</Grid.ColumnDefinitions>
<Label Text="{Binding Descr}" Style="{DynamicResource ListItemTextStyle}" Grid.Column="0" VerticalOptions="CenterAndExpand" FontSize="12"/>
<Label Text="{Binding Value}" Style="{DynamicResource ListItemTextStyle}" Grid.Column="1" VerticalOptions="CenterAndExpand" FontSize="12" HorizontalTextAlignment="End" />
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<StackLayout Padding="15" BackgroundColor="White">
<Label x:Name="lPlotTitle" TextColor="{StaticResource Primary}" VerticalOptions="CenterAndExpand" FontSize="11"/>
<Grid>
<oxy:PlotView x:Name="plotView" Model="{Binding PlotModel}" VerticalOptions = "Fill" HorizontalOptions = "Fill" WidthRequest="{Binding PlotWidth}" HeightRequest="350"/>
</Grid>
</StackLayout>
</StackLayout>
</ScrollView>
</RelativeLayout>
</Grid>
</StackLayout>
</DataTemplate>
设置绑定上下文本身不会更新任何UI元素,因此无需将其放入InvokeOnMainThread调用中
如果您消除了这一点,结巴应该会消失。设置绑定上下文本身不会更新任何UI元素,因此无需将其放入InvokeOnMainThread调用中
如果你摆脱了它,口吃就会消失。不要在
设备中这样做。beginInvokeMainThread(()=>)代码>将在UI线程上执行它,导致ActivityIndicator挂起。我认为我必须在主线程中进行数据绑定。我错了吗?请看我的答案:)不要在设备中执行此操作。BeginInvokeMainThread(()=>)代码>将在UI线程上执行它,导致ActivityIndicator挂起。我认为我必须在主线程中进行数据绑定。我错了吗?请看我的答案:)我已经尝试过了,但是我得到了TargetInvocationException:异常已被调用的目标抛出。-->Java.Lang.RuntimeException:无法在未调用Looper.prepare()的线程内创建处理程序。为什么要在任务中运行整个过程。run?GetLocation(selectedLocation.IdleLocation,true)和GetLocationEquipment(new long[]{selectedLocation.IdleLocation})正在从REST服务器收集数据,有时需要很多时间。这就是我在任务中运行它的原因。runI已尝试过此操作,但我得到TargetInvocationException:调用的目标已抛出异常。-->Java.Lang.RuntimeException:无法在未调用Looper.prepare()的线程内创建处理程序。为什么要在任务中运行整个过程。run?GetLocation(selectedLocation.IdleLocation,true)和GetLocationEquipment(new long[]{selectedLocation.IdleLocation})正在从REST服务器收集数据,有时需要很多时间。这就是我在任务中运行它的原因