I am unable to access the controls such as textboxes residing in hubsections in OnLoadState method of the page.
I want to set the TEXT property of textboxes on loading the page. But without access, I can't.
Try Loaded instead:
<HubSection Header="Trailers">
<DataTemplate>
<TextBox Loaded="TextBox_Loaded" />
</DataTemplate>
</HubSection>
And then set the value like below :
private void TextBox_Loaded(object sender, RoutedEventArgs e)
{
var txtBox = (TextBox)sender;
txtBox.Text = "Some Text";
}
Copied from here.
Related
I have recently upgraded my OS to Windows 10 from Windows 8.1. I'm using VS 2013 With update 4.
My app using the Treeview control from XAMLToolkit, and it works perfectly on Windows 8.1 environment. But under Windows 10, it gives me the following error.
Please help.
This is the XAMLToolkit version I've used:
nuget.org/packages/winrtxamltoolkit.windows
Exception message:
System.Runtime.InteropServices.COMException: Error HRESULT E_FAIL has been returned from a call to a COM component.
at Windows.UI.Xaml.Controls.ItemsControl.get_ItemTemplate()
at WinRTXamlToolkit.Controls.HeaderedItemsControl.PrepareHeaderedItemsControlContainer(HeaderedItemsControl control, Object item, ItemsControl parentItemsControl, Style parentItemContainerStyle)
at WinRTXamlToolkit.Controls.HeaderedItemsControl.PrepareHeaderedItemsControlContainerForItemOverride(DependencyObject element, O
Stacktrace:
at Windows.UI.Xaml.Controls.ItemsControl.get_ItemTemplate()
at WinRTXamlToolkit.Controls.HeaderedItemsControl.PrepareHeaderedItemsControlContainer(HeaderedItemsControl control, Object item, ItemsControl parentItemsControl, Style parentItemContainerStyle)
at WinRTXamlToolkit.Controls.HeaderedItemsControl.PrepareHeaderedItemsControlContainerForItemOverride(DependencyObject element, Object item, ItemsControl parent, Style parentItemContainerStyle)
at WinRTXamlToolkit.Controls.TreeView.PrepareContainerForItemOverride(DependencyObject element, Object item)
at Windows.UI.Xaml.FrameworkElement.MeasureOverride(Size availableSize)
Inner exception is null
I encountered same issue, what i did is just removed the itemtemplate inside treeview control and added separately in page resource and i refered the itemtemplate to my treeview control. it solved my issue.
<Page.Resources>
<DataTemplate x:Name="TreeViewItemTemplate">
<Grid>
<TextBlock Text="{Binding Name}" />
</Grid>
<XCDATA:DataTemplateExtensions.Hierarchy>
<XCDATA:HierarchicalDataTemplate ItemsSource="{Binding Items}" />
</XCDATA:DataTemplateExtensions.Hierarchy>
</DataTemplate>
</Page.Resources>
<XC:TreeView
ItemTemplate="{StaticResource TreeViewItemTemplate}"
ItemsSource="{Binding ObjShopItems}">
</XC:TreeView>
Seems that you are using a HierarchicalDataTemplate in your XAML code for the TreeView. Replacing the XAML with the corresponding C# code will help. We can set the DataTemplateExtensions.Hierarchy attached property in code-behind in Loaded event for the TreeView, like this:
<controls:TreeView x:Name="treeView"
Loaded="treeView_Loaded"
...
And in code-behind:
private void treeView_Loaded(object sender, RoutedEventArgs e)
{
//don't know why, but in Windows 10 if this code is as XAML, the app falls with a ComExcpetion
//so the corresponding XAML should be commented out like this:
//...
//<controls:TreeView.ItemTemplate>
// <DataTemplate>
// <!-- <data:DataTemplateExtensions.Hierarchy>
// <data:HierarchicalDataTemplate ItemsSource="{Binding Folders}" />
// </data:DataTemplateExtensions.Hierarchy> -->
// <Grid>
//...
WinRTXamlToolkit.Controls.Data.DataTemplateExtensions.SetHierarchy(treeView.ItemTemplate, new WinRTXamlToolkit.Controls.Data.HierarchicalDataTemplate
{
ItemsSource = new Windows.UI.Xaml.Data.Binding { Path = new PropertyPath("Folders") }
});
}
I'm working on a Windows 8.1 app. I have added a basic page to my project, which automatically adds a back button:
<Button x:Name="backButton"
Margin="39,59,39,20"
Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}"
Style="{StaticResource NavigationBackButtonNormalStyle}"
VerticalAlignment="Top" />
The button works fine. However, when I move this button to an AppBar, it doesn't work. The view doesn't go back to the previous page.
What is going wrong in the latter case?
The AppBar isn't in the same namespace as the page and so the Command binding to the page's NavigationHelper property doesn't resolve. This is the case for any binding of the AppBar to the page.
You can fix this by setting the AppBar's DataContext to the page in page.Loaded
XAML
<Page.BottomAppBar>
<AppBar x:Name="bottomAppBar" IsOpen="True">
<Button x:Name="backButton"
Margin="39,59,39,20"
Command="{Binding NavigationHelper.GoBackCommand}"
Style="{StaticResource NavigationBackButtonNormalStyle}"
VerticalAlignment="Top" />
</AppBar>
</Page.BottomAppBar>
C#
public BasicPage1()
{
this.InitializeComponent();
this.navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += navigationHelper_LoadState;
this.navigationHelper.SaveState += navigationHelper_SaveState;
this.Loaded += BasicPage1_Loaded;
}
async void BasicPage1_Loaded(object sender, RoutedEventArgs e)
{
bottomAppBar.DataContext = this;
}
--Rob
I want to implement a Listbox binding directly and here is the code i used in WPF syntax
<ListBox Name="lboxData" ItemsSource="{Binding}">
<ListBox.ItemTemplate >
<DataTemplate>
<StackPanel>
<ToggleButton x:Name="toggleChild" Style="{StaticResource ChapterHeadingStyle}"
IsChecked="{Binding IsSelected, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ListBoxItem}}}" // This is what i have to change . I want to set it based on the status of the ListBoxItem & Given code is the one i used in WPF app
/>
<ListBox Visibility="{Binding IsChecked, ElementName=toggleChild, Converter={StaticResource boolToVis}}" ItemsSource="{Binding pages}" Margin="10,0,0,0" >
<ListBox.ItemTemplate >
<DataTemplate>
//here is displaying child items one by one ..
</DataTemplate>
</ListBox.ItemTemplate >
</ListBox>
</ListBox.ItemTemplate >
</DataTemplate>
</StackPanel>
</ListBox>
The problem is that in WP8 RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ListBoxItem} is not supported . So how can i achieve the same thing in WP8. I want to set the toggle button as Checked if the container ListboxItem is selected , else i want to set the IsChecked as False.
I'll start by writing a comparer class
public class ElementComparer : FrameworkElement
{
public object Element1
{
get { return (object)GetValue(Element1Property); }
set { SetValue(Element1Property, value); }
}
// Using a DependencyProperty as the backing store for Element1. This enables animation, styling, binding, etc...
public static readonly DependencyProperty Element1Property =
DependencyProperty.Register("Element1", typeof(object), typeof(ElementComparer), new PropertyMetadata(null, UpdateResult));
public object Element2
{
get { return (object)GetValue(Element2Property); }
set { SetValue(Element2Property, value); }
}
// Using a DependencyProperty as the backing store for Element2. This enables animation, styling, binding, etc...
public static readonly DependencyProperty Element2Property =
DependencyProperty.Register("Element2", typeof(object), typeof(ElementComparer), new PropertyMetadata(null, UpdateResult));
public bool Result
{
get { return (bool)GetValue(ResultProperty); }
set { SetValue(ResultProperty, value); }
}
// Using a DependencyProperty as the backing store for Result. This enables animation, styling, binding, etc...
public static readonly DependencyProperty ResultProperty =
DependencyProperty.Register("Result", typeof(bool), typeof(ElementComparer), new PropertyMetadata(false, OnResultChanged)); //added changed handler
private static void OnResultChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ElementComparer ec = d as ElementComparer;
//if true then set the element 2 to element 1 of the comparer otherwise null
ec.Element2 = ((bool)e.NewValue) ? ec.Element1 : null;
}
private static void UpdateResult(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ElementComparer ec = d as ElementComparer;
ec.Result = object.ReferenceEquals(ec.Element1, ec.Element2);
}
}
then I'll bind IsChecked from togglebutton to the Result of ElementComparer and will bind the Element1 and Element2 of the comaprer with the current item and the SelectedItem of lboxData (ListBox)
<ListBox Name="lboxData" ItemsSource="{Binding}">
<ListBox.ItemTemplate >
<DataTemplate>
<StackPanel>
<!--added Mode=TwoWay to binding of Element2-->
<local:ElementComparer x:Name="ElementComparer"
Element1="{Binding}"
Element2="{Binding SelectedItem, ElementName=bookTOCBox, Mode=TwoWay}" />
<!--removed Mode=OneWay from binding of IsChecked and added Mode=TwoWay-->
<ToggleButton x:Name="toggleChild" Content="{Binding name}"
Style="{StaticResource ChapterHeadingStyle}"
IsChecked="{Binding Result, ElementName=ElementComparer, Mode=TwoWay}"/>
...
</StackPanel>
the trick is to compare the selected item of the list to the current item to detect if it is selected as long as the name of parent listbox is "lboxData", this will work in WP8 too
Update summary
Removed one way binding from IsChecked property of toggle to Result of ElementComparer
Added two way binding to SelectedItem to Element2 of ElementComparer
added property changed handler for the Result property in ElementComparer
when the result is changes and is true (toggle is checked) push the value of Element1 to Element2
since the Element2 is bound to SelectedItem it force other items's result to false hence turn off the toggle and collapse the child list
added Mode=TwoWay to IsChecked property of toggle as seems quit unpredictable without it
Extras
additionally if you don't want to see ugly looking blue selection in list items then you may add the following to your resources too
<Style TargetType="ListBoxItem">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<Border Background="Transparent">
<ContentPresenter/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
I have created an application bar in code behind in a new Windows Phone HTML template. Originally the application bar was in xaml but I removed it. I created my application bar like I normally do in the code behind, although in this template for some reason it will not show up. I cannot figure out what the issue is, I have no errors. My code is below. The only thing I did in the XAML of the template is add a pivot control and I made the browser visibility false. My code is below. Any ideas?
XAML
<!--LayoutRoot is the root grid where all page content is placed-->
<Grid x:Name="LayoutRoot" Background="Transparent">
<phone:Pivot>
<phone:Pivot.TitleTemplate>
<DataTemplate>
<TextBlock Text="APPLICATION NAME">
</DataTemplate>
</phone:Pivot.TitleTemplate>
<phone:PivotItem Header="one">
</phone:PivotItem>
<phone:PivotItem Header="two">
</phone:PivotItem>
</phone:Pivot>
<phone:WebBrowser x:Name="Browser" Visibility="Collapsed"
IsScriptEnabled="True"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Loaded="Browser_Loaded"
Navigated="Browser_Navigated"
NavigationFailed="Browser_NavigationFailed"
ScriptNotify="Browser_ScriptNotify"/>
<ProgressBar x:Name="PerformanceProgressbar"
VerticalAlignment="Top"
IsIndeterminate="False"
Visibility="Collapsed">
</Grid>
XAML.CS
public MainPage()
{
InitializeComponent();
BuildLocalizedApplicationBar();
}
private void BuildLocalizedApplicationBar()
{
ApplicationBar appbar = new ApplicationBar();
/appbar.Mode = ApplicationBarMode.Minimized;
ApplicationBarMenuItem settings = new ApplicationBarMenuItem();
settings.Text = AppResources.MainPage_Settings;
settings.Click += settings_Click;
appbar.MenuItems.Add(settings);
}
You are just creating an object ApplicationBar, but you are not adding it to your Page. Page has a property ApplicationBar which you should set with your created instance of class ApplicationBar.
What would work:
private void BuildLocalizedApplicationBar()
{
ApplicationBar appbar = new ApplicationBar();
/appbar.Mode = ApplicationBarMode.Minimized;
ApplicationBarMenuItem settings = new ApplicationBarMenuItem();
settings.Text = AppResources.MainPage_Settings;
settings.Click += settings_Click;
appbar.MenuItems.Add(settings);
this.ApplicationBar = appbar; // or simply ApplicationBar = appbar;
// you can also add Appbar directly = ApplicationBar = new ApplicationBar();
// and then modify via this property
}
Note that you can have many ApplicationBars (objects) and exchange them easily.
Use this code would work:
click here for more details
private void BuildLocalizedApplicationBar()
{
ApplicationBar appbar = new ApplicationBar();
/appbar.Mode = ApplicationBarMode.Minimized;
ApplicationBarMenuItem settings = new ApplicationBarMenuItem();
settings.Text = AppResources.MainPage_Settings;
ApplicationBar.MenuItems.Add(settings );
settings.Click += new EventHandler(settings_Click);
}
I have created a html input check-boxes dynamically from code behind and after rendering the check-boxes on to aspx page I'm unable to get the checked property of those check-boxes on button click event. week is the enum with alldays of a week. Here the sample code.
HtmlInputCheckBox chkbx = new HtmlInputCheckBox();
chkbx.Attributes.Add("id", ((week)i).ToString());
chkbx.Attributes.Add("runat", "server");
chkbx.Attributes.Add("name", ((week)i).ToString());
chkbx.Attributes.Add("value", "checked");
HtmlGenericControl label = new HtmlGenericControl("label");
label.Attributes.Add("for", ((week)i).ToString());
if (i == 1 || i == 7)
{
label.Attributes.Add("class", "dow disabled");
label.Attributes.Add("disabled", "true");
}
else
{
label.Attributes.Add("class", "dow");
chkbx.Checked = true;
}
label.InnerText = ((week)i).ToString().Substring(0,2);
_dowcontrol.Controls.Add(chkbx);
_dowcontrol.Controls.Add(label);
ASPX page
<body>
<form id="form1" runat="server" method = "post">
<t2:mycontrol ID="SampleControl" runat="server" >
</t2:mycontrol>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
</form>
</body>
ASPX.CS page
What should be inside button click?
Tried
Request.Form["***"], FindControl("***")
In order for your dynamically created controls to interact with viewstate, events and other stages in the page life-cycle, they need to be created in the Init event. Creating these controls later in the life-cycle will exclude them from taking part in post value binding, viewstate binding, etc. Also note that you must recreate the controls on EVERY postback.
protected void Page_Init(object sender, EventArgs e)
{
// Do any dynamic control re/creation here.
}