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C# WPF Binding to variable and property in code behind

I got an integer in my viewmodel and a string in my view that I need to show combined.
This is the code in the view:
Binding buttonBinding = new Binding() {
Path = new PropertyPath(nameof(ButtonViewModel.MyInteger)),
};
_button.SetBinding(Button.ContentProperty, buttonBinding);
Can I attach my string at some point or do I need to transfer it into the viewmodel and make the property a single string?

You could use the ContentStringFormat property to specify a StringFormat for the binding:
string s = "some string...";
Binding buttonBinding = new Binding()
{
Path = new PropertyPath(nameof(ButtonViewModel.MyInteger)),
};
_button.SetBinding(Button.ContentProperty, buttonBinding);
_button.ContentStringFormat = $"{{0}} {s}";

Change SearchView Text Color Xamarin.Android

I want to change the search text view color in Xamarin.Android. I have tried below code so far
searchView = this.Activity.FindViewById<Android.Support.V7.Widget.SearchView (Resource.Id.searchView);
searchView.SetOnQueryTextListener(this);
var textViewId = searchView.Context.Resources.GetIdentifier("android:id/search_src_text", null, null);
var textView = (searchView.FindViewById(textViewId) as TextView);
if (textView != null)
textView.SetTextColor(global::Android.Graphics.Color.White);
I am getting NULL when I try to capture the textView
In textViewId I'm getting the id of the view something like 126312727
Can anyone help me on above?

This is right out of app using Android.Support.V7.Widget.SearchView
var id = searchView.Context.Resources.GetIdentifier("search_src_text", "id", PackageName);
var searchEditText = searchView.FindViewById<EditText>(id);
searchEditText.SetTextColor(Color.Red);

I needed to use the below with AppCompat and CrossCurrentActivity plugin.
var searchEditText = (CrossCurrentActivity.Current?.Activity as MainActivity)?.FindViewById<AutoCompleteTextView>(Resource.Id.search_src_text);
searchEditText.SetTextColor(Color.Red);

Create Multiple Labels in Data Template

I have created a data template to use within a list view. This will later be expanded to add more content to each item in this list view. At the moment all the items that are bound to the observable collection are working as expected, except for one.
In each instance of the data template the bound properties are height, RouteName and routeStops. The height and RouteName are working fine but I'm not sure how to bind the routeStops correctly.
For each one of the RouteNames there are multiple stops, so for each data template use there must be one label that has the RouteName and multiple labels for each stop on the route (using routeStops).
I am not entirely sure how to achieve this, I can only seem to bind one stop to one label. I want to create them dynamically to allow for any amount of stops.
So the code behind that creates the data template (Just the constructor):
public MainRoutePageViewDetail(MessagDatabase database)
{
InitializeComponent();
BindingContext = mainroutepageviewmodel = new MainRoutePageViewModel(database,Navigation);
StackLayout mainstack = new StackLayout();
var routelisttemplate = new DataTemplate(() => {
ViewCell viewcell = new ViewCell();
stacklayout = new StackLayout();
stacklayout.SetBinding(StackLayout.HeightRequestProperty,"height");
viewcell.View = stacklayout;
// labels for template
var nameLabel = new Label { FontAttributes = FontAttributes.Bold, BackgroundColor = Color.LightGray };
nameLabel.HorizontalOptions = LayoutOptions.Center;
nameLabel.VerticalOptions = LayoutOptions.Center;
nameLabel.SetBinding(Label.TextProperty, "RouteName");
//inforLabel.SetBinding(Label.TextProperty, "Stops");
stacklayout.Children.Add(nameLabel);
StackLayout nextstack = new StackLayout();
var nameLabel2 = new Label { FontAttributes = FontAttributes.Bold, BackgroundColor = Color.Red };
nameLabel2.HorizontalOptions = LayoutOptions.Center;
nameLabel2.VerticalOptions = LayoutOptions.Center;
nameLabel2.SetBinding(Label.TextProperty, "routeStops");
nextstack.Children.Add(nameLabel2);
stacklayout.Children.Add(nextstack);
return viewcell;
});
ListView listviewofroutes = new ListView();
mainstack.Children.Add(listviewofroutes);
listviewofroutes.SetBinding(ListView.ItemsSourceProperty, "routeLabels");
listviewofroutes.ItemTemplate = routelisttemplate;
listviewofroutes.HasUnevenRows = true;
Content = mainstack;
}// end of constructor
This is bound to an ObservableCollection in the view model. Im going to leave this out as its irrelevant because the bindings work fine.
This calls down to functions in the model that collect data from SQL tables.
The function in the model that collects data:
public List<RouteInfo> getrouteInfo()
{
var DataBaseSelection = _connection.Query<RouteInfoTable>("Select * From [RouteInfoTable]");
List<RouteInfo> dataList = new List<RouteInfo>();
for (var i = 0; i < DataBaseSelection.Count; i++)
{
var DataBaseSelection2 = _connection.Query<RouteStopsTable>("Select StopOnRoute From [RouteStopsTable] WHERE RouteName = ? ",DataBaseSelection[i].RouteName);
dataList.Add(new RouteInfo
{
ID = DataBaseSelection[i].ID,
RouteName = DataBaseSelection[i].RouteName,
Stops = DataBaseSelection[i].Stops,
DayOf = DataBaseSelection[i].DayOf,
IsVisible = DataBaseSelection[i].IsVisible,
routeStops = DataBaseSelection2[i].StopOnRoute,
height = 200
});
}
return dataList;
}
The first table (RouteInfoTable) gets RouteName and some other information and the second table gets the stops on the route using the RouteName as a key. This is all added to a list of RouteInfo instances.
DataBaseSelection2 grabs all of the stops on the route but only one of them displays. I know why this is but I dont know how to display all three.
The Table definitions and class definitions as well as the selections from the tables are not an issue. I have debugged these and they are getting the correct information I just dont know how to display it on the front end in the way I want to. Here is a visual of what I mean if its getting complicated:
The best I can do is one route stop not all three.
An ideas how to achieve this?
Sorry if its complicated.

You can use Grouping in ListView to achieve this visual. Basically in this case you will be defining two DataTemplate(s) -
GroupHeaderTemplate for RouteName
ItemTemplate for StopsOnRoute.

Keep window on top WPF

I have problem to keep Window on TOP ? I work with MVVM WPF
I have this code in ConfigRole Model:
if (!System.Windows.Application.Current.Windows.OfType<ConfigRole>().Any())
{
ConfigRoleModel configRoleModel = new ConfigRoleModel();
ConfigRole winconfigRole = new ConfigRole();
winconfigRole.DataContext = configRoleModel;
winconfigRole.Show();
winconfigRole.Topmost = true;
winconfigRole.Focus();
}
Here the new Window is Correct, it is on TOP,
but after that, I want to show other Window on TOP from ConfigRoleModel ,
this is code ConfigRoleModel :
if (!System.Windows.Application.Current.Windows.OfType<ButtonListView>().Any())
{
ButtonListViewModel buttonListViewModel = new ButtonListViewModel();
ButtonListView winconfigRole = new ButtonListView();
winconfigRole.DataContext = buttonListViewModel;
winconfigRole.Show();
winconfigRole.Topmost = true;
winconfigRole.Focus();
}
So ,here I don't have this new Window on TOP!
I don't understand! it is the same code like the first ..
I try also with winconfigRole.ShowDialog();
and `Window.activate()
And the same Problem!
How can I fix it?
Thanks

Set the Owner property the ConfigRole to the MainWindow (or whatever window you open it from) and the Owner property of ButtonListView to the ConfigRole window:
if (!System.Windows.Application.Current.Windows.OfType<ButtonListView>().Any())
{
ButtonListViewModel buttonListViewModel = new ButtonListViewModel();
ButtonListView winconfigRole = new ButtonListView();
winconfigRole.DataContext = buttonListViewModel;
winconfigRole.Owner = System.Windows.Application.Current.Windows.OfType<ConfigRole>().FirstOrDefault(); //<--
winconfigRole.Show();
winconfigRole.Topmost = true;
winconfigRole.Focus();
}

Changing Xamarin Label in ListCell does not work

I have a problem with a ListView. I want each Cell to have a label and a switch but the text of the label does not appear.
Here is my code:
public class FilterPage : ContentPage
{
public FilterPage()
{
List<FilterCell> listContent = new List<FilterCell>();
foreach(string type in Database.RestaurantTypes)
{
FilterCell fc = new FilterCell();
fc.Text = type;
listContent.Add(fc);
}
ListView types = new ListView();
types.ItemTemplate = new DataTemplate(typeof(FilterCell));
types.ItemsSource = listContent;
var layout = new StackLayout();
layout.Children.Add(types);
Content = layout;
}
}
public class FilterCell : ViewCell
{
private Label label;
public Switch CellSwitch { get; private set; }
public String Text{ get { return label.Text; } set { label.Text = value; } }
public FilterCell()
{
label = new Label();
CellSwitch = new Switch();
var layout = new StackLayout
{
Padding = new Thickness(20, 0, 0, 0),
Orientation = StackOrientation.Horizontal,
HorizontalOptions = LayoutOptions.FillAndExpand,
Children = { label, CellSwitch }
};
View = layout;
}
}
If I enter a fixed Text in the FilterCell-Constructor it works fine (e.g.: label.Text = "Hello World")
When I create a Method for the ItemSelected-Event and read out the SelectedItem.Text Property I get the text I assigned as Value but it's never displayed. Only the switch is displayed when I try to run this Code.
Thanks for your help
Niko

Ohh boy. This code looks like a rape (sorry I had to say this).
Now let's see what's wrong:
The reason is you are mixing up data and view heavily.
The line
types.ItemTemplate = new DataTemplate(typeof(FilterCell));
means: "For each item in the list (ItemsSource) create a new filter cell". The FilterCells that you create in the loop are never displayed.
The easy fix
public class FilterPage : ContentPage
{
public FilterPage()
{
var restaurantTypes = new[] {"Pizza", "China", "German"}; // Database.RestaurantTypes
ListView types = new ListView();
types.ItemTemplate = new DataTemplate(() =>
{
var cell = new SwitchCell();
cell.SetBinding(SwitchCell.TextProperty, ".");
return cell;
});
types.ItemsSource = restaurantTypes;
Content = types;
}
}
There is a standard cell type that contains a label and a switch SwitchCell, use it.
As ItemsSource of your list, you have to use your data. In your case the list of restaurant types. I just mocked them with a static list.
The DataTemplate creates the SwitchCell and sets the Databinding for the Text property. This is the magic glue between View and data. The "." binds it to the data item itself. We use it, because our list contains items of strings and the Text should be exactly the string. (read about Databinding: https://developer.xamarin.com/guides/xamarin-forms/getting-started/introduction-to-xamarin-forms/#Data_Binding )
I striped away the StackLayout that contained the list. You can directly set the list as Content of the page.
Lesson
use standard controls, if possible
You should always try to remember to keep data and view apart from each other and use data binding to connect to each other.
Try to avoid unnecessary views.