We Keep Coding

Not getting the selected Picker Id from model Xamarin Forms

I'm totally new to Xamarin Forms. I want to get the selected picker item Id when user is going to submit data. Data is populating to picker without any issue.
Model Class
public class CurrentStatus
{
public string id { get; set; }
public string current_status { get; set; }
}
public enum CurrentStatusId
{
NotApproved = 2,
Approved = 3,
Selected = 4,
NotSelected = 5
}
I bounded the ID like this in my view.
<local:HCImagePicker x:Name="currentstatus" Title="Current Status" SelectedIndexChanged="HandleStatusItemChanged" SelectedItem="{Binding CurrentStatusId}" ItemsSource="{Binding CurrentStatuses}" ItemDisplayBinding="{Binding current_status}" HorizontalOptions="FillAndExpand" Margin="0,0,0,10" Image="arrowdown" ImageAlignment="Right" ImageHeight="8" ImageWidth="12">
</local:HCImagePicker>
Just try to get the id after submiting data (In here simply I'm printing the value)
public async void SubmitData(object sender, EventArgs e){
var selectedId = currentstatus.SelectedItem;
await DisplayAlert("TEST", "Id is"+ selectedId, "OK");
}
Instead of getting a id (I don't want to get the selected value) , I'm getting a MyProject.Models.CurrentStatus.
Could someone help me to fix this.

Without actually knowing how your HCImagePicker looks like, I guess that SelectedItem is probably of type object.
Therefore you need to cast it and access it's properties correctly:
CurrentStatus selectedStatus = (currentStatus.SelectedItem as CurrentStatus);
if (selectedStatus == null)
return;
await DisplayAlert("TEST", "Id is"+ selectedStatus.id , "OK");
Personal note:
Do yourself a favour and don't use var. It might be comfortable and quick to use, however when it comes to casting around objects of any kind, you will definitely end up being confused, since you don't know what type of class you might end up with.
As far as I have experienced, using var instead of a proper type makes it harder to read and maintain your code in long term. Also you will be able to pinpoint possible error sources way faster when a cast goes wrong, because the compiler will warn you that what you attempt to do isn't possible.

C# WPF How can I have multiple DataContext

I am very new to WPF so despite finding other similar threads, my code is a little different so I don't know how to apply those solutions to mine.
<grid>
<CheckBox
x:Name="sortChk"
Content="Sort Variables"
IsChecked="{Binding SortVariables}"
/>
<b:FlatButton Command="{Binding ClickCommand}">
<TextBlock Text="Compare" FontSize="13"></TextBlock>
</b:FlatButton>
</grid>
Code behind looks something like this
string dataset1FullPath = null;
string dataset2FullPath = null;
string dataset1FilePath = null;
string dataset2FilePath = null;
public bool SortVariables { get; set; }
public SingleCompareWindow(string path1, string path2)
{
InitializeComponent();
dataset1FullPath = path1;
dataset2FullPath = path2;
dataset1FilePath = System.IO.Path.GetDirectoryName(path1);
dataset2FilePath = System.IO.Path.GetDirectoryName(path2);
//DataContext = this;
DataContext = new DataCompareVM(dataset1FullPath, dataset2FullPath, dataset1FilePath, dataset2FilePath, SortVariables);
}
You can see that I have commented out DataContext = this. If I dont comment it out and remove the other DataContext, then my SortVariables variable will take the value of the checkbox. If I have the other DataContext for the button click, then the checkbox will not bind. I need it to bind as I pass it as a parameter to DataCompareVM().
I'm very new to WPF and MVVM so forgive my ignorance.

You can't have more than one DataContext for a WPF control, you should move your properties to the ViewModel.

Yes, you can have different data contexts for different elements. But here you're trying to replace the same, window data context.
What you can do is use the named element. Replace your commented line with:
sortChk.DataContext = this;
Now, for the longest answer: you're not really doing MVVM here. As Fildor mentions, you should instead move the SortVariables property to the DataCompareVM ViewModel.
Since you seem to be struggling with MVVM, I believe reading my introductory book will help you get things straight: Learn WPF MVVM.

C# Windows 10 UWP Nested Listviews with Databinding

I have a app that retrieves comments from a website. I can programmatically add them to a StackPanel, calulating their indentation for comment replies but I'd like to learn how to bind a list of comments to a ListView and have it display correctly there.
My Comment Class looks like this:
class Comment
{
public List<Comment> Replies { get; set; }
public string Body { get; }
public int Level { get; set; }
public Comment(string BodyText)
{
Body = BodyText;
}
public Comment(string BodyText, List<Comment> replies, int level)
{
Body = BodyText;
Replies = replies;
Level = level;
}
}
So each Comment can have a List<> of comments (replies) to it and the Level variable indicates the depth of the comment.
What would be the process to set up a ListView so that I can bind a list of comments to it and those comments replies to those and so on? Or is there a better way to do this?
Thank you.
This is how I currently have it implemented which is visually correct but I'd like to use data binding rather than doing it through code.

Create a ListView, bind it's ItemsSource property to the list of top level comments. Use an ItemTemplate that contains the comment and another ListView in a vertical StackPanel. That inner ListView needs to get the same ItemTemplate it is in. I'm not sure if {StaticResource} will handle that, but it should.
If you use ObservableCollections this will actually be dynamic.

I recommend you to use the third party package WinRTXamlToolkit. Which contains a TreeView control that can meet your hierarchy requirements well. You can just bind the comments collection to the TreeView control code behind. Code example as follows:
Xaml Code
<controls:TreeView Width="400" MaxHeight="400" x:Name="Treeviewcomment">
<controls:TreeView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Body}"/>
<data:DataTemplateExtensions.Hierarchy>
<data:HierarchicalDataTemplate ItemsSource="{Binding Replies}" />
</data:DataTemplateExtensions.Hierarchy>
</DataTemplate>
</controls:TreeView.ItemTemplate>
</controls:TreeView>
Binding code
this.InitializeComponent();
ObservableCollection<Comment> comments = new ObservableCollection<Comment>
{
new Comment ("By the way,I have noticed that ..."),
new Comment("Has this been metioned anywhere before..",
new List<Comment>
{
new Comment("Delta upgrade..."),
new Comment("When only stuff that...",
new List<Comment> {
new Comment("That's blloby...")},
3)},
2),
new Comment("Just had to turn off..")
};
And the result:
Special nuget package for uwp: WinRT XAML Toolkit. And I also upload the above code example to GitHub.

How to control DynamicResource implementation in C#

In my program I would like to implement a DynamicResource from code-behind. Right now I am binding the Content of a Label to a string property in my Data Model...
<Label Content="{Binding DataModel.StringValue}" ... />
Following this question, I have implemented the string in my Data Model like so:
private string _stringValue = (string)Application.Current.Resources["nameOfResource"];
public string StringValue
{
get { return _cartsInSystem; }
set
{
_cartsInSystem = value;
NotifyPropertyChange(() => CartsInSystem);
}
}
I would like to make it so that every time the user changes the Resource Dictionary, this string value updates with the new value.
I am trying to achieve the same effect as something like this:
<Label Content="{DynamicResource nameOfResource}" ... />
Please let me know what I am doing wrong, and how I might correctly implement something like this.
UPDATE 1: As requested by #HighCore, this is an example of my code where I only have access to string values from code-Behind (or C# class)
(This is part of a ViewModel of a TreeView in my MainWindow)
//The "DisplayNames" for these nodes are created here and not accessible through xaml.
//This is because the xaml window has access to this code through it's itemsSource
private HierarchicalVM CreateCartsNode()
{
return new HierarchicalVM()
{
DisplayName = "Carts",
Children =
{
new CartConnection() { ConnectionDataModel = new CartConnectionModel(), DisplayName = "Cart Connection" },
new HierarchicalVM() {
DisplayName = "Cart Types",
Children = {
CreateCartType( new CartConfigModel() { DisplayName = "Default" }, new CartIO_Model() ),
},
Commands = { new Command(OpenAddCart) {DisplayName = "Add..."} }
}
}
};
}
This is the xaml of the above TreeView:
<!-- Tree view items & Functions -->
<TreeView ItemsSource="{Binding DataTree.Data}" ... />
Update 2: I have another perfect example of my problem...
I have a comboBox that has it's itemsSource bound to an ObservableCollection in my Data Model. Like so:
private ObservableCollection<string> _objCollection;
private string _notUsed = "Not Used";
private string _stop = "Stop";
private string _slow = "Slow";
public DataModel()
{
ObjCollection = new ObservableCollection<string>() { _notUsed, _stop, _slow };
}
public ObservableCollection<string> ObjCollection {...}
xaml:
<ComboBox ItemsSource="{Binding DataModel.ObjCollection}" ... />
If I want to make it so that the items in this comboBox change when the resource dictionary is changed, it looks like I'll need to handle it in C# rather than xaml.

After OP's UPDATE 2 and having a chat with him for a different question, I understood he was trying achieve localisation for his application. He would change Resource Dictionaries (for different languages) on the fly, and he wanted his C# code re-read/load values from Application.Current.Resources.
APPROACH ONE
After you changing the Resource Dictionary, You could use something like EventAggregator/Mediator to let other parts of the application (including ViewModels) know about Resource Dictionary change, and they respond to it by re-loading/reading resources/values from Application.Current.Resources
APPROACH TWO
OP doesn't want to introduce any new dependencies like EventAggregator/Mediator. So, I suggested this second approach. I know, it is not pretty, but here it goes..
You could have a global static event instead of EventAggregator/Mediaotr to let other parts of the application know that you swapped resource dictionary, and they will re-load/read values.
Read this answer about potential problems with static events and their subscriptions.

Simple Static Gridview

I've started to learn about GridView (XAML) for Windows 8 Store apps. I've used the ItemsPage example to try and have a look at the code.
My aim is use it as a horizontal menu, on the click event it will simply open another xaml page.
I've edited the SampleDataSource.cs file and filled up with the wanted content, i thought that there would be an easier, cleaner way of doing this. This Menu won't be dynamic and won't change so i'm looking for a way to statically add the menu items.
I can do the following to add a simple text entry;
<x:String>Item 1</x:String>
But i have i'm not sure how to bind to certain parts, such as the image and title elements
Right, i think i'm understanding this a little bit more. The following code would try and bind to itemsViewSource
<CollectionViewSource
x:Name="itemsViewSource"
Source="{Binding Items}"
d:Source="{Binding AllGroups, Source={d:DesignInstance Type=data:SampleDataSource, IsDesignTimeCreatable=True}}"/>
So would i need to create a new list, such as;
List<String> itemsList = new List<string>();
itemsList.Add("Item 1");
itemsList.Add("Item 2");
Only issue is that each item (line) would need a Title and Image text field and how to bind those to the correct items.

If your ItemsControl (GridView) needs to display more than one bound item for each list item - you need to bind its Source to a list of something more than a string unless you want to parse the strings. In your case you would have something like
List<TitleAndImageText> itemsList = new List<TitleAndImageText>();
itemsList.Add(new TitleAndImageText { Title = "Title 1", ImageText = "Image Text 1");
itemsList.Add(new TitleAndImageText { Title = "Title 2", ImageText = "Image Text 2");
Then in your ItemTemplate/DataTemplate you would have two TextBlocks - that bind to the properties of your item view model like this: Text="{Binding Title}", Text="{Binding ImageText}".
Of course you need to define your TitleAndImageText, e.g.
public class TitleAndImageText
{
public string Title { get; set; }
public string ImageText { get; set; }
}