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C# visible doesn't works

I'm making a Universal application for Windows Phone 8.1 and have a problem with my code.
After TextBlock value become greater or equal than 22, some images should become visible. If the value is less than 22 all images should be invisible.
My question: How I can get visible images after textblock value >="22"
This is my code to hide images:
private void points_Loaded(object sender, RoutedEventArgs e)
{
int n = 0;
bool b = int.TryParse(points.Text, out n);
DataContext = this;
ImageVis = (b && n >= 22) ? Visibility.Visible : isibility.Collapsed;
}
private Visibility imageVis;
public Visibility ImageVis
{
get { return imageVis; }
set
{
imageVis = value;
RaisePropertyChanged("ImageVis");
}
}
public event PropertyChangedEventHandler PropertyChanged = delegate { };
protected void RaisePropertyChanged(string propertyName)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
This code part is from XAML:
<Image x:Name="hole17img"
HorizontalAlignment="Left"
Height="57"
Margin="10,3540,0,0"
VerticalAlignment="Top"
Width="380"
Source="Assets/septinpatsmit.png"
Stretch="Fill"
Visibility="{Binding ImageVis, Mode=TwoWay}"/>
I have problem with: RaisePropertyChanged("ImageVis");
The name 'RaisePropertyChanged' does not exist in the current context
Does this mean I have make some object with that name? or something else?
I can provide my My application so you can see what's happening.
My application sample

RaisePropertyChanged is MVVM Light's method and makes UI updated whenever you raise a property with the given name.In the XAML code behind , you bind ViewModel's properties to XAML properties and when RaisePropertyChanged triggers , it notifies the given property and UI is refreshed after.
You also need to use Converters to convert boolean to Visibility.In general , you need more MVVM Pattern knowledge to Windows projects.
Check out this post
http://www.mvvmlight.net/doc/

Selective coloring of the text in TextBox (Windows Store App)

Code in my MainPage.xaml
<TextBox x:Name="TextTextBox"
Text="{Binding Path=Text, Mode=TwoWay}"
TextWrapping="Wrap" />
.
.
.
<!--Button with some Command-->
<Button x:Name="SearchButton"
Content="Search"
HorizontalAlignment="Center"
Command="{Binding Command}"/>
Code in my ViewModel (property that is binded with TextBox)
public string Text
{
get
{
return ssModel.Text;
}
set
{
ssModel.Text = value;
OnPropertyChanged();
}
}
When you press SearchButton, is performing Command which return List of ints (this ints are indexes to coloring in TextBox).
For example I've Text:
LoremIpsumDolorSitAmet
Then I press SearchButton, Command return me for example list of three numbers {2, 5, 13}. Now I want to coloring TextTextBox characters on this positions so, I want to get something like:
And this is exactly what I want to get. Coloring text in TextTextBox on the specified possitions.
I change TextBox to RichEditBox and write DependencyProperty to bind control with property in View Model. This is class with DependencyProperty:
public class RichTextC : DependencyObject
{
public static string GetRichText(DependencyObject obj)
{
return (string)obj.GetValue(RichTextProperty);
}
public static void SetRichText(DependencyObject obj, string value)
{
obj.SetValue(RichTextProperty, value);
}
public static readonly DependencyProperty RichTextProperty =
DependencyProperty.Register("RichText", typeof(string), typeof(RichTextC), new PropertyMetadata(string.Empty, callback));
private static void callback(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var reb = (RichEditBox)d;
reb.Document.SetText(TextSetOptions.FormatRtf, (string)e.NewValue);
}
}
And RichEditBox at MainPage.xaml:
<RichEditBox local:RichTextC.RichText="{Binding MyRichText, Mode=TwoWay}"
Margin="0,30,0,0""/>
But I have a another problem, because this DependencyProperty bind only in one way. When I set text/content of property at View Model control RichEditBox at MainPage will be notify and show new text. But when I change content of RichEditBox at MainPage it does not notify property in View Model - so binding from View to View Model does not work.

The TextBox doesn't support multi-coloured text. If you want editable coloured text you'll need to use the RichEditBox instead.
However, there isn't a direct way to bind to the text of a RichEditBox. You can set the text and its character formatting programatically through the RichEditBox's ITextDocument interfaces. For example, the following will set position 2 to Red. You can loop through your list of ints to set all of its ranges before calling ApplyDisplayUpdates:
ITextDocument doc = rtb.Document;
ITextRange range = doc.GetRange(2,3);
range.CharacterFormat.ForegroundColor = Windows.UI.Colors.Red;
rtb.Document.ApplyDisplayUpdates();
The other possibility would be to create a string with RTF codes in it and set that with ITextDocument.SetText.
If you want to bind the Text you can create an attached property which accepts the RTF and calls SetText or which accepts your own simpler mark-up script and calls ITextRange.CharacterFormat.ForegroundColor. Either way it would be similar to what I demonstrated to bind HTML to a WebView in my blog entry Binding HTML to a WebView with Attached Properties

Can I access XAML elements in an array in the codebehind?

I've been looking around but I haven't been able to find anything on this. I am trying to get started making Windows 8.1 apps in C# with Visual Studio 2013 Pro. I want to be able to access multiple elements (particularly buttons or text blocks) in an array because this is more convenient for developing things like board games. For instance, if I were developing tic-tac-toe, I might use a series of buttons like this:
<Grid>
<Button Name="Cell00"/>
<Button Name="Cell01"/>
<Button Name="Cell02"/>
<Button Name="Cell10"/>
<Button Name="Cell11"/>
<Button Name="Cell12"/>
<Button Name="Cell20"/>
<Button Name="Cell21"/>
<Button Name="Cell22"/>
<Grid/>
Now for the function that would check for a win, I would have to check all possible combinations like this is in the code behind:
private bool CheckForWin()
{
if((Cell00 == Cell01) && (Cell01 == Cell02) && isNotBlank(Cell02)) return true;
if((Cell10 == Cell11) && (Cell11 == Cell12) && isNotBlank(Cell12)) return true
...
return false; //if none of the win conditions pass
}
This type of code would be extremely cumbersome. I would like to write it instead in a way that lets me check the array with for loops.
I realize that with tic-tac-toe, it is fairly easy to code it using brute force, but this was the first example that came to my head. Other games like Reversi or Go would not work well like this because of either the sheer size or the fact that pieces placed can change other cells than the one they were placed on.
Any help with this would be greatly appreciated.

This is not the correct way to use WPF. WPF is designed to use data binding....creating and manipulating UI elements directly is bad form. There are more posts/discussion/questions about this than you can imagine and I'll leave you to research them for yourself. In the mean time this is how you use WPF "properly":
First use NuGet to add MVVM lite to your project so that you get the ViewModelBase class and create a view model for a single cell:
public class Cell : ViewModelBase
{
private string _Text;
public string Text
{
get { return _Text; }
set { _Text = value; RaisePropertyChanged(() => this.Text); }
}
}
One level up you'll want a main model to encapsulate an array of these, this is where you will typically do all your game logic:
public class MainModel : ViewModelBase
{
private ObservableCollection<Cell> _Cells;
public ObservableCollection<Cell> Cells
{
get { return _Cells; }
set { _Cells = value; RaisePropertyChanged(() => this.Cells); }
}
public MainModel()
{
this.Cells = new ObservableCollection<Cell>(
Enumerable.Range(1, 100)
.Select(i => new Cell { Text = i.ToString() })
);
}
}
Notice that all I'm doing at the moment is creating a 100-element collection of cells. This main view model becomes the one that you assign to your window's data context:
public MainWindow()
{
InitializeComponent();
this.DataContext = new MainModel();
}
Now your XAML controls need to bind to this data. ItemsControl is used to render a collection of elements so use one of those and bind it to your array. You want them displayed in a 2D grid so replace the ItemsPanelTemplate with a WrapPanel. Finally add a DataTemplate for your Cell class so that a button gets drawn for each cell:
<Window.Resources>
<DataTemplate DataType="{x:Type local:Cell}">
<Button Width="32" Height="32" Content="{Binding Text}"/>
</DataTemplate>
</Window.Resources>
<ItemsControl ItemsSource="{Binding Cells}" Width="320" Height="320" HorizontalAlignment="Center" VerticalAlignment="Center">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
That's how you use WPF. Your logic is stored entirely in the view model and it's completely decoupled from the view. Here's what this particular code displays, it should be pretty self-evident how flexible this code is and easy to change:

That's very possible. Simply declare an array variable :
private Button[] _buttonArray;
populate the array once, maybe in constructor :
_buttonArray = new[] {Cell00, Cell01, .... , Cell22};
And all of the buttons are now accessible through _buttonArray.

GridView CheckBox binding

How to change the value of a text block inside a grid view in WPF based on the check box selection . Grid view in WPF is populated from a sql table which has ID and Value as columns.Value here is YES or NO.I am using linq to sql .
I have a check box associated to each ID in the grid view.when a user selects some rows ,i have to save the changes back to the database.
So based on the selection i have to change the value field in the row in this fashion:
If the text in the "Value" field of the grid view is "YES" then i have to change it to "NO"
If the text in the "Value" field of the grid view is "NO" then i have to change it to "YES"
I am able to populate data into the gridview ,but i am not sure whether my questions in the above scenario will fit in WPF and c#.Need some guidance.

The best way to do this is to bind both the Text block and the checkbox to the same backend field in the data model and then to use code converters.
Here is a simple example.
Say you have the following simple view model with one bool property:
class SimpleViewModel: INotifyPropertyChanged
{
private bool _checked;
// The property to bind to
public bool Checked
{
get { return _checked; }
set { _checked = value; OnPropertyChanged("Checked"); }
}
public event PropertyChangedEventHandler PropertyChanged;
public void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
Here is also a simple page with a text block and a text field that both bind to the same backend field.
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfApplication1"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<local:SimpleViewModel x:Key="simpleViewModel" />
<local:BoolToStringConverter x:Key="boolToStringConverter" />
</Window.Resources>
<Grid DataContext="{StaticResource simpleViewModel}">
<StackPanel>
<TextBlock Text="{Binding Checked, Converter={StaticResource boolToStringConverter}}" />
<CheckBox Content="something" IsChecked="{Binding Checked}" />
</StackPanel>
</Grid>
</Window>
Now notice that the text block binding statement contains a converter statement.
Text="{Binding Checked, Converter={StaticResource boolToStringConverter}}"
The converter here is very simple. It checks the value if it's true and returns Yes, otherwise returns NO.
public class BoolToStringConverter:IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
if (value == null) return null;
if ((bool)value == true)
return "YES";
else
return "NO";
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
// this scenario is not needed since the text block is read only
throw new NotImplementedException();
}
}

You need to do events. Click on the control and click the lightning bold and do it in the code behind in c#. The keyword is events. OnChanged, Onclicked, onrowchange, etc. is inside that properties box for that control and you change the value in the code.

Use two way binding to transfer changes from UI into database. Bind the checkboxes column to the Value field from SQL table. You will need a convertor for binding to transform from Yes/No into bool.
http://msdn.microsoft.com/en-us/magazine/cc163299.aspx#S3
http://msdn.microsoft.com/en-us/library/ms752347.aspx#data_conversion

WPF Binding Issue - UI Updates, Object Does Not

I'm having yet another WPF binding issue. Just when I think I've got this stuff figured out, I run into more problems... :S
Anyway... I've created a custom user control for selecting files. It's a simple textbox followed by a button contained within a grid. The property of the control with which I am working is called FilePath and the TextBox on this control is bound to that property. When the button is clicked, a SaveFileDialog is opened and the user selects a file. The UI correctly updates after the user selects the file.
The problem I seem to be having is that when I bind an object to the control (in this instance I have an object with a DocumentFilePath property) the object doesn't update when a new file is selected.
Here's the relevant code within my user control:
public static readonly DependencyProperty FilePathProperty = DependencyProperty.Register("FilePath", typeof(string), typeof(FileSave), new UIPropertyMetadata(string.Empty, OnFilePathChanged));
public string FilePath
{
get
{
return this.GetValue(FilePathProperty) as string;
}
set
{
this.SetValue(FilePathProperty, value);
this.OnPropertyChanged("FilePath");
}
}
private void OnPropertyChanged(string propName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
private static void OnFilePathChanged(object sender, DependencyPropertyChangedEventArgs e)
{
((FileSave)sender).OnPropertyChanged("FilePath");
}
And the user control is added into my Window programatically by using reflection on my object:
private void AddFileSave(PropertyInfo pi)
{
FileSave fs = new FileSave();
Binding b = new Binding(pi.Name);
fs.SetBinding(FileSave.FilePathProperty, b);
this.AddToGrid(fs); //adds the control into my window's grid in the correct row and column; nothing fancy here
}
It may be worth noting that if I load the window with an existing object, my user control displays properly but still won't register any changes within the object to which it is bound.
Please let me know if you guys need any more info.
Thanks in advance,
Sonny
EDIT: I've found a way around the problem, but this probably isn't a good solution. By watching the debugger carefully I found that when I set the FilePath property within my control, the object was being unbound. If anyone can shed some light on that, I would be most appreciative. In the mean time, I've changed the code that opens my SaveFileDialog to look like this:
private void Button_Click(object sender, RoutedEventArgs e)
{
Microsoft.Win32.OpenFileDialog ofd = new Microsoft.Win32.OpenFileDialog();
ofd.Multiselect = false;
ofd.Title = "Select document to import...";
ofd.ValidateNames = true;
ofd.ShowDialog();
if (this.GetBindingExpression(FilePathProperty) == null)
{
this.FilePath = ofd.FileName;
}
else //set value on bound object (THIS IS THE NEW PORTION I JUST ADDED)
{
BindingExpression be = this.GetBindingExpression(FilePathProperty);
string propName = be.ParentBinding.Path.Path;
object entity = be.DataItem;
System.Reflection.PropertyInfo pi = entity.GetType().GetProperty(propName);
pi.SetValue(entity, ofd.FileName, null);
}
if (!string.IsNullOrWhiteSpace(this.FilePath))
{
_fileContents = new MemoryStream();
using (StreamReader sr = new StreamReader(this.FilePath))
{
_fileContents = new MemoryStream(System.Text.ASCIIEncoding.ASCII.GetBytes(sr.ReadToEnd()));
}
}
else
{
_fileContents = null;
}
}

You're not specifying anywhere in your code that the FilePath property should be TwoWay so updates of the DP value won't get pushed to the bound source object's property. You can use either:
Binding b = new Binding(pi.Name){ Mode = BindingMode.TwoWay };
or you can set up your Dependency Property to use a default of TwoWay:
public static readonly DependencyProperty FilePathProperty = DependencyProperty.Register(
"FilePath", typeof(string), typeof(FileSave),
new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnFilePathChanged));
You should also follow Robert's suggestion of removing the manual PropertyChange event, and also don't EVER add any code other than GetValue and SetValue in your DP wrapper property. XAML calls GetValue and SetValue directly so will skip over anything else you add there - which can lead to very nasty bugs.

Why, yes! I most certainly can shed some light on that!
Also, if you're using .Net 4.0, today's your lucky day!
Consider the following fine method on your DependencyObject:
SetCurrentValue();
Yes! With this SINGULAR method, all your woes will drift away as a bad dream at the rooster's crow! (Well, ok, not really, but that is the method you're looking for.)
Short story very short: When you programmatically SetValue() on a control in your view layer, you blow away your bindings. SetCurrentValue() was added to the framework because you frequently want to drive a change in your bound object by setting that value directly. An alternate design would be to set the value in your bound object programmatically and let the updated value get pulled back into the view, but that's frequently clumsy.
(I strongly suspect that the absence of this method up to this point is largely responsible for the utter failure of the vast majority of NumericUpDown controls in WPF.)

First, you don't need to raise the PropertyChanged event when a dependency property changes; with dependency properties, change notification comes for free.
What's probably happening here: The default behavior for UpdateSourceTrigger is LostFocus, i.e. the source gets updated when the user presses TAB to move to the next field, or clicks on another control, or whatever. The text box isn't losing focus after your SaveFileDialog sets Text (since it probably doesn't even have the focus in the first place), so the source update never gets triggered.
To make it update the source whenever the Text property changes, set the UpdateSourceTrigger to PropertyChanged.
If that doesn't work, watch the Output window for binding errors.
Edit:
Here's a little prototype application I built. It works just fine: typing in the text box sets the property, clicking on the "Save" button sets the property, and the binding in the main window gets updated properly no matter what.
<Window x:Class="DependencyPropertyBindingDemo.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:demo="clr-namespace:DependencyPropertyBindingDemo"
Title="MainWindow" Height="350" Width="525">
<DockPanel>
<demo:FilePicker x:Name="Picker"
DockPanel.Dock="Top"
Margin="5" />
<TextBox DockPanel.Dock="Top"
Text="{Binding ElementName=Picker, Path=FilePath}" />
<TextBlock />
</DockPanel>
</Window>
<UserControl x:Class="DependencyPropertyBindingDemo.FilePicker"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<DockPanel>
<TextBox DockPanel.Dock="Left"
Width="200"
Text="{Binding FilePath, UpdateSourceTrigger=PropertyChanged}" />
<Button Width="50"
DockPanel.Dock="Left"
Command="{Binding Path=SaveCommand}">Save</Button>
<TextBlock />
</DockPanel>
</UserControl>
public partial class FilePicker : UserControl
{
public FilePicker()
{
SaveCommand = new FilePickerSaveCommand(this);
DataContext = this;
InitializeComponent();
}
public ICommand SaveCommand { get; set; }
public static readonly DependencyProperty FilePathProperty = DependencyProperty.Register("FilePath", typeof(string), typeof(FilePicker));
public string FilePath
{
get
{
return GetValue(FilePathProperty) as string;
}
set
{
SetValue(FilePathProperty, value);
}
}
}
public class FilePickerSaveCommand : ICommand
{
private FilePicker _FilePicker;
public FilePickerSaveCommand(FilePicker picker)
{
_FilePicker = picker;
}
public void Execute(object parameter)
{
_FilePicker.FilePath = "Testing";
}
public bool CanExecute(object parameter)
{
return true;
}
public event EventHandler CanExecuteChanged;
}