My memo app supports multilingualization in new version 1.7

http://windowsphone.com/s?appid=01fada6f-ff7e-451b-b0b0-3bf3a5c0f655

I'm really happy to announce my memo app's new release version 1.7 !
In new version, my memo app supports multilingualization that are English and Japanese.

And second feature is that you can choose character color (black or white). You can customize character color and background color as you want.

So, please check the function in bellow Yourtube video.



Please download my memo app in your Windows Phone ! 
Thanks.

Cannot bind two types of data source to one UI target

I was also struggling the problem when I made binding between data source and UI ListBox target.
Today, I'd like to introduce the problem that we cannot bind "non-INotifyPropertyChanged property" and "INotifyPropertyChanged property" to same ListBox target.

First, I had written property binding like this. I had used "non-INotifyPropertyChanged property".

• The xaml code is here.

 <ListBox Height="595" ItemsSource="{Binding}" HorizontalAlignment="Left" Margin="12,6,0,0" Name="listBox1" VerticalAlignment="Top" Width="438">  
   <ListBox.ItemTemplate>  
     <DataTemplate>  
       <StackPanel HorizontalAlignment="Stretch" Orientation="Horizontal">  
         <TextBlock x:Name="Name1" FontSize="35" Text="{Binding Text1}" Foreground="Black"/>  
         <TextBlock x:Name="Name2" FontSize="35" Text="{Binding Text2}" Foreground="Black"/>  
       </StackPanel>  
     </DataTemplate>  
   </ListBox.ItemTemplate>  
 </ListBox>  

• The code behind is here.

 public partial class MainPage : PhoneApplicationPage  
 {  
   // Constructor  
   public MainPage()  
   {  
     InitializeComponent();  
     GetList();  
   }  

   public void GetList()  
   {  
     List<ItemProperties> items = new List<ItemProperties>();  
     items.Add(new ItemProperties { Text1 = "test01", Text2 = "test02" });  
     items.Add(new ItemProperties { Text1 = "test11", Text2 = "test12" });  
     listBox1.ItemsSource = items;  
   }  
 }  

 public class ItemProperties  
 {  
   private string m_Text1;  
   public string Text1  
   {  
     get { return m_Text1; }  
     set { m_Text1 = value; }  
   }  

   private string m_Text2;  
   public string Text2  
   {  
     get { return m_Text2; }  
     set { m_Text2 = value; }  
   }  
 }  

Second, I wanted to bind Foreground color in ListBox. So, I added "INotifyPropertyChanged property" as Foreground colors.
The code is like this. But I found I couldn't bind "INotifyPropertyChanged property" to Foreground color in this code.

• The xaml code is here.

 <ListBox Height="595" ItemsSource="{Binding}" HorizontalAlignment="Left" Margin="12,6,0,0" Name="listBox1" VerticalAlignment="Top" Width="438">  
   <ListBox.ItemTemplate>  
     <DataTemplate>  
       <StackPanel HorizontalAlignment="Stretch" Orientation="Horizontal">  
         <TextBlock x:Name="Name1" FontSize="35" Text="{Binding Text1}" Foreground="{Binding Color1}"/>  
         <TextBlock x:Name="Name2" FontSize="35" Text="{Binding Text2}" Foreground="{Binding Color2}"/>  
       </StackPanel>  
     </DataTemplate>  
   </ListBox.ItemTemplate>  
 </ListBox>  

• The code behind is here.

 public partial class MainPage : PhoneApplicationPage  
 {  
   public ObservableCollection<ItemProperties2> ItemCollection { get; private set; }  
   // Constructor  
   public MainPage()  
   {  
     InitializeComponent();  
     GetList();  
     GetList2();  
   }  

   public void GetList()  
   {  
     List<ItemProperties> items = new List<ItemProperties>();  
     items.Add(new ItemProperties { Text1 = "test01", Text2 = "test02" });  
     items.Add(new ItemProperties { Text1 = "test11", Text2 = "test12" });  
     listBox1.ItemsSource = items;  
   }  

   public void GetList2()  
   {  
     ItemCollection = new ObservableCollection<ItemProperties2>();  
     ItemCollection.Add(new ItemProperties2  
     {  
       Color1 = new SolidColorBrush(Colors.LightGray),  
       Color2 = new SolidColorBrush(Colors.Brown)  
     });  
     ItemCollection.Add(new ItemProperties2  
     {  
       Color1 = new SolidColorBrush(Colors.Cyan),  
       Color2 = new SolidColorBrush(Colors.Red)  
     });  
     DataContext = ItemCollection;  
   }  
 }  

 public class ItemProperties  
 {  
   private string m_Text1;  
   public string Text1  
   {  
     get { return m_Text1; }  
     set { m_Text1 = value; }  
   }  

   private string m_Text2;  
   public string Text2  
   {  
     get { return m_Text2; }  
     set { m_Text2 = value; }  
   }  
 }  

 public class ItemProperties2 : INotifyPropertyChanged  
 {  
   public event PropertyChangedEventHandler PropertyChanged;  
   public ItemProperties2() { }  

   private Brush m_Color1;  
   public Brush Color1  
   {  
     get { return m_Color1; }  
     set  
     {  
       m_Color1 = value;  
       OnPropertyChanged("Color1");  
     }  
   }  

   private Brush m_Color2;  
   public Brush Color2  
   {  
     get { return m_Color2; }  
     set  
     {  
       m_Color2 = value;  
       OnPropertyChanged("Color2");  
     }  
   }  

   protected void OnPropertyChanged(string name)  
   {  
     PropertyChangedEventHandler handler = this.PropertyChanged;  
     if (handler != null)  
       handler(this, new PropertyChangedEventArgs(name));  
   }  
 } 

It seems that "non-INotifyPropertyChanged property" is given priority over "INotifyPropertyChanged property".

I think the problem is a little foolish in now. But If your code is quite large amount, you may not be able to find the problem immediately.
I write previous blog post as the answer for the problem. Please check it also.

Suddenly my application crashes without errors when using property binding

I introduced property binding in a previous blog post. Today, I introduce a problem when I write code of property binding.


Property binding is easy to mistake property names. If you mistake property name, you can't bind property correctly but also an application suddenly crashes without any errors.


So, please look at this code attentively. If you write such code, you can pass build action, but your application crashes suddenly without errors.

 public class ItemProperties : INotifyPropertyChanged  
 {  
   public event PropertyChangedEventHandler PropertyChanged;  
   public ItemProperties() { }  

   private string m_Text1;  
   public string Text1  
   {  
     get { return Text1; }  
     set  
     {  
       m_Text1 = value;  
       OnPropertyChanged("Text1");  
     }  
   }  

   protected void OnPropertyChanged(string name)  
   {  
     PropertyChangedEventHandler handler = this.PropertyChanged;  
     if (handler != null)  
       handler(this, new PropertyChangedEventArgs(name));  
   }  
 } 

The wrong code is here. If you write like this, your application suddenly shutdown.

get { return Text1; }  

You need to write like this.

get { return m_Text1; }  

I don't know why debugger can't catch error, but I noticed we need to pay attention when we use property binding.

Property Binding using INotifyPropertyChanged and ObservableCollection

I was struggling against property binding using INotifyPropertyChanged and ObservableCollection.
Today, I introduce how to bind from properties in a class to UI properties by using INotifyPropertyChanged and ObservableCollection. And I'll show you the problem I encountered in next blog post.

• Sample code of property binding

I introduce a sample code binding from properties in ItemProperties class to TextBlock's properties in ListBox (One Way).

• The xaml code is here.

 <ListBox Height="595" ItemsSource="{Binding}" HorizontalAlignment="Left" Margin="12,6,0,0" Name="listBox1" VerticalAlignment="Top" Width="438">  
   <ListBox.ItemTemplate>  
     <DataTemplate>  
       <StackPanel HorizontalAlignment="Stretch" Orientation="Horizontal">  
         <TextBlock x:Name="Name1" FontSize="35" Text="{Binding Text1}" Foreground="{Binding Color1}"/>  
         <TextBlock x:Name="Name2" FontSize="35" Text="{Binding Text2}" Foreground="{Binding Color2}"/>  
       </StackPanel>  
     </DataTemplate>  
   </ListBox.ItemTemplate>  
 </ListBox>  

- Point - 

You need to add ItemsSource="{Binding}" in ListBx to bind properties from code behind. You also should not add like ItemsSource="{Binding Collection}", just write "{Binding}".

When you use DataTemplate in ListBox, you can't write like this in code behind.

Name1.Foreground = new SolidColorBrush(Colors.LightGray);

So you need to bind from properties as a class to UI  properties. Almost all of UI element properties (ex. Foreground, Text, any more) are implemented as dependency property. You can bind from properties as a class to UI  properties using dependency property. You can't bind using usual property.

• The code behind is here.

 public partial class MainPage : PhoneApplicationPage  
 {  
   public ObservableCollection<ItemProperties> ItemCollection { get; private set; }  
   // Constructor  
   public MainPage()  
   {  
     InitializeComponent();  
     GetList();  
   }  

   public void GetList()  
   {  
     ItemCollection = new ObservableCollection<ItemProperties>();  
     ItemCollection.Add(new ItemProperties  
     {  
       Text1 = "test01",  
       Text2 = "test01",  
       Color1 = new SolidColorBrush(Colors.LightGray),  
       Color2 = new SolidColorBrush(Colors.Brown)  
     });  

     ItemCollection.Add(new ItemProperties  
     {  
       Text1 = "test02",  
       Text2 = "test02",  
       Color1 = new SolidColorBrush(Colors.Cyan),  
       Color2 = new SolidColorBrush(Colors.Red)  
     });  

     ItemCollection.Add(new ItemProperties  
     {  
       Text1 = "test03",  
       Text2 = "test03",  
       Color1 = new SolidColorBrush(Colors.Orange),  
       Color2 = new SolidColorBrush(Colors.Purple)  
     });  

     DataContext = ItemCollection;  
   }  
 }  

 public class ItemProperties : INotifyPropertyChanged  
 {  
   public event PropertyChangedEventHandler PropertyChanged;  
   public ItemProperties() { }  

   private string m_Text1;  
   public string Text1  
   {  
     get { return m_Text1; }  
     set  
     {  
       m_Text1 = value;  
       OnPropertyChanged("Text1");  
     }  
   }  

   private string m_Text2;  
   public string Text2  
   {  
     get { return m_Text2; }  
     set  
     {  
       m_Text2 = value;  
       OnPropertyChanged("Text2");  
     }  
   }  

   private Brush m_Color1;  
   public Brush Color1  
   {  
     get { return m_Color1; }  
     set  
     {  
       m_Color1 = value;  
       OnPropertyChanged("Color1");  
     }  
   }  

   private Brush m_Color2;  
   public Brush Color2  
   {  
     get { return m_Color2; }  
     set  
     {  
       m_Color2 = value;  
       OnPropertyChanged("Color2");  
     }  
   }  

   protected void OnPropertyChanged(string name)  
   {  
     PropertyChangedEventHandler handler = this.PropertyChanged;  
     if (handler != null)  
       handler(this, new PropertyChangedEventArgs(name));  
   }  
 } 

• Result