How to make a button programatically visible in windows phone?

Question

I have a button named delete. I just want to make visible only when certain contions are met, so how could I do it??

The XAML code for button creation is

<Button x:Name="DeleteButton" Content="Delete" HorizontalAlignment="Left" Height="64" Margin="74,579,0,-9" VerticalAlignment="Top" Width="314" FontSize="24"/>

Answer 1

You have a Visibility property.

You have some ways to do it:

1. Just in code behind you should:

   if (condition)
   {
       DeleteButton.Visibility = Visibility.Visible; //Also possible to Collapse (hide).
   }
   

   The above code should help you make the button invisible and visible respectively.

   Note: This is less preferable, it's not dynamic and can cause to duplicates and unnecessary code.

2. The better way and more dynamic is:

   You can make a bool property and to bind the visibility button to it, like this:

   bool IsVisible { get; set; } //Code behind
   

   And in xaml:

   <!-- Pay attention: The Converter is still not written, follow next steps -->
   <Button x:Name="DeleteButton" 
           Content="Delete"
           HorizontalAlignment="Left" Height="64" Margin="74,579,0,-9" 
           VerticalAlignment="Top" Width="314" FontSize="24" 
           Visibility="{Binding IsVisible, 
                        Converter={StaticResource BooleanToVisibilityConverter}}" />
   

   The converter:

   public class BooleanToVisibilityConverter : IValueConverter
   {
       /// <summary>
       /// Converts a value.
       /// </summary>
       /// <param name="value">The value produced by the binding source.</param>
       /// <param name="targetType">The type of the binding target property.</param>
       /// <param name="parameter">The converter parameter to use.</param>
       /// <param name="culture">The culture to use in the converter.</param>
       /// <returns>A converted value. Returns Visible if the value is true; otherwise, collapsed.</returns>
       public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
       {
           return (bool)value ? Visibility.Visible : Visibility.Collapsed;
       }
   
       public object ConvertBack(object value, Type targetType, object parameter,CultureInfo culture)
       {
           throw new NotImplementedException();
       }
   }
   

   And at the resources in xaml you should add the converter so you can access it with the StaticResource:

   <Application
   x:Class="UI.App"
   xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   xmlns:converters="using:UI.Converters">
   
   <converters:BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter" />
   

   And then to change the IsVisible property for your need, if true it will be bound to Visible, if false, it will be collapsed.

   if (condition)
   {
       IsVisible = true;
   }
   

   For more information you should learn: binding, converters.