Binding an integer variable in XAML to Screen Width and using it

Question

5.00/5 (1 vote)

See more:

Hi all,

I've got an animation that uses the ThicknessAnimation property to set the "To" and "From" aspects of the animation.

From="1000,0,-1000,0"

Now rather than hardcode the numbers I wish to bind a variable in XAML to the current or Actual screenwidth and then use this in place of the 1000 & -1000 values above.

How on earth can I do this in XAML?

I know how to declare an integer variable,

<system:int32 x:key="iScreenWidth" xmlns:x="#unknown" xmlns:system="#unknown">1024

but this doesn't represent the screenwidth as it resizes, nor do I know how to insert it into the From property to represent both 1000 & -1000.

Your help is really appreciated,

Jib

Posted 12-Aug-11 0:16am

Jibrohni

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Simon Bang Terkildsen · Answer 1 · 2011-08-12T00:48:00

I will start by discouraging you from using the screen resolution, because:
1) the resolution can be changed at anytime(as you state)
2) the application can be moved to another screen
3) the application can in worst case be placed such that it is partly shown on 4 different screens.

That said first you should create a Property which you can bind to

C#

public Thickness MyFrom
        {
            get { return (Thickness) GetValue(MyFromProperty); }
            set { SetValue(FromProperty, value);}
        }

        public static DependencyProperty MyFromProperty =
            DependencyProperty.Register("MyFromProperty", typeof (Thickness), typeof (MyClass));

You can then use SystemEvents.DisplaySettingsChanged In order to detect display changes (including resolution changes) and update your MyFrom property

Futhermore you would have to track the movement of your window so you know which screen(s) it's currently being displayed on.

Jibrohni · Answer 2 · 2011-08-17T22:07:00

Ok, someone gave some great direction on another forum, so credit here goes to Min Zhu, just wanted to share it as it's a popular question it seems:

I first created a value converter for Width to Thickness:

C#

[ValueConversion(typeof(double), typeof(Thickness))]
    public class ThicknessConverterFrom : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            double width = (double)value;
            Thickness t = new Thickness(width, 0, 0 - width, 0);

            return t;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            Thickness t = (Thickness)value;

            double width = new double();
            width = t.Left;

            return width;
        }
    }
    [ValueConversion(typeof(double), typeof(Thickness))]
    public class ThicknessConverterTo : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            double width = (double)value;
            Thickness t = new Thickness(0 - width, 0, width, 0);

            return t;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            Thickness t = (Thickness)value;

            double width = new double();
            width = t.Left;

            return width;
        }
    }

Then bound it as follows:

<ThicknessAnimation Duration="0:0:.5" Storyboard.TargetProperty="Margin" To="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Window}, Path=ActualWidth, Converter={StaticResource thicknessConvFrom}}" AccelerationRatio=".9"/>

Binding an integer variable in XAML to Screen Width and using it

2 solutions

Solution 1

Solution 2

Add your solution here

Preview 0