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Xamarin.Forms ProgressBar

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The Xamarin.Forms ProgressBar control visually represents progress as a horizontal bar that is filled to a percentage represented by a float value. The ProgressBar class inherits from View.

The following screenshots show a ProgressBar on iOS and Android:

Screenshot of ProgressBar on iOS and Android

The ProgressBar control defines two properties:

  • Progress is a float value that represents the current progress as a value from 0 to 1. Progress values less than 0 will be clamped to 0, values greater than 1 will be clamped to 1.
  • ProgressColor is a Color that affects the interior bar color representing the current progress.

These properties are backed by BindableProperty objects, which means that the ProgressBar can be styled and be the target of data bindings.

The ProgressBar control also defines a ProgressTo method that animates the bar from its current value to a specified value. For more information, see Animate a ProgressBar.

Note

The ProgressBar does not accept user manipulation so it is skipped when using the Tab key to select controls.

Create a ProgressBar

A ProgressBar can be instantiated in XAML. Its Progress property determines the fill percentage of the inner, colored bar. The default Progress property value is 0. The following example shows how to instantiate a ProgressBar in XAML with the optional Progress property set:

<ProgressBar Progress="0.5" />

A ProgressBar can also be created in code:

ProgressBar progressBar = new ProgressBar { Progress = 0.5f };

Warning

Do not use unconstrained horizontal layout options such as Center, Start, or End with ProgressBar. On UWP, the ProgressBar collapses to a bar of zero width. Keep the default HorizontalOptions value of Fill and don't use a width of Auto when putting a ProgressBar in a Grid layout.

ProgressBar appearance properties

The ProgressColor property defines the inner bar color when the Progress property is greater than zero. The following example shows how to instantiate a ProgressBar in XAML with the ProgressColor property set:

<ProgressBar ProgressColor="Orange" />

The ProgressColor property can also be set when creating a ProgressBar in code:

ProgressBar progressBar = new ProgressBar { ProgressColor = Color.Orange };

The following screenshots show the ProgressBar with the ProgressColor property set to Color.Orange on iOS and Android:

Screenshot of styled ProgressBar on iOS and Android

Animate a ProgressBar

The ProgressTo method animates the ProgressBar from its current Progress value to a provided value over time. The method accepts a float progress value, a uint duration in milliseconds, an Easing enum value and returns a Task<bool>. The following code demonstrates how to animate a ProgressBar:

// animate to 75% progress over 500 milliseconds with linear easing
await progressBar.ProgressTo(0.75, 500, Easing.Linear);

For more information about the Easing enumeration, see Easing functions in Xamarin.Forms.