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TimePicker

  • Artikkeli

The .NET Multi-platform App UI (.NET MAUI) TimePicker invokes the platform's time-picker control and allows you to select a time.

TimePicker defines the following properties:

  • Time of type TimeSpan, the selected time, which defaults to a TimeSpan of 0. The TimeSpan type indicates a duration of time since midnight.
  • Format of type string, a standard or custom .NET formatting string, which defaults to "t", the short time pattern.
  • TextColor of type Color, the color used to display the selected time.
  • FontAttributes of type FontAttributes, which defaults to FontAtributes.None.
  • FontFamily of type string, which defaults to null.
  • FontSize of type double, which defaults to -1.0.
  • CharacterSpacing, of type double, is the spacing between characters of the TimePicker text.

All of these properties are backed by BindableProperty objects, which means that they can be styled, and the properties can be targets of data bindings. The Time property has a default binding mode of BindingMode.TwoWay, which means that it can be a target of a data binding in an application that uses the Model-View-ViewModel (MVVM) pattern.

Note

The TimePicker doesn't include an event to indicate a new selected Time value. If you need to be notified of this, you can add an event handler for the PropertyChanged event.

In addition, TimePicker defines a TimeSelected event, which is raised when the selected time changes. The TimeChangedEventArgs object that accompanies the TimeSelected event has NewTime and OldTime properties, which specify the new and old time, respectively.

Create a TimePicker

When the Time property is specified in XAML, the value is converted to a TimeSpan and validated to ensure that the number of milliseconds is greater than or equal to 0, and that the number of hours is less than 24. The time components should be separated by colons:

<TimePicker Time="4:15:26" />

If the BindingContext property of TimePicker is set to an instance of a viewmodel containing a property of type TimeSpan named SelectedTime (for example), you can instantiate the TimePicker like this:

<TimePicker Time="{Binding SelectedTime}" />

In this example, the Time property is initialized to the SelectedTime property in the viewmodel. Because the Time property has a binding mode of TwoWay, any new time that the user selects is automatically propagated to the viewmodel.

In code, you can initialize the Time property to a value of type TimeSpan:

TimePicker timePicker = new TimePicker
{
  Time = new TimeSpan(4, 15, 26) // Time set to "04:15:26"
};

For information about setting font properties, see Fonts.

TimePicker and layout

It's possible to use an unconstrained horizontal layout option such as Center, Start, or End with TimePicker:

<TimePicker ···
            HorizontalOptions="Center" />

However, this is not recommended. Depending on the setting of the Format property, selected times might require different display widths. For example, the "T" format string causes the TimePicker view to display times in a long format, and "4:15:26 AM" requires a greater display width than the short time format ("t") of "4:15 AM". Depending on the platform, this difference might cause the TimePicker view to change width in layout, or for the display to be truncated.

Tip

It's best to use the default HorizontalOptions setting of Fill with TimePicker, and not to use a width of Auto when putting TimePicker in a Grid cell.

Platform differences

This section describes the platform-specific differences with the TimePicker control.

On Android, the Format property is respected and displayed by the control. However, when the picker control is shown by pressing on the control, only the hour, minute, and time of day can be changed.