harmony 鸿蒙TextClock

2022-08-09
浏览 (669)

TextClock

The <TextClock> component displays the current system time in text format for different time zones. The time is accurate to seconds.

NOTE

This component is supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.

Child Components

Not supported

APIs

TextClock(options?: { timeZoneOffset?: number, controller?: TextClockController })

Parameters

Name	Type	Mandatory	Description
timeZoneOffset	number	No	Time zone offset. The value range is [-14, 12], indicating UTC+12 to UTC-12. A negative value indicates Eastern Standard Time, and a positive value indicates Western Standard Time. For example, -8 indicates UTC+8. For countries or regions crossing the International Date Line, use -13 (UTC+13) and -14 (UTC+14) to ensure consistent time within the entire country or region. If the set value is not within the valid range, the time zone offset of the current system will be used. Default value: time zone offset of the current system
controller	TextClockController	No	Controller to control the status of the component.

Attributes

In addition to the universal attributes, the following attributes are supported.

Name	Type	Description
format	string	Time format. y: year M: month d: day E: day of week (Prioritize the full name; use the abbreviation only when the space is insufficient.) H: hour (0-23) h: hour (1-12) m: minute s: second SS: centisecond SSS: millisecond a: morning/afternoon (This parameter does not take effect when the hour part is set to H.) Separators: slashes (/), hyphens (-), dots (.), or any custom characters (which cannot be letters) used to separate the parts of the date The parts of the date can be used alone or combined with each other as needed. When an invalid letter is set, the letter is ignored. Default value: hh:mm:ss

The following table shows how different settings of format work out.

Input Format	Display Effect
EEEE, M, d, yyyy	Saturday, February 4, 2023
MMM d, yyyy	February 4, 2023
EEEE, M, d	Saturday, February 4
MMM dd	February 4
MM/dd/yyyy	02/04/2023
EEEE MM dd	Saturday February 04
yyyy	2023
yy	23
MM	February
M	February
dd (complete date)	04
d	4
EEEE (full name)	Saturday
E, EE, EEE (abbreviation)	Sat
MMM d, yyyy	February 4, 2023
yyyy/M/d	2023/2/4
yyyy-M-d	2023-2-4
yyyy.M.d	2023.2.4
HH:mm:ss	17:00:04
aa hh:mm:ss	5:00:04 AM
hh:mm:ss	5:00:04
HH:mm	17:00
aa hh:mm	5:00 AM
hh:mm	5:00
mm:ss	00:04
mm:ss.SS	00:04.91
mm:ss.SSS	00:04.536
hh:mm:ss aa	5:00:04 AM
HH	17

Events

In addition to the universal events, the following events are supported.

Name	Description
onDateChange(event: (value: number) => void)	Called when the time changes in seconds. - value: Unix time stamp, which is the number of seconds that have elapsed since the Unix epoch.

TextClockController

Implements the controller of the <TextClock> component. You can bind the controller to the component to control its start and stop. A <TextClock> component can be bound to only one controller.

Objects to Import

controller: TextClockController = new TextClockController();

start

start()

Starts the component.

stop

stop()

Stops the component.

Example

@Entry
@Component
struct Second {
  @State accumulateTime: number = 0
  // Objects to import
  controller: TextClockController = new TextClockController()
  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
      Text('Current milliseconds is ' + this.accumulateTime)
        .fontSize(20)
      // Display the system time in 12-hour format for the UTC+8 time zone, accurate to seconds.
      TextClock({ timeZoneOffset: -8, controller: this.controller })
        .format('aa hh:mm:ss')
        .onDateChange((value: number) => {
          this.accumulateTime = value
        })
        .margin(20)
        .fontSize(30)
      Button("start TextClock")
        .margin({ bottom: 10 })
        .onClick(() => {
          // Start the text clock.
          this.controller.start()
        })
      Button("stop TextClock")
        .onClick(() => {
          // Stop the text clock.
          this.controller.stop()
        })
    }
    .width('100%')
    .height('100%')
  }
}

text_clock