add doc

Signed-off-by: Nester.zhou <ester.zhou@huawei.com>

en/application-dev/reference/arkui-ts/ts-basic-components-marquee.md

+# Marquee
+
+
+> ![icon-note.gif](public_sys-resources/icon-note.gif) **NOTE**
+> This component is supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.
+
+
+The **\<Marquee>** component is used to display a scrolling piece of text.
+
+
+## Required Permissions
+
+None
+
+
+## Child Components
+
+None
+
+
+## APIs
+
+Marquee(value: { start: boolean, step?: number, loop?: number, fromStart?: boolean, src: string })
+
+- Parameters
+    | Name| Type| Mandatory| Default Value| Description| 
+  | -------- | -------- | -------- | -------- | -------- |
+  | start | boolean | Yes| - | Whether to start scrolling.| 
+  | step | number | No| 6 | Scrolling step.| 
+  | loop | number | No| -1 | Number of times the marquee will scroll. If the value is less than or equal to **0**, the marquee will scroll continuously.| 
+  | fromStart | boolean | No| true | Whether the text scrolls from the start.| 
+  | src | string | Yes| - | Text to scroll.| 
+
+
+## Events
+
+  | Name| Description| 
+| -------- | -------- |
+| onStart(callback:&nbsp;()&nbsp;=&gt;&nbsp;void) | Triggered when the marquee starts scrolling.| 
+| onBounce(callback:&nbsp;()&nbsp;=&gt;&nbsp;void) | Triggered when the marquee has reached the end.| 
+| onFinish(callback:&nbsp;()&nbsp;=&gt;&nbsp;void) | Triggered when the marquee has finished scrolling.| 
+
+
+## Example
+
+
+```
+@Entry
+@Component
+struct MarqueeExample {
+  @State start: boolean = false
+  @State fromStart: boolean = true
+  @State step: number = 50
+  @State loop: number = 3
+  @State src: string = "Running Marquee starts rolling"
+
+  build() {
+    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {
+      Marquee({
+        start: this.start,
+        step: this.step,
+        loop: this.loop,
+        fromStart: this.fromStart,
+        src: this.src
+      })
+        .fontColor(Color.White)
+        .fontSize(50)
+        .allowScale(false)
+        .fontWeight(FontWeight.Bold)
+        .backgroundColor(Color.Black)
+        .margin({bottom:40})
+        .onStart(() => {
+          console.log('Marquee animation complete onStart')
+        })
+        .onBounce(() => {
+          console.log('Marquee animation complete onBounce')
+        })
+        .onFinish(() => {
+          console.log('Marquee animation complete onFinish')
+        })
+        Button('start')
+          .onClick(() => {
+            this.start = true
+             })
+          .width(200)
+          .height(60)
+          .margin({bottom:20})
+    }
+    .width('100%')
+    .height('100%')
+  }
+}
+```
+
+![en-us_image_0000001193499234](figures/en-us_image_0000001193499234.gif)