# Component ID

**id** identifies a component uniquely within an application. This module provides APIs for obtaining the attributes of or sending events to the component with the specified ID.

>  **NOTE**
>
> The APIs of this module are supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.


## Attributes

| Name  | Type    | Description                        |
| -----| -------- | ----------------------------- |
| id   | string   | Unique ID you assigned to the component.<br>Default value: **''**|


## APIs


### getInspectorByKey<sup>9+</sup>

getInspectorByKey(id: string): string

Obtains all attributes of the component with the specified ID, excluding the information about child components.

**Parameters**

| Name  | Type     | Mandatory    | Description       |
| ---- | -------- | ---- | -------------|
| id   | string   | Yes   | ID of the component whose attributes are to be obtained.|

**Return value**

| Type       | Description            |
| -------| -------------- |
| string | JSON string of the component attribute list.|

### getInspectorTree<sup>9+</sup>

getInspectorTree(): string

Obtains the component tree and component attributes.

**Return value**

| Type    | Description                           |
| ------ | --------------------------- |
| string | JSON string of the component tree and component attribute list.|

### sendEventByKey<sup>9+</sup>

sendEventByKey(id: string, action: number, params: string): boolean

Sends an event to the component with the specified ID.

**Parameters**

| Name      | Type     | Mandatory      | Description                        |
| ------ | -------| ---- | -------------------------- |
| id     | string | Yes   | ID of the component to which the event is to be sent.                     |
| action | number | Yes   | Type of the event to be sent. The options are as follows:<br>- **10**: click event.<br>- **11**: long-click event.|
| params | string | Yes   | Event parameters. If there is no parameter, pass an empty string **""**.           |

**Return value**

| Type         | Description                        |
| -------- | --------------------------|
| boolean  | Returns **true** if the component with the specified ID is found; returns **false** otherwise.|

### sendTouchEvent<sup>9+</sup>

sendTouchEvent(event: TouchObject): boolean

Sends a touch event.

**Parameters**

| Name     | Type           | Mandatory | Description                                                        |
| ----- | ----------- | ---- | ------------------------------------------------------------ |
| event | TouchObject | Yes   | Location where a touch event is triggered. For details, see [TouchEvent](ts-universal-events-touch.md#touchevent).|

**Return value**

| Type     | Description                        |
| ------- | ---------------------------|
| boolean | Returns **true** if the event is sent successfully; returns **false** otherwise.|

### sendKeyEvent<sup>9+</sup>

sendKeyEvent(event: KeyEvent): boolean

Sends a key event.

**Parameters**

| Name   | Type    | Mandatory     | Description                                                        |
| ----- | -------- | ----  | ------------------------------------------------------------ |
| event | KeyEvent | Yes    | Key event. For details, see [KeyEvent](ts-universal-events-key.md#keyevent).|

**Return value**

| Type     | Description                          |
| ------- | ------------------------------|
| boolean | Returns **true** if the event is sent successfully; returns **false** otherwise.|

### sendMouseEvent<sup>9+</sup>

sendMouseEvent(event: MouseEvent): boolean

Sends a mouse event.

**Parameters**

| Name    | Type      | Mandatory      | Description                                    |
| ----- | ---------- | ----  | --------------------------------------- |
| event | MouseEvent | Yes   | Mouse event. For details, see [MouseEvent](ts-universal-mouse-key.md#mouseevent).|

**Return value**

| Type     | Description                                |
| ------- | ---------------------------------- |
| boolean | Returns **true** if the event is sent successfully; returns **false** otherwise.|

## Example

```ts
// xxx.ets
class Utils {
  static rect_left;
  static rect_top;
  static rect_right;
  static rect_bottom;
  static rect_value;

  static getComponentRect(key) {
    let strJson = getInspectorByKey(key);
    let obj = JSON.parse(strJson);
    console.info("[getInspectorByKey] current component obj is: " + JSON.stringify(obj));
    let rectInfo = JSON.parse('[' + obj.$rect + ']')
    console.info("[getInspectorByKey] rectInfo is: " + rectInfo);
    this.rect_left = JSON.parse('[' + rectInfo[0] + ']')[0]
    this.rect_top = JSON.parse('[' + rectInfo[0] + ']')[1]
    this.rect_right = JSON.parse('[' + rectInfo[1] + ']')[0]
    this.rect_bottom = JSON.parse('[' + rectInfo[1] + ']')[1]
    return this.rect_value = {
      "left": this.rect_left, "top": this.rect_top, "right": this.rect_right, "bottom": this.rect_bottom
    }
  }
}

@Entry
@Component
struct IdExample {
  @State text: string = ''

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {

      Button() {
        Text('onKeyTab').fontSize(25).fontWeight(FontWeight.Bold)
      }.margin({ top: 20 }).backgroundColor('#0D9FFB')
      .onKeyEvent(() => {
        this.text = "onKeyTab"
      })

      Button() {
        Text('click to start').fontSize(25).fontWeight(FontWeight.Bold)
      }.margin({ top: 20 })
      .onClick(() => {
        console.info(getInspectorByKey("click"))
        console.info(getInspectorTree())
        this.text = "Button 'click to start' is clicked"
        setTimeout(() => {
          sendEventByKey("longClick", 11, "")
        }, 2000)
      }).id('click')

      Button() {
        Text('longClick').fontSize(25).fontWeight(FontWeight.Bold)
      }.margin({ top: 20 }).backgroundColor('#0D9FFB')
      .gesture(
      LongPressGesture().onActionEnd(() => {
        console.info('long clicked')
        this.text = "Button 'longClick' is longclicked"
        setTimeout(() => {
          let rect = Utils.getComponentRect('onTouch')
          let touchPoint: TouchObject = {
            id: 1,
            x: rect.left + (rect.right - rect.left) / 2,
            y: rect.top + (rect.bottom - rect.top) / 2,
            type: TouchType.Down,
            screenX: rect.left + (rect.right - rect.left) / 2,
            screenY: rect.left + (rect.right - rect.left) / 2,
          }
          sendTouchEvent(touchPoint)
          touchPoint.type = TouchType.Up
          sendTouchEvent(touchPoint)
        }, 2000)
      })).id('longClick')

      Button() {
        Text('onTouch').fontSize(25).fontWeight(FontWeight.Bold)
      }.type(ButtonType.Capsule).margin({ top: 20 })
      .onClick(() => {
        console.info('onTouch is clicked')
        this.text = "Button 'onTouch' is clicked"
        setTimeout(() => {
          let rect = Utils.getComponentRect('onMouse')
          let mouseEvent: MouseEvent = {
            button: MouseButton.Left,
            action: MouseAction.Press,
            x: rect.left + (rect.right - rect.left) / 2,
            y: rect.top + (rect.bottom - rect.top) / 2,
            screenX: rect.left + (rect.right - rect.left) / 2,
            screenY: rect.top + (rect.bottom - rect.top) / 2,
            timestamp: 1,
            target: {
              area: {
                width: 1,
                height: 1,
                position: {
                  x: 1,
                  y: 1
                },
                globalPosition: {
                  x: 1,
                  y: 1
                }
              }
            },
            source: SourceType.Mouse
          }
          sendMouseEvent(mouseEvent)
        }, 2000)
      }).id('onTouch')

      Button() {
        Text('onMouse').fontSize(25).fontWeight(FontWeight.Bold)
      }.margin({ top: 20 }).backgroundColor('#0D9FFB')
      .onMouse(() => {
        console.info('onMouse')
        this.text = "Button 'onMouse' in onMouse"
        setTimeout(() => {
          let keyEvent: KeyEvent = {
            type: KeyType.Down,
            keyCode: 2049,
            keyText: 'tab',
            keySource: 4,
            deviceId: 0,
            metaKey: 0,
            timestamp: 0
          }
          sendKeyEvent(keyEvent)
        }, 2000)
      }).id('onMouse')

      Text(this.text).fontSize(25).padding(15)
    }
    .width('100%').height('100%')
  }
}
```