1# Using TaskPool for Independent Time-Consuming Tasks 2 3For a time-consuming task that runs independently, you only need to return the result to the host thread after the task is executed. There is no context dependency. You can use the approach described in this topic. 4 5This example uses image loading to illustrate the process. 6 71. Implement the task to be executed in a child thread. 8 9 ```ts 10 // IconItemSource.ets 11 export class IconItemSource { 12 image: string | Resource = ''; 13 text: string | Resource = ''; 14 15 constructor(image: string | Resource = '', text: string | Resource = '') { 16 this.image = image; 17 this.text = text; 18 } 19 } 20 ``` 21 22 ```ts 23 // IndependentTask.ets 24 import { IconItemSource } from './IconItemSource'; 25 26 // Methods executed in the task must be decorated by @Concurrent. Otherwise, they cannot be called. 27 @Concurrent 28 export function loadPicture(count: number): IconItemSource[] { 29 let iconItemSourceList: IconItemSource[] = []; 30 // Add six IconItem data records. 31 for (let index = 0; index < count; index++) { 32 const numStart: number = index * 6; 33 // Use six images in the loop. 34 iconItemSourceList.push(new IconItemSource('$media:startIcon', `item${numStart + 1}`)); 35 iconItemSourceList.push(new IconItemSource('$media:background', `item${numStart + 2}`)); 36 iconItemSourceList.push(new IconItemSource('$media:foreground', `item${numStart + 3}`)); 37 iconItemSourceList.push(new IconItemSource('$media:startIcon', `item${numStart + 4}`)); 38 iconItemSourceList.push(new IconItemSource('$media:background', `item${numStart + 5}`)); 39 iconItemSourceList.push(new IconItemSource('$media:foreground', `item${numStart + 6}`)); 40 } 41 return iconItemSourceList; 42 } 43 ``` 44 452. Use the **execute** method of TaskPool to execute the task, that is, to load the images. 46 47 ```ts 48 // Index.ets 49 import { taskpool } from '@kit.ArkTS'; 50 import { IconItemSource } from './IconItemSource'; 51 import { loadPicture } from './IndependentTask'; 52 53 @Entry 54 @Component 55 struct Index { 56 @State message: string = 'Hello World'; 57 58 build() { 59 Row() { 60 Column() { 61 Text(this.message) 62 .fontSize(50) 63 .fontWeight(FontWeight.Bold) 64 .onClick(() => { 65 let iconItemSourceList: IconItemSource[] = []; 66 // Create a task. 67 let lodePictureTask: taskpool.Task = new taskpool.Task(loadPicture, 30); 68 // Execute the task and return the result. 69 taskpool.execute(lodePictureTask).then((res: object) => { 70 // Execution result of the loadPicture method. 71 iconItemSourceList = res as IconItemSource[]; 72 }) 73 }) 74 } 75 .width('100%') 76 } 77 .height('100%') 78 } 79 } 80 ``` 81