HarmonyOS 鸿蒙Next 为什么这个图片取色取得颜色一

HarmonyOS 鸿蒙Next 为什么这个图片取色取得颜色一

import image from '@ohos.multimedia.image';
import effectKit from '@ohos.effectKit';
import resourceManager from '@ohos.resourceManager';

// 初始背景色赋值
@State bgColor: string = "#F64D47";
// 顶部安全高度赋值
@State topSafeHeight: number = 0;
@State shColor: Color = Color.White;
@State sizeDate: number = 20;
@State rVal: number = 255;
@State gVal: number = 255;
@State bVal: number = 255;
@State aVal: number = 0.4;
@State rad: number = 40;
@State satVal: number = 0.8;
@State briVal: number = 1.5;

async aboutToAppear() {
  // 顶部安全高度适配
  // let windowHeight: window.Window = await window.getLastWindow(getContext(this));
  // await windowHeight.setWindowLayoutFullScreen(true);
  // this.topSafeHeight = px2vp(windowHeight.getWindowAvoidArea(window.AvoidAreaType.TYPE_SYSTEM).topRect.height)

  // TODO 知识点：初始化页面获取第一张图片的颜色
  const context = getContext(this);
  const resourceMgr: resourceManager.ResourceManager = context.resourceManager;
  const fileData: Uint8Array = await resourceMgr.getMediaContent(this.imgData[0]);
  const buffer = fileData.buffer as ArrayBuffer;
  const imageSource: image.ImageSource = image.createImageSource(buffer);
  const pixelMap: image.PixelMap = await imageSource.createPixelMap();

  // TODO 知识点：智能取色器接口使用，初始化背景色
  effectKit.createColorPicker(pixelMap, (err, colorPicker) => {
    let color = colorPicker.getMainColorSync();
    // 将取色器选取的color示例转换为十六进制颜色代码
    this.bgColor = "#" + color.alpha.toString(16) + color.red.toString(16) + color.green.toString(16) + color.blue.toString(16)

    console.info('===初始化页面获取第一张图片的颜色==', this.bgColor)
  })
}

用的api11，我想在swiper 里面实时取到图片的颜色 更改背景色 但是现在无论是初始化还是 轮播图滚动后颜色一直都是"#000"。

求大佬解答