修复自定义下载失败无失败回调以及新增全局自定义下载接口

Signed-off-by: zgf <zenggaofeng2@h-partners.com>

entry/src/main/ets/pages/LoadStatePage.ets

@@ -36,6 +36,10 @@ struct LoadStatePage {
     },
     border: { radius: 50 }
   }
+  @State imageKnifeOption1: ImageKnifeOption = {
+    loadSrc: $r('app.media.startIcon')
+  }
+  @State message: string = ""
   @State currentWidth: number = 200
   @State currentHeight: number = 200
   @State typeValue: string = ""
@@ -78,11 +82,33 @@ struct LoadStatePage {
       Text(this.typeValue)
       ImageKnifeComponent({ imageKnifeOption: this.ImageKnifeOption }).height(this.currentHeight).width(this.currentWidth)
         .margin({ top: 20 })
-
+      Button("自定义下载失败").onClick(()=>{
+        this.imageKnifeOption1 = {
+          loadSrc: "abc",
+          placeholderSrc:$r('app.media.loading'),
+          errorholderSrc:$r('app.media.failed'),
+          customImage:custom,
+          onLoadListener: {
+            onLoadFailed:(err)=>{
+              this.message = "err:" + err
+            }
+          }
+        }
+      }).margin({ top: 20 })
+      Text(this.message).fontSize(20).margin({ top: 20 })
+      ImageKnifeComponent({ imageKnifeOption: this.imageKnifeOption1 }).height(this.currentHeight).width(this.currentWidth)
+        .margin({ top: 20 })
     }
 
     .width('100%')
     .height('100%')
   }
 
+}
+// 自定义下载方法
+@Concurrent
+async function custom(context: Context, src: string | PixelMap | Resource): Promise<ArrayBuffer | undefined> {
+  console.info("ImageKnife::  custom download：" + src)
+  // 举例写死从本地文件读取，也可以自己请求网络图片
+  return undefined
 }