ImageKnife提供图片加载成功失败的事件README补充

Signed-off-by: 任伟x <renwei79@h-partners.com>

README.md

@@ -148,6 +148,29 @@ ImageKnifeComponent({ ImageKnifeOption:
 }).width(100).height(100)
 ```
 
+#### 8.监听图片加载成功与失败
+
+```
+ImageKnifeComponent({ ImageKnifeOption: 
+{
+   loadSrc: $r("app.media.rabbit"),
+   onLoadListener:{
+    onLoadStart:()=>{
+     this.starTime = new Date().getTime()
+     console.info("Load start: ");
+    },
+    onLoadFailed: (err) => {
+     console.error("Load Failed Reason: " + err + "  cost " + (new Date().getTime() - this.starTime) + " milliseconds");
+    },
+    onLoadSuccess: (data) => {
+     console.info("Load Successful: cost " + (new Date().getTime() - this.starTime) + " milliseconds");
+     return data;
+    },
+   }
+  }
+}).width(100).height(100)
+```
+
 ## 接口说明
 
 ### ImageKnifeOption参数列表