From 58852cf6a4796d84d7950e7b57b9829a1fb294b2 Mon Sep 17 00:00:00 2001
From: xu <chenxu25@huawei.com>
Date: Wed, 14 Sep 2022 15:40:41 +0800
Subject: [PATCH] =?UTF-8?q?=E6=96=B0=E5=A2=9E=E6=BB=91=E5=8A=A8=E7=99=BD?=
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Signed-off-by: xu <chenxu25@huawei.com>
---
 ...-performance-improvement-recommendation.md | 43 ++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/zh-cn/application-dev/ui/ts-performance-improvement-recommendation.md b/zh-cn/application-dev/ui/ts-performance-improvement-recommendation.md
index b20f704d11..e37724ed2f 100644
--- a/zh-cn/application-dev/ui/ts-performance-improvement-recommendation.md
+++ b/zh-cn/application-dev/ui/ts-performance-improvement-recommendation.md
@@ -257,4 +257,45 @@ struct MyComponent {
     }.backgroundColor(Color.Pink)
   }
 }
-```
\ No newline at end of file
+```
+
+## 减少应用滑动白块
+应用通过增大List/Grid控件的cachedCount参数，调整UI的加载范围。cachedCount表示屏幕外List/Grid预加载item的个数。  
+如果需要请求网络图片，可以在item滑动到屏幕显示之前，提前下载好内容，从而减少滑动白块。  
+如下是使用cachedCount参数的例子：
+
+```ts
+@Entry
+@Component
+struct MyComponent {
+  private source: MyDataSource = new MyDataSource();
+  build() {
+    List() {
+      LazyForEach (this.source, item => {
+        ListItem() {
+          Text("Hello" + item)
+            .fontSize(100)
+            .onAppear(()=>{
+              console.log("appear:" + item)
+            })
+        }
+      })
+    }.cachedCount(3)  // 扩大数值appear日志范围会变大
+  }
+}
+class MyDataSource implements IDataSource {
+  data: number[] = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15];
+  public totalCount(): number {
+    return this.data.length
+  }
+  public getData(index: number): any {
+    return this.data[index]
+  }
+  registerDataChangeListener(listener: DataChangeListener): void {
+  }
+  unregisterDataChangeListener(listener: DataChangeListener): void {
+  }
+}
+```
+**使用说明：**
+cachedCount的增加会增大UI的cpu、内存开销。使用时需要根据实际情况，综合性能和用户体验进行调整。
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-- 
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