update zh-cn/application-dev/reference/apis/js-apis-pointer.md.

Signed-off-by: Nningning <3248127340@qq.com>

zh-cn/application-dev/reference/apis/js-apis-pointer.md

@@ -278,9 +278,12 @@ getPointerStyle(windowId: number, callback: AsyncCallback<PointerStyle>):
 ```js
 import window from '@ohos.window';
 
-window.getTopWindow((error, win) => {
-  win.getWindowProperties((error, properties) => {
-    let windowId = properties.id;
+window.getLastWindow(this.context, (error, win) => {
+  if (error.code) {
+    console.error('Failed to obtain the top window. Cause: ' + JSON.stringify(error));
+    return;
+  }
+  let windowId = win.getWindowProperties().id;
   if (windowId < 0) {
     console.log(`Invalid windowId`);
     return;
@@ -292,7 +295,6 @@ window.getTopWindow((error, win) => {
   } catch (error) {
     console.log(`Get pointer style failed, error: ${JSON.stringify(error, [`code`, `message`])}`);
   }
-  });
 });
 ```
 
@@ -321,9 +323,12 @@ getPointerStyle(windowId: number): Promise&lt;PointerStyle&gt;
 ```js
 import window from '@ohos.window';
 
-window.getTopWindow((error, win) => {
-  win.getWindowProperties((error, properties) => {
-    let windowId = properties.id;
+window.getLastWindow(this.context, (error, win) => {
+  if (error.code) {
+    console.error('Failed to obtain the top window. Cause: ' + JSON.stringify(error));
+    return;
+  }
+  let windowId = win.getWindowProperties().id;
   if (windowId < 0) {
     console.log(`Invalid windowId`);
     return;
@@ -335,7 +340,6 @@ window.getTopWindow((error, win) => {
   } catch (error) {
     console.log(`Get pointer style failed, error: ${JSON.stringify(error, [`code`, `message`])}`);
   }
-  });
 });
 ```
 
@@ -360,9 +364,12 @@ setPointerStyle(windowId: number, pointerStyle: PointerStyle, callback: AsyncCal
 ```js
 import window from '@ohos.window';
 
-window.getTopWindow((error, win) => {
-  win.getWindowProperties((error, properties) => {
-    let windowId = properties.id;
+window.getLastWindow(this.context, (error, win) => {
+  if (error.code) {
+    console.error('Failed to obtain the top window. Cause: ' + JSON.stringify(error));
+    return;
+  }
+  let windowId = win.getWindowProperties().id;
   if (windowId < 0) {
     console.log(`Invalid windowId`);
     return;
@@ -374,7 +381,6 @@ window.getTopWindow((error, win) => {
   } catch (error) {
     console.log(`Set pointer style failed, error: ${JSON.stringify(error, [`code`, `message`])}`);
   }
-  });
 });
 ```
 ## pointer.setPointerStyle<sup>9+</sup>
@@ -398,9 +404,12 @@ setPointerStyle(windowId: number, pointerStyle: PointerStyle): Promise&lt;void&g
 ```js
 import window from '@ohos.window';
 
-window.getTopWindow((error, win) => {
-  win.getWindowProperties((error, properties) => {
-    let windowId = properties.id;
+window.getLastWindow(this.context, (error, win) => {
+  if (error.code) {
+    console.error('Failed to obtain the top window. Cause: ' + JSON.stringify(error));
+    return;
+  }
+  let windowId = win.getWindowProperties().id;
   if (windowId < 0) {
     console.log(`Invalid windowId`);
     return;
@@ -412,7 +421,6 @@ window.getTopWindow((error, win) => {
   } catch (error) {
     console.log(`Set pointer style failed, error: ${JSON.stringify(error, [`code`, `message`])}`);
   }
-  });
 });
 ```
 ## PointerStyle<sup>9+</sup>