ArkTS會(huì)對(duì)自定義組件的成員變量使用的訪問(wèn)限定符private/public/protected進(jìn)行校驗(yàn)，當(dāng)不按規(guī)范使用訪問(wèn)限定符private/public/protected時(shí)，會(huì)產(chǎn)生對(duì)應(yīng)的日志信息。

說(shuō)明：
從API version 12開始，支持自定義組件成員屬性訪問(wèn)限定符使用限制的規(guī)則。

使用限制

• 對(duì)于@State/@Prop/@Provide/@BuilderParam/常規(guī)成員變量(不涉及更新的普通變量)，當(dāng)使用private修飾時(shí)，在自定義組件構(gòu)造時(shí)，不允許進(jìn)行賦值傳參，否則會(huì)有編譯告警日志提示。

• 對(duì)于@StorageLink/@StorageProp/@LocalStorageLink/@LocalStorageLink/@Consume變量，當(dāng)使用public修飾時(shí)，會(huì)有編譯告警日志提示。

• 對(duì)于@Link/@ObjectLink變量，當(dāng)使用private修飾時(shí)，會(huì)有編譯告警日志提示。

• 由于struct沒(méi)有繼承能力，上述所有的這些變量使用protected修飾時(shí)，會(huì)有編譯告警日志提示。

• 當(dāng)@Require和private同時(shí)修飾自定義組件struct的@State/@Prop/@Provide/@BuilderParam/常規(guī)成員變量(不涉及更新的普通變量)時(shí)，會(huì)有編譯告警日志提示。

錯(cuò)誤使用場(chǎng)景示例

1.當(dāng)成員變量被private訪問(wèn)限定符和@State/@Prop/@Provide/@BuilderParam裝飾器同時(shí)修飾時(shí)，ArkTS會(huì)進(jìn)行校驗(yàn)并產(chǎn)生告警日志。

@Entry
@Component
struct AccessRestrictions {
  @Builder buildTest() {
    Text("Parent builder")
  }
  build() {
    Column() {
      ComponentsChild({state_value: "Hello", prop_value: "Hello", provide_value: "Hello", builder_value: this.buildTest, regular_value: "Hello"})
    }
    .width('100%')
  }
}

@Component
struct ComponentsChild {
  @State private state_value: string = "Hello";
  @Prop private prop_value: string = "Hello";
  @Provide private provide_value: string = "Hello";
  @BuilderParam private builder_value: () => void = this.buildTest;
  private regular_value: string = "Hello";
  @Builder buildTest() {
    Text("Child builder")
  }
  build() {
    Column() {
      Text("Hello")
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
    }
  }
}

編譯告警日志如下：

Property 'state_value' is private and can not be initialized through the component constructor.
Property 'prop_value' is private and can not be initialized through the component constructor.
Property 'provide_value' is private and can not be initialized through the component constructor.
Property 'builder_value' is private and can not be initialized through the component constructor.
Property 'regular_value' is private and can not be initialized through the component constructor.

2.當(dāng)成員變量被public訪問(wèn)限定符和@StorageLink/@StorageProp/@LocalStorageLink/@LocalStorageLink/@Consume裝飾器同時(shí)修飾時(shí)，ArkTS會(huì)進(jìn)行校驗(yàn)并產(chǎn)生告警日志。

@Entry
@Component
struct AccessRestrictions {
  @Provide consume_value: string = "Hello";
  build() {
    Column() {
      ComponentChild()
    }
    .width('100%')
  }
}

@Component
struct ComponentChild {
  @LocalStorageProp("sessionLocalProp") public local_prop_value: string = "Hello";
  @LocalStorageLink("sessionLocalLink") public local_link_value: string = "Hello";
  @StorageProp("sessionProp") public storage_prop_value: string = "Hello";
  @StorageLink("sessionLink") public storage_link_value: string = "Hello";
  @Consume public consume_value: string;
  build() {
    Column() {
      Text("Hello")
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
    }
  }
}

編譯告警日志如下：

Property 'local_prop_value' can not be decorated with both @LocalStorageProp and public.
Property 'local_link_value' can not be decorated with both @LocalStorageLink and public.
Property 'storage_prop_value' can not be decorated with both @StorageProp and public.
Property 'storage_link_value' can not be decorated with both @StorageLink and public.
Property 'consume_value' can not be decorated with both @Consume and public.

3.當(dāng)成員變量被private訪問(wèn)限定符和@Link/@ObjectLink裝飾器同時(shí)修飾時(shí)，ArkTS會(huì)進(jìn)行校驗(yàn)并產(chǎn)生告警日志。

@Entry
@Component
struct AccessRestrictions {
  @State link_value: string = "Hello";
  @State objectLink_value: ComponentObj = new ComponentObj();
  build() {
    Column() {
      ComponentChild({link_value: this.link_value, objectLink_value: this.objectLink_value})
    }
    .width('100%')
  }
}

@Observed
class ComponentObj {
  count: number = 0;
}
@Component
struct ComponentChild {
  @Link private link_value: string;
  @ObjectLink private objectLink_value: ComponentObj;
  build() {
    Column() {
      Text("Hello")
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
    }
  }
}

編譯告警日志如下：

Property 'link_value' can not be decorated with both @Link and private.
Property 'objectLink_value' can not be decorated with both @ObjectLink and private.

4.當(dāng)成員變量被protected訪問(wèn)限定符修飾時(shí)，ArkTS會(huì)進(jìn)行校驗(yàn)并產(chǎn)生告警日志。

@Entry
@Component
struct AccessRestrictions {
  build() {
    Column() {
      ComponentChild({regular_value: "Hello"})
    }
    .width('100%')
  }
}

@Component
struct ComponentChild {
  protected regular_value: string = "Hello";
  build() {
    Column() {
      Text("Hello")
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
    }
  }
}

編譯告警日志如下：

The member attributes of a struct can not be protected.

5.當(dāng)成員變量被private訪問(wèn)限定符、@Require和@State/@Prop/@Provide/@BuilderParam裝飾器同時(shí)修飾時(shí)，ArkTS會(huì)進(jìn)行校驗(yàn)并產(chǎn)生告警日志。

@Entry
@Component
struct AccessRestrictions {
  build() {
    Column() {
      ComponentChild({prop_value: "Hello"})
    }
    .width('100%')
  }
}
@Component
struct ComponentChild {
  @Require @Prop private prop_value: string = "Hello";
  build() {
    Column() {
      Text("Hello")
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
    }
  }
}

編譯告警日志如下：

Property 'prop_value' can not be decorated with both @Require and private.
Property 'prop_value' is private and can not be initialized through the component constructor.

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