1# @ohos.app.ability.AbilityStage (AbilityStage) 2 3**AbilityStage** is a runtime class for HAP files. 4 5**AbilityStage** notifies you of when you can perform HAP initialization such as resource pre-loading and thread creation during the HAP loading. 6 7> **NOTE** 8> 9> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version. 10> The APIs of this module can be used only in the stage model. 11 12## Modules to Import 13 14```ts 15import AbilityStage from '@ohos.app.ability.AbilityStage'; 16``` 17 18## AbilityStage.onCreate 19 20onCreate(): void 21 22Called when the application is created. 23 24**System capability**: SystemCapability.Ability.AbilityRuntime.Core 25 26**Example** 27 28```ts 29import AbilityStage from '@ohos.app.ability.AbilityStage'; 30 31class MyAbilityStage extends AbilityStage { 32 onCreate() { 33 console.log('MyAbilityStage.onCreate is called'); 34 } 35} 36``` 37 38 39## AbilityStage.onAcceptWant 40 41onAcceptWant(want: Want): string; 42 43Called when a specified ability is started. 44 45**System capability**: SystemCapability.Ability.AbilityRuntime.Core 46 47**Parameters** 48 49| Name| Type| Mandatory| Description| 50| -------- | -------- | -------- | -------- | 51| want | [Want](js-apis-app-ability-want.md) | Yes| Want information about the target ability, such as the ability name and bundle name.| 52 53**Return value** 54 55 | Type| Description| 56 | -------- | -------- | 57 | string | Returns an ability ID. If this ability has been started, no new instance is created and the ability is placed at the top of the stack. Otherwise, a new instance is created and started.| 58 59**Example** 60 61```ts 62import AbilityStage from '@ohos.app.ability.AbilityStage'; 63import Want from '@ohos.app.ability.Want'; 64 65class MyAbilityStage extends AbilityStage { 66 onAcceptWant(want: Want) { 67 console.log('MyAbilityStage.onAcceptWant called'); 68 return 'com.example.test'; 69 } 70} 71``` 72 73 74## AbilityStage.onConfigurationUpdate 75 76onConfigurationUpdate(newConfig: Configuration): void; 77 78Called when the global configuration is updated. 79 80**System capability**: SystemCapability.Ability.AbilityRuntime.Core 81 82**Parameters** 83 84 | Name| Type| Mandatory| Description| 85 | -------- | -------- | -------- | -------- | 86 | newConfig | [Configuration](js-apis-app-ability-configuration.md) | Yes| Callback invoked when the global configuration is updated. The global configuration indicates the configuration of the environment where the application is running and includes the language and color mode.| 87 88**Example** 89 90```ts 91import AbilityStage from '@ohos.app.ability.AbilityStage'; 92import { Configuration } from '@ohos.app.ability.Configuration'; 93 94class MyAbilityStage extends AbilityStage { 95 onConfigurationUpdate(config: Configuration) { 96 console.log('onConfigurationUpdate, language: ${config.language}'); 97 } 98} 99``` 100 101## AbilityStage.onMemoryLevel 102 103onMemoryLevel(level: AbilityConstant.MemoryLevel): void; 104 105Called when the system has decided to adjust the memory level. For example, this API can be used when there is not enough memory to run as many background processes as possible. 106 107**System capability**: SystemCapability.Ability.AbilityRuntime.Core 108 109**Parameters** 110 111 | Name| Type| Mandatory| Description| 112 | -------- | -------- | -------- | -------- | 113 | level | [AbilityConstant.MemoryLevel](js-apis-app-ability-abilityConstant.md#abilityconstantmemorylevel) | Yes| Memory level that indicates the memory usage status. When the specified memory level is reached, a callback will be invoked and the system will start adjustment.| 114 115**Example** 116 117```ts 118import AbilityStage from '@ohos.app.ability.AbilityStage'; 119import AbilityConstant from '@ohos.app.ability.AbilityConstant'; 120 121class MyAbilityStage extends AbilityStage { 122 onMemoryLevel(level: AbilityConstant.MemoryLevel) { 123 console.log(`onMemoryLevel, level: ${JSON.stringify(level)}`); 124 } 125} 126``` 127 128## AbilityStage.context 129 130context: AbilityStageContext; 131 132Defines the context of **AbilityStage**. 133 134**System capability**: SystemCapability.Ability.AbilityRuntime.Core 135 136| Name | Type | Description | 137| ----------- | --------------------------- | ------------------------------------------------------------ | 138| context | [AbilityStageContext](js-apis-inner-application-abilityStageContext.md) | The context is obtained in the callback invoked when initialization is performed during ability startup.| 139