1# Lifecycle 2 3 4## Application Lifecycle 5 6You can define the following application lifecycle functions in the app.js file. 7 8 | Attribute | Type | Description | Called When | 9| -------- | -------- | -------- | -------- | 10| onCreate | () => void | Listens for application creation. | The application is created. | 11| onShow<sup>6+</sup> | () => void | Listens for whether the application is running in the foreground. | The application is running in the foreground. | 12| onHide<sup>6+</sup> | () => void | Listens for whether the application is running in the background. | The application is running in the background. | 13| onDestroy | () => void | Listens for application uninstallation. | The application exits. | 14 15## Page Lifecycle 16 17You can define the following page lifecycle functions in the .js file of the page. 18 19| Attribute | Type | Description | Called When | 20| -------- | -------- | -------- | -------- | 21| onInit | () => void | Listens for page initialization. | Page initialization is complete. This function is called only once in the page lifecycle. | 22| onReady | () => void | Listens for page creation. | A page is created. This function is called only once in the page lifecycle. | 23| onShow | () => void | Listens for page display. | The page is displayed. | 24| onHide | () => void | Listens for page disappearance. | The page disappears. | 25| onDestroy | () => void | Listens for page destruction. | The page is destroyed. | 26| onBackPress | () => boolean | Listens for the back button action. | The back button is touched.<br/>- true means that the page processes the return logic.<br/>- false means that the default return logic is used.<br/>- If no value is returned, the default return logic is used. | 27| onActive()<sup>5+</sup> | () => void | Listens for page activation. | The page is activated. | 28| onInactive()<sup>5+</sup> | () => void | Listens for page suspension. | The page is suspended. | 29| onNewRequest()<sup>5+</sup> | () => void | Listens for a new FA request. | The FA has been started and a new request is received. | 30 31 The lifecycle functions of page A are called in the following sequence: 32- Open page A: onInit() -> onReady() -> onShow() 33 34- Open page B on page A: onHide() 35 36- Go back to page A from page B: onShow() 37 38- Exit page A: onBackPress() -> onHide() -> onDestroy() 39 40- Hide page A: onInactive() -> onHide() 41 42- Show background page A on the foreground: onShow() -> onActive() 43 44 45 46
