# Ability Framework Development ## Is a guide similar to the Data ability development in the FA model available for the stage model? Applicable to: OpenHarmony SDK 3.2.3.5, stage model of API version 9 A guide is available for the **DataShareExtensionAbility** class in the stage model, which provides APIs for sharing data with other applications and managing the data. Reference: [DataShare Development](../database/database-datashare-guidelines.md) ## What should I do if the UI does not respond when an ability is started? Applicable to: OpenHarmony SDK 3.2.5.3, stage model of API version 9 1. If the ability is started using **startAbility**, check whether the **abilityName** field in **want** uses the bundle name as the prefix. If yes, delete the bundle name. 2. Make sure the ability's home page file configured by **onWindowStageCreate** in the **MainAbility.ts** file is defined in the **main_pages.json** file. 3. You are advised to use the SDK and OpenHarmony SDK versions released on the same day. Reference: [Release Testing Version](https://gitee.com/openharmony-sig/oh-inner-release-management/blob/master/Release-Testing-Version.md) ## How do I prevent "this" in a method from changing to "undefined" when the method is called? Applicable to: OpenHarmony SDK 3.2.5.3, stage model of API version 9 Method 1: Add **.bind(this)** when calling the method. Method 2: Use the arrow function. ## What should I do when the message "must have required property 'startWindowIcon'" is displayed? Applicable to: OpenHarmony SDK 3.2.3.5, stage model of API version 9 Configure the **startWindowIcon** attribute under **abilities** in the **module.json5** file. Reference: [Application Package Structure Configuration File](../quick-start/stage-structure.md) Example: ``` { "module": { // Do something. "abilities": [{ // Do something. "startWindowIcon": "$media:space", "startWindowBackground": "$color:white", }] } } ``` ## How do I obtain a notification when the device orientation changes? Applicable to: OpenHarmony SDK 3.2.3.5, stage model of API version 9 Implement the **onConfigurationUpdated** callback in the **Ability** class. The callback is triggered when the system language, color mode, or display parameters (such as the orientation and density) change. Reference: [Ability Development](../ability/stage-ability.md)