Common Widget FeaturesΒΆ The following details apply to all types of Widgets. Widget Basics What is a Widget? Attributes Basic attributes Widget-specific attributes Parents and children Working Mechanisms Parent-child structure Moving together Visibility only on the parent Creating and deleting Widgets Screens What are Screens? Creating Screens Active Screen Loading Screens Layers Parts States Flags Base-Widget Events Events from Input Devices Special Events Drawing Events Other Events Keys Names Setting names Finding widgets Snapshot Example Base objects with custom styles Make an object draggable Transform object using a 3x3 matrix API Positions, Sizes and Layouts Overview Length Units Boxing Model Important Notes Postponed coordinate calculation Removing styles Positioning Widgets Direct Alignment Size Sizing the simple way Extending the click area Using styles Translation Transformation Min and Max size Layout Layout overview Built-in layouts Flags Adding new layouts Examples API Layers Order of Creation Changing Order API Styles Styles Overview States Cascading Styles Inheritance Parts Initialize Styles and Set/Get Properties Add and remove styles to a widget Local Styles Style Properties Overview Transitions Opacity, Blend Modes and Transformations Color Filter Themes Examples API Style Properties Size and position Padding Margin Background Border Outline Shadow Image Line Arc Text Miscellaneous Flex Grid Events Adding Events to a Widget Removing Event(s) from Widgets Event Codes Input Device Events Drawing Events Special Events Other Events Display Events Custom Events Refresh Event Sending Events Manually Fields of lv_event_t Event Bubbling Examples Button click event Click streaks Handle multiple events Event bubbling Draw event API Layouts Flex Overview Terms Simple Interface Style Interface Other Features Examples API Grid Overview Terms Simple Interface Style Interface Other features Example API Scrolling Overview Scrollbar Scrolling Events Features of Scrolling Scrollable Scroll chaining Scroll momentum Elastic scroll Snapping Scroll one Scroll on focus Scrolling Programmatically Self Size Examples Nested scrolling Snapping Floating button Styling the scrollbars Right to left scrolling Translate on scroll Infinite scrolling circular scrolling API