AppBase

#include "crosspad-gui/app/AppBase.hpp"

Generated from crosspad-gui/app/AppBase.hpp in crosspad-gui. Edit the header’s doxygen comments to change this page.

Recipes that use it: Hello screen, Tempo and transport, UI kit

Functions

`defaultAppFactory`

template <typename AppType>
std::shared_ptr< ILvglApp > defaultAppFactory(lv_obj_t *container, const char *name, const char *icon, lv_obj_t *(*create)(lv_obj_t *, AppType *), void(*destroy)(lv_obj_t *))

Default app factory — eliminates per-platform boilerplate.

Usage: config.app_factory = crosspad_gui::defaultAppFactory<App>;

Returns a std::shared_ptr so that AppType (which derives from std::enable_shared_from_this) can call shared_from_this() at runtime (required by destroyAppAsync()). Constructing via raw new would leave the internal weak_ptr unset and break shared_from_this().

Declared in crosspad-gui/app/AppBase.hpp:326.

Types

`crosspad_gui::AppBase`

Put cleanup in the destroy function or setOnDestroy; the IApp hooks it inherits (onAppInit, onAppDeinit, onAppUpdate, onAppActivated) are not part of the app lifecycle.

template <typename Derived>
class crosspad_gui::AppBase

CRTP base class for LVGL applications.

Provides the full LVGL lifecycle (start / pause / resume / destroyApp), flag management, and getter/setter boilerplate that would otherwise be duplicated across every platform’s App class.

Platform subclass example:

class App : public crosspad_gui::AppBase<App> {
public:
    using AppBase::AppBase;          // inherit constructors
    Sequencer& sequencer();          // platform-specific accessor
};
// Use crosspad::getPadManager() etc. directly from PlatformServices.

Used in Hello screen, Tempo and transport, UI kit.

Field	Type	Description
`app`	`lv_obj_t *`	This app’s root LVGL object.
`app_c`	`lv_obj_t *`	Parent container.
`parent_app`	`Derived *`	Parent app (for sub-apps)

Members

Member	Description
`AppBase`
`AppBase`
`getName`
`AddFlag`
`HasFlag`
`start`
`resume`	Platform only The framework calls it after `start()`.
`setSelfRef`	Set by the app factory so a deferred self-close can hold the app alive until the callback runs.
`destroyAppAsync`	Close this app from inside itself.
`destroyApp`
`setOnShow`
`setOnBack`	Optional in-app handler for the power button’s short click.
`setOnDestroy`
`setPadLogicName`	Declarative pad logic: name auto-activated on start() and restored on destroyApp().
`getAppContainer`
`getIcon`
`isVisible`
`isStarted`
`handleBack`	Contextual “back” gesture (the power button’s short click) offered to the app before the framework closes it.

Methods

`AppBase`

AppBase(lv_obj_t *app_c, const char *name, const char *icon, CreateFn create, DestroyFn destroy=lv_Default_onDestroy)

`AppBase`

AppBase(Derived *parent, const char *name, const char *icon, CreateFn create, DestroyFn destroy=lv_Default_onDestroy)

`getName`

const char * getName() const override

`AddFlag`

virtual void AddFlag(AppFlags flag) override

`HasFlag`

virtual bool HasFlag(AppFlags flag) override

`start`

virtual void start(lv_obj_t *parent=lv_screen_active()) override

`resume`

Platform only The framework calls it after start().

virtual void resume() override

`setSelfRef`

virtual void setSelfRef(std::weak_ptr< ILvglApp > self) override

Set by the app factory so a deferred self-close can hold the app alive until the callback runs.

Default no-op for hand-built implementations.

`destroyAppAsync`

virtual void destroyAppAsync() override

Close this app from inside itself.

Deferring matters: a Back button calls this from an LVGL event callback of a widget that destroyApp() is about to delete, and LVGL must not delete the object whose event it is dispatching.

Used in Hello screen.

`destroyApp`

virtual void destroyApp() override

`setOnShow`

void setOnShow(ShowFn show)

`setOnBack`

void setOnBack(BackFn back)

Optional in-app handler for the power button’s short click.

Without one the gesture closes the app (destroyAppAsync).

Used in Hello screen.

`setOnDestroy`

void setOnDestroy(DestroyFn dest)

`setPadLogicName`

virtual void setPadLogicName(const char *name) override

Declarative pad logic: name auto-activated on start() and restored on destroyApp().

Default no-op so non-AppBase implementers are unaffected.

`getAppContainer`

virtual lv_obj_t * getAppContainer() override

`getIcon`

virtual const char * getIcon() override

`isVisible`

bool isVisible()

`isStarted`

virtual bool isStarted() override

`handleBack`

virtual bool handleBack() override

Contextual “back” gesture (the power button’s short click) offered to the app before the framework closes it.

Return true if the app consumed it — e.g. it stepped out of its own sub-view. Default false: the framework then returns to the launcher.

Declared in crosspad-gui/app/AppBase.hpp:38.