Defining Singletons in QML Internationalization and Localization with Qt Quick Ultralite

C

Entry point to Qt Quick Ultralite application

Initializing Qt Quick Ultralite from `main()`

It's up to application developer on how and when hardware initialization is done. Typically it's done by calling Qul::initHardware() just before Qul::initPlatform(), but developer may also decide not call it and perform own hardware initialization.

To start the graphical part of your application you need to call Qul::initPlatform(), create a Qul::Application object in your main() or a task function and then call the Qul::Application::exec() function.

Qul::initPlatform() initializes Qt Quick Ultralite platform components and the event loop starts when you call Qul::Application::exec().

For example, if the main item defined in QML is called MainScreen, main.cpp on bare metal could contain the following:

#include "MainScreen.h"

#include <qul/application.h>
#include <qul/qul.h>

int main()
{
    Qul::initHardware();
    Qul::initPlatform();
    Qul::Application app;
    static MainScreen item;
    app.setRootItem(&item);
    while (true) {
        uint64_t now = Qul::Platform::getPlatformInstance()->currentTimestamp();
        // <handle timers>
        uint64_t nextUpdate = app.update();
        if (nextUpdate > now) {
            // Device can go to sleep until next update is due

            // enterLowPowerMode(nextUpdate - now);
        }
    }
    return 1;
}

Or when using FreeRTOS main.cpp could be:

#include "MainScreen.h"

#include <qul/application.h>
#include <qul/qul.h>
#include <platforminterface/log.h>

#include <FreeRTOS.h>
#include <task.h>

#ifndef QUL_STACK_SIZE
#error QUL_STACK_SIZE must be defined.
#endif

static void Qul_Thread(void *argument);
// extern const HeapRegion_t xHeapRegions[]; // HeapRegion for FreeRTOS Heap_5

int main()
{
    Qul::initHardware();
    // vPortDefineHeapRegions(xHeapRegions); // Initialize FreeRTOS Heap_5
    Qul::initPlatform();

    if (xTaskCreate(Qul_Thread, "QulExec", QUL_STACK_SIZE, 0, 4, 0) != pdPASS) {
        Qul::PlatformInterface::log("Task creation failed!.\r\n");
        configASSERT(false);
    }

    vTaskStartScheduler();

    // Should not reach this point
    return 1;
}

static void Qul_Thread(void *argument)
{
    Qul::Application app;
    static MainScreen item;
    app.setRootItem(&item);
    while (true)
        app.update();
}

Note: FreeRTOS Heap_5 must be initialized before calling Qul::initPlatform().

To configure text cache for your application, call the appropriate Qul::Application constructor in main.app, as shown in the following example:

#include "MainScreen.h"

#include <qul/application.h>
#include <qul/qul.h>

int main()
{
    Qul::initHardware();
    Qul::initPlatform();

    Qul::ApplicationConfiguration appConfig;
    appConfig.setTextCacheEnabled(true);
    appConfig.setTextCacheSize(128 * 1024);
    Qul::Application app(appConfig);

    static MainScreen item;
    app.setRootItem(&item);
    while (true) {
        uint64_t now = Qul::Platform::getPlatformInstance()->currentTimestamp();
        // <handle timers>
        uint64_t nextUpdate = app.update();
        if (nextUpdate > now) {
            // Device can go to sleep until next update is due

            // enterLowPowerMode(nextUpdate - now);
        }
    }
    return 1;
}

And, similarly for FreeRTOS:

#include "MainScreen.h"

#include <qul/application.h>
#include <qul/qul.h>
#include <platforminterface/log.h>

#include <FreeRTOS.h>
#include <task.h>

#ifndef QUL_STACK_SIZE
#error QUL_STACK_SIZE must be defined.
#endif

static void Qul_Thread(void *argument);
// extern const HeapRegion_t xHeapRegions[]; // HeapRegion for FreeRTOS Heap_5

int main()
{
    Qul::initHardware();
    // vPortDefineHeapRegions(xHeapRegions); // Initialize FreeRTOS Heap_5
    Qul::initPlatform();

    if (xTaskCreate(Qul_Thread, "QulExec", QUL_STACK_SIZE, 0, 4, 0) != pdPASS) {
        Qul::PlatformInterface::log("Task creation failed!.\r\n");
        configASSERT(false);
    }

    vTaskStartScheduler();

    // Should not reach this point
    return 1;
}

static void Qul_Thread(void *argument)
{
    Qul::ApplicationConfiguration appConfig;
    appConfig.setTextCacheEnabled(true);
    appConfig.setTextCacheSize(64 * 1024);
    Qul::Application app(appConfig);

    static MainScreen item;
    app.setRootItem(&item);
    while (true)
        app.update();
}

Defining Singletons in QML Internationalization and Localization with Qt Quick Ultralite

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C

Entry point to Qt Quick Ultralite application

Initializing Qt Quick Ultralite from main()

Initializing Qt Quick Ultralite from `main()`