Qt Quick Ultralite maintains source compatibility between minor releases. However, some changes may require you to adapt the application code accordingly. The following sections highlight such changes:

Changes in 1.4

Important changes

• Qt for MCUs now requires a compiler supporting the C++14 standard. This affects both Qt for MCUs source code and application code (C++ code generated from QML).
• The build system has been restructured. The OS is now part of the platform name instead of a CMake configure option. For example, to configure your project for STM32F769i-discovery and FreeRTOS, you can now pass -DQUL_PLATFORM=stm32f769i-discovery-freertos to CMake instead of -DQUL_PLATFORM=stm32f769i-discovery -DOS=FreeRTOS. In addition, platform-specific CMake files are moved from lib/cmake/Qul/boards to the source folder of each platform: src/platform/boards/<board_name>/cmake.
• As part of the build system restructure, the platform code is organized into a separate library to enable porting to new boards witout rebuilding the core library. All platform code was move out of the src folder to platform

New features

• The Monotype iType Spark font engine is available as Technology Preview. It must be enabled explicitly to replace the default static font engine. This new font engine can reduce the memory footprint considerably, especially when the application uses multiple fonts and/or languages. For more information, see Text Rendering and Fonts.
• Timeline can now animate alias properties.
• Transitions may now contain animations for properties that are not mentioned in PropertyChanges for the state.
• The properties representing the red, blue, green, and alpha components of a color can be assigned values explicitly.

Source compatibility breaks

• FREERTOS_CONFIG_DIR target property is removed as the applications must use the same version used in the FreeRTOS platform package.
• Heap allocators in FreeRTOS are not initialized anymore. Applications must handle the initialization.
• Transitions no longer override the from and to values of the PropertyAnimation.

Fixed issues

• Enabled support for a delegate Component to be used by multiple views.
• Fixed comparison of concatenated strings incorrectly returning false.
• As in Qt Quick, the Animation.loops property accepts a negative number (in addition to Animation.Infinite) to animate continuously.

New APIs

New CMake API