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:

Important changes

Removed options from platformexporter

The following command-line options are removed from the from the platform exporter tool and similar options are added to the qmlprojectexporter instead:

For more information about exporting a platform using the qmlprojectexporter, see Exporting a Qt for MCUs project with platform sources.

New features

• Reduce memory footprint of generated code by using static const arrays and loops to set constant property values.
• Optimize image assets by rotating them before based on the display rotation angle, avoiding the overhead of rotating them at runtime.
• Added support for acquiring licenses from the license servers.
• Upgrades:
  • STM32F469-Discovery SDK v1.28.0.
  • MIMXRT1050-EVK, MIMXRT1060-EVK, MIMXRT1064-EVK, and MIMXRT1170-EVKB SDK v2.15.000.
  • ARMGCC compiler 12.3.rel1.
  • Embedded Template Library (ETL) v20.38.10.
  • Renesas RA6 and RA8 FSP to 5.2.0.
  • FreeRTOS v10.6.1 on Renesas EK-RA6M3G.
  • TRAVEO™ T2G Cluster Series to graphics driver V2.3.0.
  • FreeType version 2.13.2.
  • Monotype Fontmap editor version 3.1.1.
• Added Monotype FontmapEditor support to reduce the font file size by removing the unused glyphs.
• Added the QtQuick.Layouts module with GridLayout QML type.
• qmlprojectexporter:
  • Added --parallel and -j command-line options to parallel process the QML files.
  • Added CMSIS pack generator to enable generating a package of the platform sources.
  • Extended support for CMake projects to include the complete application either with or without the platform sources.
• Added support for hardware accelerated JPEG decoding for Traveo T2G (6M).
• Added support for Traveo T2G 4M Lite.
• Added bitwise operator support to qmltocpp, enabling the use of bitwise OR (|) operator in QML.
• Added virtual keyboard support with the QtQuick.VirtualKeyboard module (Technology Preview).

Fixed issues

Qt for MCUs v2.8.1

• Fixed screen flickering artifacts on the STM32F769I-DISCOVERY and STM32H750B-DISCOVERY boards caused by LTDC underruns if the FMC controller is blocked.
• Fixed qulrcc to estimate correct resource cache size for sprite animations.
• Fixed error using certain TrueType fonts with the Spark font engine.
• Fixed potential compile error about incomplete type when sub-classing PaintedItemDelegate.
• Optimized the rendering stack to pre-rotate alpha maps when screen rotation is enabled. This avoids the need to rotate and blend alpha maps at runtime.
• Fixed the platform port for Infineon TRAVEO™ T2G, to avoid delaying layer animation if refresh intervals is too high.
• Fixed animation logic to avoid restarting running animations on calling start().
• qmltocpp fixes:
  • Use the same convention as lupdate to extract the context name for translatable units in the *.ui.qml files.
  • Generate correct C++ code for ScriptAction instances within the scope of a Loader or lRepeater.
  • Remove unnecessary call to update() while generating code for StaticText instances.
• qmlprojectexporter fixes:
  • Add --parallel and -j command-line options to parallel process the QML files. You can also define the no. of parallel jobs using the CMAKE_BUILD_PARALLEL_LEVEL environment variable.
  • Fix crash due to resourceCompression enabled in a module qmlproject file and not in the main qmlproject file.

Qt for MCUs v2.8.0

• Fixes to the fontcompiler:
  • Generate quality glyph alphamaps on both Linux and Windows hosts.
  • Reduce QulFontResourceData size slightly.
• Fixes to qmltocpp:
  • Fix crash on accessing object aliases from other QML files.
  • Improve anchor binding inside the inline component when it is used as a sourceComponent for Loader.
  • Check if a custom property of type Component is used as a binding for Loader::{souceComponent} to avoid a crash.
  • Make parent property available to the inline component declaration object to avoid a crash.
  • Qualify type with its module name when using it outside its module.
  • Avoid using uninitialized values when generating anchors.
• Fixed error loading the QtQuick.Controls module with generateQmltypes enabled. If qmlprojectexporter can't find such modules, use the --qml-mappings-dir argument to provide more information.
• Fixed compilation errors in the interface files when using C++ features from the chosen C++ standard for the project. For example, if CMAKE_CXX_STANDARD is set to 17, it should also be forwarded to qmlprojectexporter.
• Reduced the stack memory usage for blending the transformed images. The intermediate buffers are now allocated on the heap when needed.
• Fixed layer positioning when display rotation angle is set to 90 or 270.
• Wait for interrupts instead of busy looping exec() to sync with the GPU.
• qmlprojectexporter fixes:
  • Fixed the order of include paths passed to qmltocpp.
  • Include the Shapes, Timeline, StudioComponents module in the default search path.
• Fixed off by one error when allocating block size for images.
• Fixed transformation support to not ignore ItemBuffers.
• Fixes to examples and demos:
  • Fixed the watch demo (debug build) crash on STM32F769NI when built using the IAR toolchain.
  • Fixed linking errors when building the image_cache example for Renesas RH850 on AUTOSAR.
• Fixed image decoder to avoid a crash on STM when images are smaller than the input buffer.
• Fixed stack overflow with a debug build using the IAR toolchain.

New APIs

APIs for application development

• New QML Types
• New QML Properties

New QML Types

New QML Properties

QML Type Qt:

APIs for platform development

Changes in Previous Versions