- Qt 5.15
- What's New in Qt 5.11
- Qt 5.15.2 Reference Documentation

# What's New in Qt 5.11

## New Features in Qt 5.11

### Qt Core Module

- Added QIODevice::NewOnly and QIODevice::ExistingOnly `OpenMode` flags. When used with QFile, `NewOnly` instructs `open()` to (atomically) return `false` if the file to open exists. `ExistingOnly` instructs `open()` to (atomically) return `false` if the file does not exist.
- QFloat16 now has two methods for bulk conversion between `float16` and `float`, using hardware SIMD acceleration if available at runtime.
- QVarLengthArray now has rvalue reference versions of prepend and insert, and can hold movable-only datatypes such as `std::unique_ptr`.
- QVector now has rvalue reference versions of prepend and insert.
- QUuid `toString()` and `toByteArray()` now take a parameter specifying the generated format.
- Updated Unicode support in QString, QChar, and QTextBoundaryFinder to be compatible with Unicode 10.

### Qt Network Module

- ALPN (via Secure Transport) and thus HTTP/2 negotiation are now supported on iOS (starting from version 11).
- QNetworkRequest now has the `Http2DirectAttribute` to start a connection in HTTP/2 without first negotiating.

### Qt QML Module

- The compiler pipeline is rewritten. We now directly generate byte code from the AST, and store that as our intermediate representation.
- Optimized handling of JS calls, bringing large improvements especially when calling small functions.
- Newly written byte code interpreter brings significant performance improvements, at 80-90% of the JIT in Qt 5.10.
- `.qmlc` files are now fully platform-independent and store byte code instead of assembly.
- New hotspot JIT that generates optimized assembly for byte code that gets repeatedly executed.
- `CONFIG += qtquickcompiler` now also works in the open source version, by embedding the generated byte code at compile time.

### Qt Quick Module

- Expanded support for loading compressed textures in Image element. Now supports both `.ktx` and `.pkm` container file formats.

### Qt Quick Controls 2 Module

- AbstractButton
  - Promoted the autoRepeat property from Button to `AbstractButton`.
  - Added autoRepeatDelay and autoRepeatInterval properties.
  - Added `pressX` and `pressY` properties to expose the press point to QML.
- ButtonGroup
  - Added a `checkState` property. It indicates the combined check state of the entire group.
- CheckBox and CheckDelegate
  - No longer force tristate to `true` when setting `checkState` to `Qt.PartiallyChecked`. This allows presenting a partially checked state without being interactively tri-state.
  - No longer consider partially checked as checked. This fixes check state cycling for a non-tri-state checkbox so that it goes from partially checked to fully checked state.
  - Made it possible to implement `nextCheckState()` in QML.
- ScrollBar and ScrollIndicator
  - Added `minimumSize`, `visualSize`, and `visualPosition` properties.
- SpinBox
  - Added a `displayText` property to allow styles to create a light binding to display the textual value instead of having to call the `textFromValue()` JS-function.

### Qt 3D Module

- Scrub through animations with the `normalizedTime` property of QAbstractClipAnimator.
- Issue arbitrary ray casts in world space or screen space.
- Improved SIMD support.

### Qt Location Module

- New Qt.labs.location plugin containing experimental QML types.

### Qt WebEngine Module

- Updated to Chromium 65.
- Embedded DevTools without using a port and separate browser.
- Installable cookie filter.
- Quota permissions.

### QDoc Documentation Generator

- QDoc now uses libclang for parsing C/C++ code.

### Qt Designer Tool

- Added support for ID-based translations.

### Qt GUI Module

- On Windows Desktop, the accessibility support was updated and vastly improved. The implementation is now based on Microsoft UI Automation (it was formerly based on Microsoft Active Accessibility).
- The widgets themes available on Windows Desktop were updated to better support High-DPI displays, including fixes for several rendering issues, providing improved appearance and functionality.
- Linux Printing now supports more CUPS options with the advanced tab in QPrintPropertiesDialog, allowing many additional settings (amongst them arbitrary page ranges).
- Updated the Unicode bidirectional text algorithm to be compliant with Unicode 10.

### Qt Widgets Module

- Added quick text selection by mouse to QLineEdit.

### Qt Serial Bus Module

- Added J2534 Pass-Thru CAN plugin for communication between a computer and a vehicle.
- Added description, serial number and channel to QCanBusDeviceInfo, as far as supported by the various plugins.
- Introduced categorized logging to the CAN bus module which can be enabled by the "qt.canbus" and "qt.canbus.plugins.<pluginname>" filters.
- QCanBusFrame::isValid() now checks for invalid CAN FD payload lengths. E.g. 24 is a valid CAN FD payload length, but 28 is not.

### Qt Bluetooth Module

- Ported Bluetooth Low Energy Central role implementation to BlueZ's DBus LE API (minimum version to enable is BlueZ 5.42).

## New Modules

No new modules were added in this version.

## Platform Changes

- MSVC2013 support removed from the code base.
- Qt WebEngine now requires MSVC 2017 on Windows.
- QNX 6.6 no longer supported (note: QNX 7 remains fully supported).
- macOS 10.10 no longer supported.
- Improved Accessibility support on Win32 by adopting the Windows UI Automation framework.
- XCB: Support for missing 'dead keys' such as dasia and diaeresis.
- eglfs
  - Added support for framebuffer formats other than XRGB8888 (RGB565, ARGB8888).
  - Added experimental screen cloning support (by scanning out the same framebuffer on multiple displays).
  - Added support for operating with DRM render nodes (/dev/dri/renderDnn) in a headless mode transparent to applications.
  - Added a makespec for Renesas R-Car M3.
  - Added experimental backend for compositing Qt content with other hardware layers via VSP2 on Renesas devices.

## Technology Preview Modules

- Qt Remote Objects (TP3) - A module that allows you to easily share QObject interfaces (Signals/Slots/Properties) between processes or devices.
- Qt WebGL Streaming Plugin (TP2) - Stream applications to browsers over the network.

## Deprecated Modules

The following modules are part of the Qt 5.11 release, but are deprecated and considered for removal in subsequent releases of Qt:

- Qt Script
- Qt Quick Controls 1

## List of API Changes

The pages below contain a list of API changes in Qt 5.11:

- New Classes and Functions in Qt 5.11
- Obsolete Classes

## Additions to Other Qt 5 Releases

- What's New in Qt 5.10
- What's New in Qt 5.9
- What's New in Qt 5.8
- What's New in Qt 5.7
- What's New in Qt 5.6
- What's New in Qt 5.5
- What's New in Qt 5.4
- What's New in Qt 5.3
- What's New in Qt 5.2
- What's New in Qt 5.1
- What's New in Qt 5.0