// Copyright (C) 2023 The Qt Company Ltd. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only /*! \page android-platform-notes.html \title Android Platform Notes \ingroup android-platform-extra-topics \previouspage Supporting Google Emoji Font Policy \nextpage Android GNU C++ Run-time Licensing \brief Information particular to building and running Qt applications on Android. This page contains information particular to building and running Qt applications on Android. See \l{android_support}{Supported Android Versions} for what Android versions and API levels are supported. \section1 Plugins and Imports Special Considerations If an application uses plugins that depend on other modules, these modules must be listed in the application's dependencies. For more information, see \l{Dependencies Detection}. \section2 Qt GUI Dependency Given that Android apps typically include GUI elements, the Qt for Android plugin is built mainly to provide a GUI, so it implements the various QPA abstractions. As a result, deploying a Qt for Android app is expected to involve a dependency on \l [QtGui]{Qt GUI}. Moreover, it's worth noting that Qt Creator only supports Gradle builds and deployments, meaning that command line or shell executions are not supported out of the box. \section1 OpenGL Special Considerations Modern devices often support OpenGL ES 3.0 or 3.1 in addition to 2.0. To get a suitable OpenGL context, set the requested version via \l{QSurfaceFormat::setVersion()}. \note Using OpenGL ES 3.x features will result in the application breaking on older devices that only support 2.0. \section1 Known Issues \section2 Qt Creator Debugging Issues See \l {\QC: Known Issues#Debugging Issues}{Qt Creator Debugging Issues on Android} for more information. \section2 Predictive Text Due to a bug on some devices, when you turn off predictive text with \c{ImhNoPredictiveText}, this property is ignored and predictive text is still enabled. To work around this, set the \c{QT_ANDROID_ENABLE_WORKAROUND_TO_DISABLE_PREDICTIVE_TEXT} environment variable to \c 1. However, one side effect is that this environment variable can cause a problem with other keyboards such as Gboard. If you use a language like Japanese, with Gboard, only a QWERTY keyboard is displayed. This environment variable is queried each time the keyboard is displayed, so it's possible to toggle the workaround on and off, as necessary. \section2 Text Glyph Caching Because of a bug in some OpenGL drivers, the mechanism used by Qt to cache text glyphs does not work as expected on all Android devices, causing text to appear scrambled. To remedy this, a workaround is in place, but it can increase memory consumption and can also affect text rendering performance. The workaround is now used by default on all devices. You can disable the workaround by setting the \c QT_ANDROID_DISABLE_GLYPH_CACHE_WORKAROUND environment variable to \e 1 or \e true. However, you should do so only after verifying that text appears correctly on all targeted devices. \section1 Limitations Some of the Qt modules or tools might have features that are not supported on Android or have limitations. See a specific module's \l{All Modules}{documentation} for any platform limitations. */