要安装哪个模块来修复 Yocto 的“模块 QtQuick.Controls.Styles 未安装”错误？答案

【问题标题】：Which module to install to fix "module QtQuick.Controls.Styles is not installed" error for Yocto?要安装哪个模块来修复 Yocto 的“模块 QtQuick.Controls.Styles 未安装”错误？
【发布时间】：2018-10-15 12:08:01
【问题描述】：

我已经按照this tutorial 成功为 RPi2 构建了 Yocto 映像。我决定扩展 QML 演示并尝试一些 Qt 快速样式 (import QtQuick.Controls.Styles 1.4)。

这是图片的bb 文件

# Pulled from a mix of different images:
include recipes-core/images/rpi-basic-image.bb

# This image is a little more full featured, and includes wifi
# support, provided you have a raspberrypi3
inherit linux-raspberrypi-base

SUMMARY = "The minimal image that can run Qt5 applications"
LICENSE = "MIT"

# depend on bcm2835, which will bring in rpi-config
DEPENDS += "bcm2835-bootfiles"

MY_TOOLS = " \
    qtbase \
    qtbase-dev \
    qtbase-mkspecs \
    qtbase-plugins \
    qtbase-tools \
"

MY_PKGS = " \
    qt3d \
    qt3d-dev \
    qt3d-mkspecs \
    qtcharts \
    qtcharts-dev \
    qtcharts-mkspecs \
    qtconnectivity-dev \
    qtconnectivity-mkspecs \
    qtquickcontrols2 \
    qtquickcontrols2-dev \
    qtquickcontrols2-mkspecs \
    qtdeclarative \
    qtdeclarative-dev \
    qtdeclarative-mkspecs \
    qtgraphicaleffects \
    qtgraphicaleffects-dev \
"

MY_FEATURES = " \
    linux-firmware-bcm43430 \
    bluez5 \
    i2c-tools \
    python-smbus \
    bridge-utils \
    hostapd \
    dhcp-server \
    iptables \
    wpa-supplicant \
"

DISTRO_FEATURES_append += " bluez5 bluetooth wifi"

IMAGE_INSTALL_append = " \
    ${MY_TOOLS} \
    ${MY_PKGS} \
    ${MY_FEATURES} \
    basicquick \
"
# Qt >5.7 doesn't ship with fonts, so these need to be added explicitely
IMAGE_INSTALL_append = "\
    ttf-dejavu-sans \
    ttf-dejavu-sans-mono \
    ttf-dejavu-sans-condensed \
    ttf-dejavu-serif \
    ttf-dejavu-serif-condensed \
    ttf-dejavu-common \
"

以及演示本身的 bb 文件

SUMMARY = "Simple Qt5 Quick application"
SECTION = "examples"
LICENSE = "MIT"
LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/MIT;md5=0835ade698e0bcf8506ecda2f7b4f302"

# I want to make sure these get installed too.
DEPENDS += "qtbase qtdeclarative qtquickcontrols2"

SRCREV = "${AUTOREV}"

# GitLab own repo
SRC_URI[sha256sum] = "f2dcc13cda523e9aa9e8e1db6752b3dfaf4b531bfc9bb8e272eb3bfc5974738a"
SRC_URI = "git://git@gitlab.com:/some-repo.git;protocol=ssh"

S = "${WORKDIR}/git"

require recipes-qt/qt5/qt5.inc

do_install() {
      install -d ${D}${bindir}
      install -m 0755 BasicQuick ${D}${bindir}
}

执行时出现错误

QQmlApplicationEngine failed to load component
qrc:/main.qml:24 Type Page2 unavailable
qrc:/Page2.qml:4 module "QtQuick.Controls.Styles" is not installed

Page2 是我在main.qml 中定义和使用的项目。该演示在我的 PC（自定义构建的 Qt 5.9.1）上运行没有任何问题，但由于缺少子模块而在 RPi2 上失败。

坦率地说，我以前从未使用过这个子模块（我自定义构建的 Qt 5.9.1 已启用所有功能）并且我不确定我需要包含什么（如果 meta-qt5 甚至提供它）以便能够使用它在 Yocto 系统上。

【问题讨论】：

尝试添加 QML 模块
具体名称是什么？我试过qtqml 但bitbake 告诉我没有构建提供程序。
顺便说一句，我正在寻找 here 的模块。

标签： qt qml yocto bitbake qtquickcontrols

【解决方案1】：

问题在于 Qt Quick Controls 包的版本不匹配。

您使用的是版本 1：

import QtQuick.Controls.Styles 1.4

但构建版本 2：

MY_PKGS = " \
    ...
    qtquickcontrols2 \
    ...

您需要在图片中包含qtquickcontrols。

【讨论】：

【解决方案2】：

你需要安装qtquickcontrols-qmlplugins。

只需添加到 build/local.conf

PACKAGECONFIG_append_pn-qtbase = " accessibility"
PACKAGECONFIG_append_pn-qtquickcontrols = " accessibility"

IMAGE_INSTALL_append = " qtdeclarative-qmlplugins qtquickcontrols-qmlplugins"

这里是原始手册 https://importgeek.wordpress.com/2018/07/17/module-qtquick-controls-is-not-installed/

【讨论】：