CMake: qmake: Fix chapter6-plugins example to build in more configs

Before this change, I tested the following configurations / scenarios

 (1) shared Qt + qmake + macOS bundle -> works
 (2) shared Qt + CMake + macOS bundle -> broken
 (3) static Qt + qmake + macOS bundle -> broken
 (4) static Qt + CMake + macOS bundle -> works

 (2) was broken because the shared qml plugin is not located in the
 expected location (see below)
 (3) was broken because qmake needs a lot of error-prone boilerplate
 to ensure static qml plugin building and linking works.

The change fixes the example to build and run successfully in case
(2).

Tested the following scenarios on macOS with the change

  shared Qt + qmake + macOS bundle -> works
  shared Qt + CMake + macOS bundle -> works
  shared Qt + qmake + no bundle    -> works
  shared Qt + CMake + no bundle    -> works
  static Qt + qmake                -> still broken
  static Qt + CMake                -> works

To make shared qml plugins be found in a macOS bundle, we need to copy
the qmldir and plugin under the bundle's PlugIns subfolder, because
the application adds that as the expected qml import path for macOS.
This basically mimics what the qmake project does with
QMAKE_BUNDLE_DATA.

The change also cleans up the CMake projects a bit so they don't link
PUBLIC-ly against dependencies, install the plugin under a more
sensible location and don't needlessly setup package finding and other
boilerplate that's done in the parent project.

The change also cleans up the qmake projects to adjust to not pollute
the macos bundle dir with static plugin files.

Amends 9e1d2a0eb15487f8f2acb4d91b281568897fb4e1

Pick-to: 6.2
Change-Id: I45bb699a67adf598587350a03f778291fad3f850
Reviewed-by: Craig Scott <craig.scott@qt.io>
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

3 files changed, 28 insertions, 30 deletions

diff --git a/examples/qml/tutorials/extending-qml/chapter6-plugins/CMakeLists.txt b/examples/qml/tutorials/extending-qml/chapter6-plugins/CMakeLists.txt
index cf3d218c57..dc0b20dc21 100644
--- a/examples/qml/tutorials/extending-qml/chapter6-plugins/CMakeLists.txt
+++ b/examples/qml/tutorials/extending-qml/chapter6-plugins/CMakeLists.txt
@@ -25,7 +25,7 @@ set_target_properties(chapter6-plugins PROPERTIES
     WIN32_EXECUTABLE TRUE
     MACOSX_BUNDLE TRUE
 )
-target_link_libraries(chapter6-plugins PUBLIC
+target_link_libraries(chapter6-plugins PRIVATE
     Qt::Qml
     Qt::Quick
 )
diff --git a/examples/qml/tutorials/extending-qml/chapter6-plugins/Charts/CMakeLists.txt b/examples/qml/tutorials/extending-qml/chapter6-plugins/Charts/CMakeLists.txt
index 15f6dcc2c2..28efcaace8 100644
--- a/examples/qml/tutorials/extending-qml/chapter6-plugins/Charts/CMakeLists.txt
+++ b/examples/qml/tutorials/extending-qml/chapter6-plugins/Charts/CMakeLists.txt
@@ -1,25 +1,3 @@
-# Generated from import.pro.
-
-cmake_minimum_required(VERSION 3.16)
-project(chartsplugin LANGUAGES CXX)
-
-set(CMAKE_INCLUDE_CURRENT_DIR ON)
-
-set(CMAKE_AUTOMOC ON)
-set(CMAKE_AUTORCC ON)
-set(CMAKE_AUTOUIC ON)
-
-if(NOT DEFINED INSTALL_EXAMPLESDIR)
-  set(INSTALL_EXAMPLESDIR "examples")
-endif()
-
-set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/qml/tutorials/extending-qml/chapter6-plugins/Charts")
-
-find_package(Qt6 COMPONENTS Core)
-find_package(Qt6 COMPONENTS Gui)
-find_package(Qt6 COMPONENTS Qml)
-find_package(Qt6 COMPONENTS Quick)
-
 qt6_add_qml_module(chartsplugin
     VERSION 1.0
     URI "Charts"
@@ -30,17 +8,37 @@ target_sources(chartsplugin PRIVATE
     piechart.cpp piechart.h
     pieslice.cpp pieslice.h
 )
-set_target_properties(chartsplugin PROPERTIES
-    WIN32_EXECUTABLE TRUE
-    MACOSX_BUNDLE TRUE
-)
-target_link_libraries(chartsplugin PUBLIC
+
+target_link_libraries(chartsplugin PRIVATE
     Qt::Core
     Qt::Gui
     Qt::Qml
     Qt::Quick
 )
 
+if(QT6_IS_SHARED_LIBS_BUILD AND APPLE)
+    get_target_property(is_bundle chapter6-plugins MACOSX_BUNDLE)
+    if(is_bundle)
+        # The application's main.cpp adds an explicit QML import path to look for qml modules under
+        # a PlugIns subdirectory in a macOS bundle.
+        # Copy the qmldir and shared library qml plugin.
+
+        set(charts_dir "$<TARGET_FILE_DIR:chartsplugin>")
+        set(chars_qmldir_file "${charts_dir}/qmldir")
+        set(app_dir "$<TARGET_FILE_DIR:chapter6-plugins>")
+        set(bundle_charts_dir "${app_dir}/../PlugIns/Charts")
+
+        add_custom_command(TARGET chartsplugin POST_BUILD
+            COMMAND ${CMAKE_COMMAND} -E make_directory ${bundle_charts_dir}
+            COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                    $<TARGET_FILE:chartsplugin> ${bundle_charts_dir}
+            COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                    ${chars_qmldir_file} ${bundle_charts_dir}
+        )
+    endif()
+endif()
+
+set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLEDIR}/Charts")
 install(TARGETS chartsplugin
     RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
     BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
diff --git a/examples/qml/tutorials/extending-qml/chapter6-plugins/app.pro b/examples/qml/tutorials/extending-qml/chapter6-plugins/app.pro
index b340981e42..8f53075a7d 100644
--- a/examples/qml/tutorials/extending-qml/chapter6-plugins/app.pro
+++ b/examples/qml/tutorials/extending-qml/chapter6-plugins/app.pro
@@ -3,9 +3,9 @@ QT += qml quick
 
 # Ensure that the application will see the import path for the Charts module:
 #   * On Windows, do not build into a debug/release subdirectory.
-#   * On OS X, add the plugin files into the bundle.
+#   * On macOS, add the plugin files into the bundle, only in a shared build though
 win32: DESTDIR = ./
-osx {
+macos:!qtConfig(static) {
     charts.files = $$OUT_PWD/Charts
     charts.path = Contents/PlugIns
     QMAKE_BUNDLE_DATA += charts