Example cmake for windows including auto copy dll

CMakeLists.txt

# _______  __   __  _______  ______   _______  _______  _______  ______  #
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#|   _   ||  | |  ||_     _||  _    ||  |_|  ||_     _||    ___||  _    |#
#|  | |  ||  |_|  |  |   |  | | |   ||       |  |   |  |   |___ | | |   |#
#|  |_|  ||       |  |   |  | |_|   ||       |  |   |  |    ___|| |_|   |#
#|       ||       |  |   |  |       ||   _   |  |   |  |   |___ |       |#
#|_______||_______|  |___|  |______| |__| |__|  |___|  |_______||______| #
#                                                                        #
#  Modern CMake practices and importing the QT scripts by adding it to   #
#    your module path makes things a lot better than it used to be       #


cmake_minimum_required(VERSION 2.8.11)

project(testproject)

set(CMAKE_PREFIX_PATH "C:/Qt/5.3/msvc2013_64/lib/cmake")
set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOMOC ON)

# Find the QtWidgets library
find_package(Qt5Widgets REQUIRED)
find_package(Qt5Core REQUIRED)
find_package(Qt5Gui REQUIRED)

QT5_WRAP_UI(UI_HEADERS mainwindow.ui)
INCLUDE_DIRECTORIES( ${CMAKE_CURRENT_BINARY_DIR} )

# Tell CMake to create the helloworld executable
add_executable(helloworld main.cpp mainwindow.cpp ${UI_HEADERS})
target_link_libraries(helloworld Qt5::Widgets)

add_custom_target(Qt5CopyBinaries
  # todo: check if debug and release folder exist
  # debug version
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/libEGLd.dll          ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/libGLESv2d.dll       ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Cored.dll         ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Guid.dll          ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Declaratived.dll  ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Networkd.dll      ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5OpenGLd.dll       ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Scriptd.dll       ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Sqld.dll          ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Widgetsd.dll      ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Xmld.dll          ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5XmlPatternsd.dll  ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/icuin52.dll          ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/icuuc52.dll          ${CMAKE_BINARY_DIR}/Debug
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/icudt52.dll          ${CMAKE_BINARY_DIR}/Debug
  
  # release version
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/libEGL.dll           ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/libGLESv2.dll        ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Core.dll          ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Gui.dll           ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Declarative.dll   ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Network.dll       ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5OpenGL.dll        ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Script.dll        ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Sql.dll           ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Widgets.dll       ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5Xml.dll           ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/Qt5XmlPatterns.dll   ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/icuin52.dll          ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/icuuc52.dll          ${CMAKE_BINARY_DIR}/Release
  COMMAND ${CMAKE_COMMAND} -E copy ${Qt5Core_DIR}/../../../bin/icudt52.dll          ${CMAKE_BINARY_DIR}/Release

  # Output Message
  COMMENT "Copying Qt binaries from '${Qt5Core_DIR}/../../bin/' to '${CMAKE_BINARY_DIR}'" VERBATIM
)

add_dependencies(helloworld Qt5CopyBinaries)

@aaichert , I don't know if this qualifies as 'elegant' for you, but I found this code that works for me. I put it in a macro that I use for my apps.

This could be simplified quite a bit with

COMMAND ${CMAKE_COMMAND} -E copy_if_different
    $<TARGET_FILE:Qt5::Core>
    $<TARGET_FILE:Qt5::Widgets>
    ... etc ... 

instead

How can I link opencv dll like this?

Beware that qml-related dependencies aren't covered by this script, and the app will fail to run, unless you use windeployqt.exe to copy all necessary modules.