cmake代码install(TARGETS mylib mylib_shared ARCHIVE DESTINATION lib LIBRARY DESTINATION lib RUNTIME DESTINATION bin INCLUDES DESTINATION include EXPORT MyLibTargets) 在执行时提醒 export Export set "MyLibTargets" not found.

这个错误提示是因为在执行 `install` 命令时，指定了一个名为 `MyLibTargets` 的导出配置，但是在之前的代码中并没有定义该导出配置。

解决这个问题，需要在 CMakeLists.txt 文件中添加一个 `export` 命令，用于定义 `MyLibTargets` 导出配置。例如：

# 定义导出配置
export(TARGETS mylib mylib_shared FILE MyLibTargets.cmake)

# 安装配置文件和导出配置
install(TARGETS mylib mylib_shared
        ARCHIVE DESTINATION lib
        LIBRARY DESTINATION lib
        RUNTIME DESTINATION bin
        INCLUDES DESTINATION include
        EXPORT MyLibTargets)

install(EXPORT MyLibTargets
        FILE MyLibTargets.cmake
        DESTINATION lib/cmake/MyLib)

这样，就会在安装时生成一个名为 `MyLibTargets.cmake` 的导出配置文件，并将其安装到 `lib/cmake/MyLib` 目录下。之后，在使用该库时，可以通过 `find_package(MyLib)` 命令加载导出配置文件，从而使用库。

相关问题

cmake中install(TARGETS mylib mylib_shared EXPORT MyLibTargets ARCHIVE DESTINATION lib LIBRARY DESTINATION lib RUNTIME DESTINATION bin)如何指定MyLibTargets中库的搜索路径

"
android:layout_below="@id/description_text_view"
android:layout_toRightOf="@id/image_view"
android:layout_marginLeft="8dp"
android:textSize="12sp"
android:textColor="@color/colorAccent"/>
</RelativeLayout>
``你可以在使用`install()`函数中指定`EXPORT`选项时，通过`NAMESPACE`子选项来为导出`

创建 NewsItem 类，它包含新闻的标题、描述、URL、图片 URL 和发布日期。

NewsItem.java：

的目标指定一个命名空间，然后使用`install(EXPORT)`函数导出目标时，指定````java
public class NewsItem {

private String title;
private String description;
private String url;
private String imageUrl;
DESTINATION`选项来指定导出文件的输出路径。在使用导出文件的项目中，可以使用`find_package private String publishedAt;

public NewsItem(String title, String description, String url, String imageUrl, String publishedAt) {
this.title = title;
this.description = description;
this.url = url;
this.imageUrl = imageUrl;
this.publishedAt =()`函数并指定`<MyLibName>_DIR`变量来指定导出文件所在的路径。下面是一个 publishedAt;
}

public String getTitle() {
return title;
}

public String getDescription() {
return description;
示例：

在`CMakeLists.txt`文件中：

# 导出目标
install(TARGETS mylib }

    public String getUrl() {
        return url;
    }

    public String getImageUrl() {
        return imageUrl;
    }

    public mylib_shared
        EXPORT MyLibTargets
        ARCHIVE DESTINATION lib
        LIBRARY DESTINATION lib
        RUNTIME DESTINATION String getPublishedAt() {
        return publishedAt;
    }
}

创建 NewsDetailActivity 类，它显示单个新闻 bin)

# 指定导出文件输出路径
install(EXPORT MyLibTargets
NAMESPACE MyLib::
DESTINATION lib/c的详细信息，包括标题和 URL。

NewsDetailActivity.java：

public class NewsDetailActivity extends AppCompatActivity {

    private WebView webView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_news_detailmake/MyLib)

# 在使用导出文件的项目中，通过 find_package() 函数来查找库
find_package(MyLib);

        String title = getIntent().getStringExtra("title");
        String url = getIntent().getStringExtra("url");

        getSupportActionBar().setTitle(title);
        REQUIRED)
target_link_libraries(myapp MyLib::mylib)

在导出文件 `MyLibTargets.cmake` 中：

getSupportActionBar().setDisplayHomeAsUpEnabled(true);

webView = findViewById(R.id.web_view);
webView.setWebViewClient(new WebViewClient());
webView.loadUrl```cmake
# 设置导出文件版本号
include(CMakePackageConfigHelpers)
write_basic_package_version_file("${CMAKE_CURRENT_BINARY(url);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id_DIR}/MyLibConfigVersion.cmake"
VERSION ${MyLib_VERSION}
COMPATIBILITY SameMajorVersion)

# 将目标.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}

activity_news_detail放入命名空间
export(EXPORT MyLibTargets
       NAMESPACE MyLib::
       FILE "${CMAKE_CURRENT_BINARY_DIR}/.xml：

<WebView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/web_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

最后，创建一个MyLibTargets.cmake")

# 生成配置文件
configure_package_config_file("${CMAKE_CURRENT_SOURCE_DIR}/MyLibConfig.cmake.in Service 类，它显示一个定期的通知，提醒用户查看最新的新闻。

NewsNotificationService.java：

"
                              "${CMAKE_CURRENT_BINARY_DIR}/MyLibConfig.cmake"
                              INSTALL_DESTINATION lib/cmake/MyLib)

# 安```java
public class NewsNotificationService extends Service {

    private static final int NOTIFICATION_ID = 1;
    private static final String装配置文件
install(FILES "${CMAKE_CURRENT_BINARY_DIR}/MyLibConfig.cmake"
              "${CMAKE_CURRENT_BINARY_DIR}/My CHANNEL_ID = "news_notification_channel";
    private static final String CHANNEL_NAME = "News Notification Channel";
    private static final String CHANNEL_DESCRIPTIONLibConfigVersion.cmake"
              DESTINATION lib/cmake/MyLib)

在配置文件 `MyLibConfig.cmake.in` = "Shows news notifications to the user";

private Handler handler = new Handler();
private Runnable runnable = new Runnable() {
@ 中：

# 指定库的搜索路径
set(MyLib_DIR @CMAKE_INSTALL_PREFIX@/lib/cmake/Override
        public void run() {
            showNotification();
            handler.postDelayed(this, 60 * 60 * 1000); // repeat every hour
        }
    };

    @Override
    public int onStartCommand(Intent intent, int flags, int startId)MyLib)

# 通过 find_package() 函数查找库
find_package(MyLib REQUIRED)

# 将库的头文件路径添加到 {
        createNotificationChannel();
        handler.postDelayed(runnable, 60 * 60 * 1000); // start after 1 hour include 目录中
include_directories(${MyLib_INCLUDE_DIRS})

这样，在使用 `find_package(MyLib)` 函数时，
return START_STICKY;
}

@Override
public IBinder onBind(Intent intent) {
return null;
就会自动查找到 `MyLibTargets.cmake` 文件，并将 `MyLib` 目标添加到命名空间 }

@Override
public void onDestroy() {
super.onDestroy();
handler.removeCallbacks(runnable);
}

private void createNotificationChannel() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationChannel channel = new NotificationChannel(CHANNEL `MyLib::` 中。在使用 `target_link_libraries(myapp MyLib::mylib)` 命令时，就可以通过_ID, CHANNEL_NAME,
NotificationManager.IMPORTANCE_DEFAULT);
channel.setDescription(CHANNEL_DESCRIPTION);

NotificationManager notificationManager = getSystemService(NotificationManager.class);
notificationManager.createNotificationChannel(channel);
}
}

private void showNotification() {
Intent intent = new Intent命名空间 `MyLib::` 来引用 `mylib` 目标，并且不需要手动添加库的搜索路径。

代码install(TARGETS mylib mylib_shared EXPORT MyLibConfig ARCHIVE DESTINATION lib LIBRARY DESTINATION lib RUNTIME DESTINATION bin INCLUDES DESTINATION include) install(FILES include/header.h DESTINATION include)，如何在导出的MyLibConfig添加变量设置，即set(MyLib_VERSION @MyLib_VERSION@) set(MyLib_INCLUDE_DIRS "@CMAKE_INSTALL_PREFIX@/include") set(MyLib_LIBRARIES "@CMAKE_INSTALL_PREFIX@/lib/libmylib.a") set(MyLib_LIBRARIES_SHARED "@CMAKE_INSTALL_PREFIX@/lib/libmylib_shared.so")中

你可以将这些变量设置添加到MyLibConfig.cmake.in文件中，该文件应该位于你的项目根目录下的cmake文件夹中。MyLibConfig.cmake.in文件应该类似于以下内容：

# check if the package has been loaded already
if(NOT TARGET MyLib::mylib)
    include("${CMAKE_CURRENT_LIST_DIR}/MyLibTargets.cmake")
endif()

# set version and include directories variables
set(MyLib_VERSION @MyLib_VERSION@)
set(MyLib_INCLUDE_DIRS "@CMAKE_INSTALL_PREFIX@/include")

# set library variables
set(MyLib_LIBRARIES "@CMAKE_INSTALL_PREFIX@/lib/libmylib.a")
set(MyLib_LIBRARIES_SHARED "@CMAKE_INSTALL_PREFIX@/lib/libmylib_shared.so")

当你运行`install(EXPORT MyLibConfig ...)`命令时，CMake将自动将这些变量设置添加到MyLibConfig.cmake文件中。请记住，你需要将MyLibConfig.cmake.in文件名用MyLibConfig.cmake替换，以便CMake能够正确加载它。