Can't import androidx. Error: 'Package androidx.core.app does not exist.'

[VicDm]

I would like to integrate Android Auto compatibility in my mobile app. For this I would like to use the androidx library. However when I try to import anything from androidx I get an error.

NotificationRegistry.java:17: error: package androidx.core.app does not exist
:-1: error: ninja: build stopped: subcommand failed.

For example currently I am trying to import "import androidx.core.app.RemoteInput;" in my java class. I found a topic on this forum dated back in 2020 where it said to enableJetifier I did this, however that did not help me.

Below is my build.gradle

buildscript {
    repositories {
        google()
        mavenCentral()
    }

    dependencies {
        //noinspection AndroidGradlePluginVersion
        classpath 'com.android.tools.build:gradle:8.9.0'
    }
}

allprojects {
    repositories {
        google()
        mavenCentral()
    }
}

repositories {
    google()
    mavenCentral()
}

apply plugin: qtGradlePluginType

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar', '*.aar'])
    //noinspection GradleDependency
    implementation 'androidx.core:core:1.15.0'
}

android {
    /*******************************************************
     * The following variables:
     * - androidBuildToolsVersion,
     * - androidCompileSdkVersion
     * - qtAndroidDir - holds the path to qt android files
     *                   needed to build any Qt application
     *                   on Android.
     * - qtGradlePluginType - whether to build an app or a library
     *
     * are defined in gradle.properties file. This file is
     * updated by QtCreator and androiddeployqt tools.
     * Changing them manually might break the compilation!
     *******************************************************/

    namespace androidPackageName
    compileSdkVersion androidCompileSdkVersion
    buildToolsVersion androidBuildToolsVersion
    ndkVersion androidNdkVersion

    // Extract native libraries from the APK
    packagingOptions.jniLibs.useLegacyPackaging true

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = [qtAndroidDir + '/src', 'src', 'java']
            aidl.srcDirs = [qtAndroidDir + '/src', 'src', 'aidl']
            res.srcDirs = [qtAndroidDir + '/res', 'res']
            resources.srcDirs = ['resources']
            renderscript.srcDirs = ['src']
            assets.srcDirs = ['assets']
            jniLibs.srcDirs = ['libs']
       }
    }

    tasks.withType(JavaCompile) {
        options.incremental = true
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_17
        targetCompatibility JavaVersion.VERSION_17
    }

    lintOptions {
        abortOnError false
    }

    // Do not compress Qt binary resources file
    aaptOptions {
        noCompress 'rcc'
    }

    defaultConfig {
        resConfig "en"
        minSdkVersion qtMinSdkVersion
        targetSdkVersion qtTargetSdkVersion
        ndk.abiFilters = qtTargetAbiList.split(",")
    }
}

I then tried to manually set the minimum sdk & target sdk version, etc but this gets overriden with a new value set by Qt Creator during every build. Below is a short snippet of my gradle.properties file. the code commented out is what I manually add but then is overridden by Qt and as you see I have enabled jetifier and the use of AndroidX.

gradle.properties

android.useAndroidX=true
android.enableJetifier=true
#androidNdkVersion=29.0.13113456
androidNdkVersion=26.1.10909125
#qtMinSdkVersion=29
qtTargetAbiList=arm64-v8a
#qtTargetSdkVersion=35
qtMinSdkVersion=28
qtTargetSdkVersion=34

When I open my project in android studio using Debug APK I see that androidx exists however I can't import it in any of my java classes.

I am new to QT and would really appreciate some help. If you need any other information please do let me know. Thanks in advance !

[J.Hilk]

1.15.0 is the latest stable version, its possible its not part of your repo

I'm using implementation 'androidx.core:core:1.13.1' and classpath 'com.android.tools.build:gradle:8.6.0' and I'm using this repo, specified in the cradle-wrapper.properties:
distributionUrl=https://services.gradle.org/distributions/gradle-8.10-bin.zip

I do not use Android auto, so I don't know if these settings would help you ?

[VicDm]

This post is deleted!

[VicDm]

@J-Hilk Yes, that's what I initially had. These settings weren't working for me this is why I updated the versions thinking that maybe I need a latest version. Are you able to import " import androidx.core.app.NotificationCompat; " into any of your java classes? This is just one of the imports but can be a good example to test.

[J.Hilk]

I'm actively using:

import androidx.core.content.FileProvider;
import androidx.core.app.ShareCompat;

the the files are there for me :D

[VicDm]

@J-Hilk Oh that's interesting, may I know If you use Qt 6.8.2 or not? As that's what I am using. It would also be helpful if you could compare the below gradle.properties to yours so that I can try changing the values. android.useAndroidX=true
android.enableJetifier=true
androidBuildToolsVersion=35.0.0
androidCompileSdkVersion=android-35
androidNdkVersion=26.1.10909125
buildDir=build
qt5AndroidDir=/Users/abcd/Qt/6.8.2/android_arm64_v8a/./src/android/java
qtAndroidDir=/Users/abcd/Qt/6.8.2/android_arm64_v8a/./src/android/java
qtGradlePluginType=com.android.application
qtTargetAbiList=arm64-v8a
qtMinSdkVersion=28
qtTargetSdkVersion=34

[J.Hilk]

@VicDm
there's nothing special to it, here it is in full. I did remove commented out stuff for readability:

buildscript {
    repositories {
        google()
        mavenCentral()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:8.6.0'
    }
}

repositories {
    google()
    mavenCentral()
}

apply plugin: qtGradlePluginType

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar', '*.aar'])
    implementation 'androidx.core:core:1.13.1'
}

android {
    /*******************************************************
     * The following variables:
     * - androidBuildToolsVersion,
     * - androidCompileSdkVersion
     * - qtAndroidDir - holds the path to qt android files
     *                   needed to build any Qt application
     *                   on Android.
     * - qtGradlePluginType - whether to build an app or a library
     *
     * are defined in gradle.properties file. This file is
     * updated by QtCreator and androiddeployqt tools.
     * Changing them manually might break the compilation!
     *******************************************************/

    namespace androidPackageName
    compileSdkVersion androidCompileSdkVersion
    buildToolsVersion androidBuildToolsVersion
    ndkVersion androidNdkVersion

    // Extract native libraries from the APK
    packagingOptions.jniLibs.useLegacyPackaging true

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = [qtAndroidDir + '/src', 'src', 'java']
            aidl.srcDirs = [qtAndroidDir + '/src', 'src', 'aidl']
            res.srcDirs = [qtAndroidDir + '/res', 'res']
            resources.srcDirs = ['resources']
            renderscript.srcDirs = ['src']
            assets.srcDirs = ['assets']
            jniLibs.srcDirs = ['libs']
       }
    }

    tasks.withType(JavaCompile) {
        options.incremental = true
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    lintOptions {
        abortOnError false
    }

    // Do not compress Qt binary resources file
    aaptOptions {
        noCompress 'rcc'
    }

    defaultConfig {
        resConfig "en"
        minSdkVersion qtMinSdkVersion
        targetSdkVersion qtTargetSdkVersion
        ndk.abiFilters = qtTargetAbiList.split(",")
    }
}

I spend a lot of time the last couple of weeks trying to compile with Qt6. The the .gradle file might be a bit messy.

[VicDm]

@J-Hilk So you do use qt 6.8.2 ? and your values in gradle.properties are similar to mine? as you have shared your build.gradle file with me and not gradle.properties.

[J.Hilk]

6.8.1

# Project-wide Gradle settings.
# For more details on how to configure your build environment visit
# http://www.gradle.org/docs/current/userguide/build_environment.html
# Specifies the JVM arguments used for the daemon process.
# The setting is particularly useful for tweaking memory settings.
org.gradle.jvmargs=-Xmx2500m -XX:MaxMetaspaceSize=768m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8

# Enable building projects in parallel
org.gradle.parallel=true

# Gradle caching allows reusing the build artifacts from a previous
# build with the same inputs. However, over time, the cache size will
# grow. Uncomment the following line to enable it.
#org.gradle.caching=true
#org.gradle.configuration-cache=true

# Allow AndroidX usage
android.useAndroidX=true

[VicDm]

@J-Hilk I checked my dependencies in my project and it shows androidx.core. It's actually really difficult to pin point the issue. I tried going through my files and documentation online. I'm not sure, do I need to mention explicitly somewhere about the usage of androidx or do I need some additional statements in my AndroidManifest ?

[J.Hilk]

In my case I actually have to reference it in the AndroidManifest

<provider android:name="androidx.core.content.FileProvider" android:authorities="redacted" android:exported="false" android:grantUriPermissions="true">
            <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/filepaths"/>
        </provider>

But thats so that the file provider from the androidx library actually gets the needed permissions to function correctly.

Shouldn't matter for compilation

[VicDm]

@J-Hilk This is what I have in my AndroidManifest.

<provider android:name="androidx.core.content.FileProvider" android:authorities="${applicationId}.qtprovider" android:exported="false" android:grantUriPermissions="true">
           <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/qtprovider_paths"/>
</provider>

this is newly generated in every build.

qtprovider_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <files-path name="files_path" path="/"/>
</paths>

Is there something missing here?

[J.Hilk]

ok, maybe I should have started with this.

Do you provide QtCreator & qmake/cmake - I presume you use QtC - with your own android & gradle settings/files ? And if you think you do, how exactly ?

[VicDm]

@J-Hilk Yes I use CMake and the android & gradle settings/files are generated by QT on build.

/Users/abcd/Workspace/App/build/Android_Qt_6_8_2_Clang_arm64_v8a-Debug/android-build-LiftboyApp/build.gradle

android_bundle.cmake

if (ANDROID)
    set(LFSP_ANDROID_DIR ${CMAKE_CURRENT_SOURCE_DIR}/android)
    option(QT_ANDROID_BUILD_ALL_ABIS ON)

    set_target_properties(${LFSP_APP_BUNDLE} PROPERTIES
        QT_ANDROID_PACKAGE_SOURCE_DIR ${LFSP_ANDROID_DIR}
        RESOURCE  ${LFSP_ANDROID_DIR}/AndroidManifest.xml
        QT_ANDROID_TARGET_SDK_VERSION ${LFSP_ANDROID_TARGET_SDK}
        QT_ANDROID_VERSION_NAME ${CMAKE_PROJECT_VERSION}
        QT_ANDROID_VERSION_CODE ${LFSP_ANDROID_VERSION_CODE}
        QT_ANDROID_BUILD_ALL_ABIS ${LFSP_ANDROID_ALL_ABIS})
    message("android: ${LFSP_APP_BUNDLE} v${CMAKE_PROJECT_VERSION}, code ${LFSP_ANDROID_VERSION_CODE}, target-sdk: ${LFSP_ANDROID_TARGET_SDK}, all abis: ${LFSP_ANDROID_ALL_ABIS}")
endif()

short snippet of CMakeLists.txt

set(LFSP_BASE ${CMAKE_CURRENT_LIST_DIR}/..)
set(LFSP_ANDROID_VERSION_CODE 87)
set(LFSP_ANDROID_TARGET_SDK 34)
set(LFSP_ANDROID_JAVA_VERSION 17)
if(CMAKE_BUILD_TYPE STRLESS_EQUAL "Debug")
    set(LFSP_ANDROID_ALL_ABIS OFF)
else()
    set(LFSP_ANDROID_ALL_ABIS ON)
endif()
set(LFSP_APP_BUNDLE App CACHE STRING "" FORCE)
include(android_bundle)

[J.Hilk]

ok, my cmake experience is nearly non existent, but it seems to be fine. Mmh.

I have no idea why it doesn't work for you.

[VicDm]

@J-Hilk It all looks fine to me as well, this is why it's even more difficult to find the issue. Oh well, guess I have to spend more time on this than I had planned to. Thanks for all your help tho, I highly appreciate it! :)