无法在Android Studio中安装或导入Volley

Question

I'm trying to use the Volley library for making network requests in an Android app, but the instructions for installing/using Volley aren't working (I'm following this guide).

When I add this to my App build.gradle dependencies and sync

compile 'com.android.volley:volley:1.1.1'

Android Studio gives me this error:

Gradle sync failed: Could not find method compile() for arguments [com.android.volley:volley:1.1.1] on object of type org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler.
Consult IDE log for more details (Help | Show Log) (10s 809ms)

I tried changing compile to classname and the sync appears to work, but I still can't seem to use/import the Volley classes. Though I have no idea what I'm supposed to import because it's been left out of the guide for some reason. Android Studio doesn't seem to be aware of the dependency because it doesn't offer any option to add the imports:

Here is my build.gradle

apply plugin: 'com.android.application'

buildscript {
    repositories {
        mavenCentral()
        jcenter()
        maven {
            url "https://maven.google.com"
        }
        google()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.4'
        classpath 'com.android.volley:volley:1.1.1'
    }
}

// Allow plugins to declare Maven dependencies via build-extras.gradle.
allprojects {
    repositories {
        mavenCentral();
        jcenter()
    }
}

task wrapper(type: Wrapper) {
    gradleVersion = '4.1.0'
}

// Configuration properties. Set these via environment variables, build-extras.gradle, or gradle.properties.
// Refer to: http://www.gradle.org/docs/current/userguide/tutorial_this_and_that.html
ext {
    apply from: '../CordovaLib/cordova.gradle'
    // The value for android.compileSdkVersion.
    if (!project.hasProperty('cdvCompileSdkVersion')) {
        cdvCompileSdkVersion = null;
    }
    // The value for android.buildToolsVersion.
    if (!project.hasProperty('cdvBuildToolsVersion')) {
        cdvBuildToolsVersion = null;
    }
    // Sets the versionCode to the given value.
    if (!project.hasProperty('cdvVersionCode')) {
        cdvVersionCode = null
    }
    // Sets the minSdkVersion to the given value.
    if (!project.hasProperty('cdvMinSdkVersion')) {
        cdvMinSdkVersion = null
    }
    // Whether to build architecture-specific APKs.
    if (!project.hasProperty('cdvBuildMultipleApks')) {
        cdvBuildMultipleApks = null
    }
    // Whether to append a 0 "abi digit" to versionCode when only a single APK is build 
    if (!project.hasProperty('cdvVersionCodeForceAbiDigit')) {
        cdvVersionCodeForceAbiDigit = null
    }
    // .properties files to use for release signing.
    if (!project.hasProperty('cdvReleaseSigningPropertiesFile')) {
        cdvReleaseSigningPropertiesFile = null
    }
    // .properties files to use for debug signing.
    if (!project.hasProperty('cdvDebugSigningPropertiesFile')) {
        cdvDebugSigningPropertiesFile = null
    }
    // Set by build.js script.
    if (!project.hasProperty('cdvBuildArch')) {
        cdvBuildArch = null
    }

    // Plugin gradle extensions can append to this to have code run at the end.
    cdvPluginPostBuildExtras = []
}

// PLUGIN GRADLE EXTENSIONS START
// PLUGIN GRADLE EXTENSIONS END

def hasBuildExtras = file('build-extras.gradle').exists()
if (hasBuildExtras) {
    apply from: 'build-extras.gradle'
}

// Set property defaults after extension .gradle files.
if (ext.cdvCompileSdkVersion == null) {
    ext.cdvCompileSdkVersion = privateHelpers.getProjectTarget()
    //ext.cdvCompileSdkVersion = project.ext.defaultCompileSdkVersion
}
if (ext.cdvBuildToolsVersion == null) {
    ext.cdvBuildToolsVersion = privateHelpers.findLatestInstalledBuildTools()
    //ext.cdvBuildToolsVersion = project.ext.defaultBuildToolsVersion
}
if (ext.cdvDebugSigningPropertiesFile == null && file('../debug-signing.properties').exists()) {
    ext.cdvDebugSigningPropertiesFile = '../debug-signing.properties'
}
if (ext.cdvReleaseSigningPropertiesFile == null && file('../release-signing.properties').exists()) {
    ext.cdvReleaseSigningPropertiesFile = '../release-signing.properties'
}

// Cast to appropriate types.
ext.cdvBuildMultipleApks = cdvBuildMultipleApks == null ? false : cdvBuildMultipleApks.toBoolean();
ext.cdvVersionCodeForceAbiDigit = cdvVersionCodeForceAbiDigit == null ? false : cdvVersionCodeForceAbiDigit.toBoolean();
ext.cdvMinSdkVersion = cdvMinSdkVersion == null ? null : defaultMinSdkVersion
ext.cdvVersionCode = cdvVersionCode == null ? null : Integer.parseInt('' + cdvVersionCode)

def computeBuildTargetName(debugBuild) {
    def ret = 'assemble'
    if (cdvBuildMultipleApks && cdvBuildArch) {
        def arch = cdvBuildArch == 'arm' ? 'armv7' : cdvBuildArch
        ret += '' + arch.toUpperCase().charAt(0) + arch.substring(1);
    }
    return ret + (debugBuild ? 'Debug' : 'Release')
}

// Make cdvBuild a task that depends on the debug/arch-sepecific task.
task cdvBuildDebug
cdvBuildDebug.dependsOn {
    return computeBuildTargetName(true)
}

task cdvBuildRelease
cdvBuildRelease.dependsOn {
    return computeBuildTargetName(false)
}

task cdvPrintProps << {
    println('cdvCompileSdkVersion=' + cdvCompileSdkVersion)
    println('cdvBuildToolsVersion=' + cdvBuildToolsVersion)
    println('cdvVersionCode=' + cdvVersionCode)
    println('cdvVersionCodeForceAbiDigit=' + cdvVersionCodeForceAbiDigit)
    println('cdvMinSdkVersion=' + cdvMinSdkVersion)
    println('cdvBuildMultipleApks=' + cdvBuildMultipleApks)
    println('cdvReleaseSigningPropertiesFile=' + cdvReleaseSigningPropertiesFile)
    println('cdvDebugSigningPropertiesFile=' + cdvDebugSigningPropertiesFile)
    println('cdvBuildArch=' + cdvBuildArch)
    println('computedVersionCode=' + android.defaultConfig.versionCode)
    android.productFlavors.each { flavor ->
        println('computed' + flavor.name.capitalize() + 'VersionCode=' + flavor.versionCode)
    }
}

android {

    defaultConfig {
        versionCode cdvVersionCode ?: new BigInteger("" + privateHelpers.extractIntFromManifest("versionCode"))
        applicationId privateHelpers.extractStringFromManifest("package")

        if (cdvMinSdkVersion != null) {
            minSdkVersion cdvMinSdkVersion
        }
    }

    lintOptions {
      abortOnError false;
    }

    compileSdkVersion cdvCompileSdkVersion
    buildToolsVersion cdvBuildToolsVersion

    //This code exists for Crosswalk and other Native APIs.
    //By default, we multiply the existing version code in the Android Manifest by 10 and 
    //add a number for each architecture.  If you are not using Crosswalk or SQLite, you can
    //ignore this chunk of code, and your version codes will be respected.

    if (Boolean.valueOf(cdvBuildMultipleApks)) {
        flavorDimensions "default"

        productFlavors {
            armeabi {
                versionCode defaultConfig.versionCode*10 + 1
                ndk {
                    abiFilters = ["armeabi"]
                }
            }
            armv7 {
                versionCode defaultConfig.versionCode*10 + 2
                ndk {
                    abiFilters = ["armeabi-v7a"]
                }
            }
            arm64 {
                versionCode defaultConfig.versionCode*10 + 3
                ndk {
                    abiFilters = ["arm64-v8a"]
                }
            }
            x86 {
                versionCode defaultConfig.versionCode*10 + 4
                ndk {
                    abiFilters = ["x86"]
                }
            }
            x86_64 {
                versionCode defaultConfig.versionCode*10 + 5
                ndk {
                    abiFilters = ["x86_64"]
                }
            }
        }
    } else if (Boolean.valueOf(cdvVersionCodeForceAbiDigit)) {
        // This provides compatibility to the default logic for versionCode before cordova-android 5.2.0
        defaultConfig {
            versionCode defaultConfig.versionCode*10
        }
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    if (cdvReleaseSigningPropertiesFile) {
        signingConfigs {
            release {
                // These must be set or Gradle will complain (even if they are overridden).
                keyAlias = ""
                keyPassword = "__unset" // And these must be set to non-empty in order to have the signing step added to the task graph.
                storeFile = null
                storePassword = "__unset"
            }
        }
        buildTypes {
            release {
                signingConfig signingConfigs.release
            }
        }
        addSigningProps(cdvReleaseSigningPropertiesFile, signingConfigs.release)
    }
    if (cdvDebugSigningPropertiesFile) {
        addSigningProps(cdvDebugSigningPropertiesFile, signingConfigs.debug)
    }
}

/*
 * WARNING: Cordova Lib and platform scripts do management inside of this code here,
 * if you are adding the dependencies manually, do so outside the comments, otherwise
 * the Cordova tools will overwrite them
 */


dependencies {
    implementation fileTree(dir: 'libs', include: '*.jar')
    // SUB-PROJECT DEPENDENCIES START
    implementation(project(path: ":CordovaLib"))
    compile "com.android.support:support-v4:24.1.1+"
    // SUB-PROJECT DEPENDENCIES END
}

def promptForReleaseKeyPassword() {
    if (!cdvReleaseSigningPropertiesFile) {
        return;
    }
    if ('__unset'.equals(android.signingConfigs.release.storePassword)) {
        android.signingConfigs.release.storePassword = privateHelpers.promptForPassword('Enter key store password: ')
    }
    if ('__unset'.equals(android.signingConfigs.release.keyPassword)) {
        android.signingConfigs.release.keyPassword = privateHelpers.promptForPassword('Enter key password: ');
    }
}

gradle.taskGraph.whenReady { taskGraph ->
    taskGraph.getAllTasks().each() { task ->
      if(['validateReleaseSigning', 'validateSigningRelease', 'validateSigningArmv7Release', 'validateSigningX76Release'].contains(task.name)) {
         promptForReleaseKeyPassword()
      }
    }
}

def addSigningProps(propsFilePath, signingConfig) {
    def propsFile = file(propsFilePath)
    def props = new Properties()
    propsFile.withReader { reader ->
        props.load(reader)
    }

    def storeFile = new File(props.get('key.store') ?: privateHelpers.ensureValueExists(propsFilePath, props, 'storeFile'))
    if (!storeFile.isAbsolute()) {
        storeFile = RelativePath.parse(true, storeFile.toString()).getFile(propsFile.getParentFile())
    }
    if (!storeFile.exists()) {
        throw new FileNotFoundException('Keystore file does not exist: ' + storeFile.getAbsolutePath())
    }
    signingConfig.keyAlias = props.get('key.alias') ?: privateHelpers.ensureValueExists(propsFilePath, props, 'keyAlias')
    signingConfig.keyPassword = props.get('keyPassword', props.get('key.alias.password', signingConfig.keyPassword))
    signingConfig.storeFile = storeFile
    signingConfig.storePassword = props.get('storePassword', props.get('key.store.password', signingConfig.storePassword))
    def storeType = props.get('storeType', props.get('key.store.type', ''))
    if (!storeType) {
        def filename = storeFile.getName().toLowerCase();
        if (filename.endsWith('.p12') || filename.endsWith('.pfx')) {
            storeType = 'pkcs12'
        } else {
            storeType = signingConfig.storeType // "jks"
        }
    }
    signingConfig.storeType = storeType
}

for (def func : cdvPluginPostBuildExtras) {
    func()
}

// This can be defined within build-extras.gradle as:
//     ext.postBuildExtras = { ... code here ... }
if (hasProperty('postBuildExtras')) {
    postBuildExtras()
}

Why isn't this working? I've tried cleaning the project and restarting Android Studio.

Answer 1

Instead of putting volley dependency inside buildscript , try to include it inside

dependencies {
    implementation fileTree(dir: 'libs', include: '*.jar')
    compile 'com.android.volley:volley:1.1.1'
    // SUB-PROJECT DEPENDENCIES START
    implementation(project(path: ":CordovaLib"))
    compile "com.android.support:support-v4:24.1.1+"
    // SUB-PROJECT DEPENDENCIES END
}