突然發(fā)現(xiàn)好多安卓項(xiàng)目已經(jīng)改為了AndroidX，那么自己的項(xiàng)目也該升級一下了。下面是AndroidX的官方文檔的概述。
AndroidX概述
AndroidX是Android團(tuán)隊(duì)用于在Jetpack中開發(fā)，測試，打包，版本和發(fā)布庫的開源項(xiàng)目 。
AndroidX是對原始Android 支持庫的重大改進(jìn) 。與支持庫一樣，AndroidX與Android操作系統(tǒng)分開提供，并提供跨Android版本的向后兼容性。AndroidX通過提供功能奇偶校驗(yàn)和新庫完全取代了支持庫。此外，AndroidX還包括以下功能：
AndroidX中的所有軟件包都以字符串開頭，位于一致的命名空間中androidx。支持庫包已映射到相應(yīng)的androidx.*包中。
與支持庫不同，AndroidX軟件包是單獨(dú)維護(hù)和更新的。這些androidx包使用 從版本1.0.0開始的嚴(yán)格語義版本控制。您可以單獨(dú)更新項(xiàng)目中的AndroidX庫。
所有新的支持庫開發(fā)都將在AndroidX庫中進(jìn)行。這包括維護(hù)原始支持庫工件和引入新的Jetpack組件。
1、修改project目錄下 gradle.properties，在里面添加兩行代碼：
# 表示使用 androidx
android.useAndroidX=true
# 表示將第三方庫遷移到 androidx
android.enableJetifier=true
2、點(diǎn)擊菜單項(xiàng)中的Refactor中的Migratet to AndroidX。然后點(diǎn)擊窗口右上角的sync Now。（adnroid studio版本必須在3.3及以上）
3、按理說這樣就可以了，但是我改了之后發(fā)現(xiàn)項(xiàng)目一片報(bào)紅，上網(wǎng)搜了下發(fā)現(xiàn)需要修改引用包，都需要改為AndroidX的包，下面是我遇到的幾個(gè)錯(cuò)誤：
? ? ?a、AndroidManifest.xml中的application中的activity全部報(bào)紅，解決方法：修改activity引用的包為：
import androidx.appcompat.app.AppCompatActivity
? ? ? ? ?然后再app的build.gradle中的android中添加以下代碼：
? ? lintOptions {
? ? ? ? disable 'GoogleAppIndexingWarning'
? ? }
? ? b、剩下的還是各種包導(dǎo)入錯(cuò)誤，之前的v4、v7包全部不能用了，都需要改。
? ? c、布局文件也一定要改，比如ViewPager由android.support.v4.view.ViewPager改為了androidx.viewpager.widget.ViewPager；CardView由android.support.v7.widget.CardView改為了androidx.cardview.widget.CardView；RecycleView由android.support.v7.widget.RecycleView改為了com.scwang.smartrefresh.layout.SmartRefreshLayout；FloatingActionButton也改為了com.google.android.material.floatingactionbutton.FloatingActionButton。
這只是一部分，下面的是官網(wǎng)上的介紹：
Old build artifactAndroidX build artifact
android.arch.core:commonandroidx.arch.core:core-common:2.0.0-rc01
android.arch.core:coreandroidx.arch.core:core:2.0.0-rc01
android.arch.core:core-testingandroidx.arch.core:core-testing:2.0.0-rc01
android.arch.core:runtimeandroidx.arch.core:core-runtime:2.0.0-rc01
android.arch.lifecycle:commonandroidx.lifecycle:lifecycle-common:2.0.0-rc01
android.arch.lifecycle:common-java8androidx.lifecycle:lifecycle-common-java8:2.0.0-rc01
android.arch.lifecycle:compilerandroidx.lifecycle:lifecycle-compiler:2.0.0-rc01
android.arch.lifecycle:extensionsandroidx.lifecycle:lifecycle-extensions:2.0.0-rc01
android.arch.lifecycle:livedataandroidx.lifecycle:lifecycle-livedata:2.0.0-rc01
android.arch.lifecycle:livedata-coreandroidx.lifecycle:lifecycle-livedata-core:2.0.0-rc01
android.arch.lifecycle:reactivestreamsandroidx.lifecycle:lifecycle-reactivestreams:2.0.0-rc01
android.arch.lifecycle:runtimeandroidx.lifecycle:lifecycle-runtime:2.0.0-rc01
android.arch.lifecycle:viewmodelandroidx.lifecycle:lifecycle-viewmodel:2.0.0-rc01
android.arch.paging:commonandroidx.paging:paging-common:2.0.0-rc01
android.arch.paging:runtimeandroidx.paging:paging-runtime:2.0.0-rc01
android.arch.paging:rxjava2androidx.paging:paging-rxjava2:2.0.0-rc01
android.arch.persistence.room:commonandroidx.room:room-common:2.0.0-rc01
android.arch.persistence.room:compilerandroidx.room:room-compiler:2.0.0-rc01
android.arch.persistence.room:guavaandroidx.room:room-guava:2.0.0-rc01
android.arch.persistence.room:migrationandroidx.room:room-migration:2.0.0-rc01
android.arch.persistence.room:runtimeandroidx.room:room-runtime:2.0.0-rc01
android.arch.persistence.room:rxjava2androidx.room:room-rxjava2:2.0.0-rc01
android.arch.persistence.room:testingandroidx.room:room-testing:2.0.0-rc01
android.arch.persistence:dbandroidx.sqlite:sqlite:2.0.0-rc01
android.arch.persistence:db-frameworkandroidx.sqlite:sqlite-framework:2.0.0-rc01
com.android.support.constraint:constraint-layoutandroidx.constraintlayout:constraintlayout:1.1.2
com.android.support.constraint:constraint-layout-solverandroidx.constraintlayout:constraintlayout-solver:1.1.2
com.android.support.test.espresso.idling:idling-concurrentandroidx.test.espresso.idling:idling-concurrent:3.1.0
com.android.support.test.espresso.idling:idling-netandroidx.test.espresso.idling:idling-net:3.1.0
com.android.support.test.espresso:espresso-accessibilityandroidx.test.espresso:espresso-accessibility:3.1.0
com.android.support.test.espresso:espresso-contribandroidx.test.espresso:espresso-contrib:3.1.0
com.android.support.test.espresso:espresso-coreandroidx.test.espresso:espresso-core:3.1.0
com.android.support.test.espresso:espresso-idling-resourceandroidx.test.espresso:espresso-idling-resource:3.1.0
com.android.support.test.espresso:espresso-intentsandroidx.test.espresso:espresso-intents:3.1.0
com.android.support.test.espresso:espresso-remoteandroidx.test.espresso:espresso-remote:3.1.0
com.android.support.test.espresso:espresso-webandroidx.test.espresso:espresso-web:3.1.0
com.android.support.test.janktesthelper:janktesthelperandroidx.test.jank:janktesthelper:1.0.1
com.android.support.test.services:test-servicesandroidx.test:test-services:1.1.0
com.android.support.test.uiautomator:uiautomatorandroidx.test.uiautomator:uiautomator:2.2.0
com.android.support.test:monitorandroidx.test:monitor:1.1.0
com.android.support.test:orchestratorandroidx.test:orchestrator:1.1.0
com.android.support.test:rulesandroidx.test:rules:1.1.0
com.android.support.test:runnerandroidx.test:runner:1.1.0
com.android.support:animated-vector-drawableandroidx.vectordrawable:vectordrawable-animated:1.0.0
com.android.support:appcompat-v7androidx.appcompat:appcompat:1.0.0
com.android.support:asynclayoutinflaterandroidx.asynclayoutinflater:asynclayoutinflater:1.0.0
com.android.support:carandroidx.car:car:1.0.0-alpha5
com.android.support:cardview-v7androidx.cardview:cardview:1.0.0
com.android.support:collectionsandroidx.collection:collection:1.0.0
com.android.support:coordinatorlayoutandroidx.coordinatorlayout:coordinatorlayout:1.0.0
com.android.support:cursoradapterandroidx.cursoradapter:cursoradapter:1.0.0
com.android.support:customtabsandroidx.browser:browser:1.0.0
com.android.support:customviewandroidx.customview:customview:1.0.0
com.android.support:designcom.google.android.material:material:1.0.0-rc01
com.android.support:documentfileandroidx.documentfile:documentfile:1.0.0
com.android.support:drawerlayoutandroidx.drawerlayout:drawerlayout:1.0.0
com.android.support:exifinterfaceandroidx.exifinterface:exifinterface:1.0.0
com.android.support:gridlayout-v7androidx.gridlayout:gridlayout:1.0.0
com.android.support:heifwriterandroidx.heifwriter:heifwriter:1.0.0
com.android.support:interpolatorandroidx.interpolator:interpolator:1.0.0
com.android.support:leanback-v17androidx.leanback:leanback:1.0.0
com.android.support:loaderandroidx.loader:loader:1.0.0
com.android.support:localbroadcastmanagerandroidx.localbroadcastmanager:localbroadcastmanager:1.0.0
com.android.support:media2androidx.media2:media2:1.0.0-alpha03
com.android.support:media2-exoplayerandroidx.media2:media2-exoplayer:1.0.0-alpha01
com.android.support:mediarouter-v7androidx.mediarouter:mediarouter:1.0.0
com.android.support:multidexandroidx.multidex:multidex:2.0.0
com.android.support:multidex-instrumentationandroidx.multidex:multidex-instrumentation:2.0.0
com.android.support:palette-v7androidx.palette:palette:1.0.0
com.android.support:percentandroidx.percentlayout:percentlayout:1.0.0
com.android.support:preference-leanback-v17androidx.leanback:leanback-preference:1.0.0
com.android.support:preference-v14androidx.legacy:legacy-preference-v14:1.0.0
com.android.support:preference-v7androidx.preference:preference:1.0.0
com.android.support:printandroidx.print:print:1.0.0
com.android.support:recommendationandroidx.recommendation:recommendation:1.0.0
com.android.support:recyclerview-selectionandroidx.recyclerview:recyclerview-selection:1.0.0
com.android.support:recyclerview-v7androidx.recyclerview:recyclerview:1.0.0
com.android.support:slices-buildersandroidx.slice:slice-builders:1.0.0
com.android.support:slices-coreandroidx.slice:slice-core:1.0.0
com.android.support:slices-viewandroidx.slice:slice-view:1.0.0
com.android.support:slidingpanelayoutandroidx.slidingpanelayout:slidingpanelayout:1.0.0
com.android.support:support-annotationsandroidx.annotation:annotation:1.0.0
com.android.support:support-compatandroidx.core:core:1.0.0
com.android.support:support-contentandroidx.contentpager:contentpager:1.0.0
com.android.support:support-core-uiandroidx.legacy:legacy-support-core-ui:1.0.0
com.android.support:support-core-utilsandroidx.legacy:legacy-support-core-utils:1.0.0
com.android.support:support-dynamic-animationandroidx.dynamicanimation:dynamicanimation:1.0.0
com.android.support:support-emojiandroidx.emoji:emoji:1.0.0
com.android.support:support-emoji-appcompatandroidx.emoji:emoji-appcompat:1.0.0
com.android.support:support-emoji-bundledandroidx.emoji:emoji-bundled:1.0.0
com.android.support:support-fragmentandroidx.fragment:fragment:1.0.0
com.android.support:support-media-compatandroidx.media:media:1.0.0
com.android.support:support-tv-providerandroidx.tvprovider:tvprovider:1.0.0
com.android.support:support-v13androidx.legacy:legacy-support-v13:1.0.0
com.android.support:support-v4androidx.legacy:legacy-support-v4:1.0.0
com.android.support:support-vector-drawableandroidx.vectordrawable:vectordrawable:1.0.0
com.android.support:swiperefreshlayoutandroidx.swiperefreshlayout:swiperefreshlayout:1.0.0
com.android.support:textclassifierandroidx.textclassifier:textclassifier:1.0.0
com.android.support:transitionandroidx.transition:transition:1.0.0
com.android.support:versionedparcelableandroidx.versionedparcelable:versionedparcelable:1.0.0
com.android.support:viewpagerandroidx.viewpager:viewpager:1.0.0
com.android.support:wearandroidx.wear:wear:1.0.0
com.android.support:webkitandroidx.webkit:webkit:1.0.0
