Java Android应用程序启动时崩溃

我正试图从API获取数据并将其显示在我的应用程序上，我在youtube上遵循了本教程。但是，应用程序在启动时崩溃

我的logcat看起来像这样

2020-06-27 11:08:12.721 15553-15553/? E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.postandgetmethods, PID: 15553
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.postandgetmethods/com.example.postandgetmethods.MainActivity}: android.view.InflateException: Binary XML file line #2 in com.example.postandgetmethods:layout/activity_main: Binary XML file line #2 in com.example.postandgetmethods:layout/activity_main: Error inflating class android.support.constraint.ConstraintLayout
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3341)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3485)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2045)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:223)
        at android.app.ActivityThread.main(ActivityThread.java:7478)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:549)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941)
     Caused by: android.view.InflateException: Binary XML file line #2 in com.example.postandgetmethods:layout/activity_main: Binary XML file line #2 in com.example.postandgetmethods:layout/activity_main: Error inflating class android.support.constraint.ConstraintLayout
     Caused by: android.view.InflateException: Binary XML file line #2 in com.example.postandgetmethods:layout/activity_main: Error inflating class android.support.constraint.ConstraintLayout
     Caused by: java.lang.ClassNotFoundException: android.support.constraint.ConstraintLayout
        at java.lang.Class.classForName(Native Method)
        at java.lang.Class.forName(Class.java:454)
        at android.view.LayoutInflater.createView(LayoutInflater.java:813)
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:1004)
        at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:959)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:657)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:532)
        at android.view.LayoutInflater.inflate(LayoutInflater.java:479)
        at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:555)
        at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:161)
        at com.example.postandgetmethods.MainActivity.onCreate(MainActivity.java:28)
        at android.app.Activity.performCreate(Activity.java:7989)
        at android.app.Activity.performCreate(Activity.java:7978)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3316)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3485)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2045)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:223)
        at android.app.ActivityThread.main(ActivityThread.java:7478)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:549)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941)
2020-06-27 11:08:12.721 15553-15553/? E/AndroidRuntime: Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.constraint.ConstraintLayout" on path: DexPathList[[zip file "/data/app/~~u0jWOJVYk6PLbd0nWtsztQ==/com.example.postandgetmethods-LsaTPpzZ3pkwHDpHtScTHg==/base.apk"],nativeLibraryDirectories=[/data/app/~~u0jWOJVYk6PLbd0nWtsztQ==/com.example.postandgetmethods-LsaTPpzZ3pkwHDpHtScTHg==/lib/x86, /system/lib, /system_ext/lib, /product/lib]]
        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:207)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
            ... 26 more

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我已经完成了演示，在这个演示项目中，他们使用以下依赖项来添加约束布局

compile 'com.android.support.constraint:constraint-layout:1.0.2 

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在您的项目中，您可能正在使用androidx依赖项。检查项目中的依赖项，并将其替换为android.support.constraint.ConstraintLayout到androidx.ConstraintLayout.widget.ConstraintLayout。

这是否回答了您的问题？