Android Studio按钮跳转新Activity崩溃问题求助

作为Android Studio新手，参考网上代码实现按钮跳转自定义的第二个Activity，但点击模拟器中的按钮时应用崩溃，期望按钮能打开创建的MainActivity2，相关代码及崩溃日志如下：

MainActivity代码（Kotlin） #

package com.example.plaques

import android.content.Intent
import android.os.Bundle
import android.view.View
import androidx.activity.ComponentActivity

class MainActivity : ComponentActivity() {

    // 注意：Kotlin不需要@Override注解，此注解会导致编译错误，需删除
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.application1)
    }

    fun ouvrir(view: View) {
        val intent = Intent(this, MainActivity2::class.java )
        startActivity(intent)
    }
}

布局文件（application1.xml） #

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <androidx.constraintlayout.widget.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="open next activity"
            android:onClick="ouvrir"
            tools:ignore="MissingConstraints,UsingOnClickInXml" />

    </androidx.constraintlayout.widget.ConstraintLayout>
</LinearLayout>

崩溃日志 #

--------- beginning of crash
2022-12-01 14:31:10.752 2297-2297/com.example.plaques E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.plaques, PID: 2297
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.plaques/com.example.plaques.MainActivity2}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3676)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3813)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:101)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2308)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loopOnce(Looper.java:201)
        at android.os.Looper.loop(Looper.java:288)
        at android.app.ActivityThread.main(ActivityThread.java:7898)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)
     Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
        at androidx.appcompat.app.AppCompatDelegateImpl.createSubDecor(AppCompatDelegateImpl.java:852)
        at androidx.appcompat.app.AppCompatDelegateImpl.ensureSubDecor(AppCompatDelegateImpl.java:815)
        at androidx.appcompat.app.AppCompatDelegateImpl.initWindowDecorActionBar(AppCompatDelegateImpl.java:556)
        at androidx.appcompat.app.AppCompatDelegateImpl.getSupportActionBar(AppCompatDelegateImpl.java:543)
        at androidx.appcompat.app.AppCompatDelegateImpl.invalidateOptionsMenu(AppCompatDelegateImpl.java:1226)
        at androidx.appcompat.app.AppCompatActivity.invalidateOptionsMenu(AppCompatActivity.java:314)
        at androidx.activity.ComponentActivity.invalidateMenu(ComponentActivity.java:553)
        at androidx.activity.ComponentActivity$$ExternalSyntheticLambda0.run(Unknown Source:2)
        at androidx.core.view.MenuHostHelper.addMenuProvider(MenuHostHelper.java:116)
        at androidx.activity.ComponentActivity.addMenuProvider(ComponentActivity.java:531)
        at androidx.fragment.app.FragmentActivity$HostCallbacks.addMenuProvider(FragmentActivity.java:736)
        at androidx.fragment.app.FragmentManager.attachController(FragmentManager.java:2793)
        at androidx.fragment.app.FragmentController.attachHost(FragmentController.java:117)
        at androidx.fragment.app.FragmentActivity.lambda$init$3$androidx-fragment-app-FragmentActivity(FragmentActivity.java:140)
        at androidx.fragment.app.FragmentActivity$$ExternalSyntheticLambda3.onContextAvailable(Unknown Source:2)
        at androidx.activity.contextaware.ContextAwareHelper.dispatchOnContextAvailable(ContextAwareHelper.java:99)
        at androidx.activity.ComponentActivity.onCreate(ComponentActivity.java:352)
        at androidx.fragment.app.FragmentActivity.onCreate(FragmentActivity.java:217)
        at com.example.plaques.MainActivity2.onCreate(MainActivity2.kt:8)
        at android.app.Activity.performCreate(Activity.java:8290)
        at android.app.Activity.performCreate(Activity.java:8269)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1384)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3657)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3813) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:101) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2308) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loopOnce(Looper.java:201) 
        at android.os.Looper.loop(Looper.java:288) 
        at android.app.ActivityThread.main(ActivityThread.java:7898) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936) 
2022-12-01 14:31:10.868 2297-2297/com.example.plaques I/Process: Sending signal. PID: 2297 SIG: 9

问题原因及解决方法 #

崩溃日志核心错误：You need to use a Theme.AppCompat theme (or descendant) with this activity，说明MainActivity2使用的Activity类与应用主题不匹配，解决步骤如下：

1. 检查MainActivity2的继承类 #

打开MainActivity2.kt，查看其继承关系：

• 如果继承的是AppCompatActivity，必须使用AppCompat或MaterialComponents主题；
• 如果继承的是ComponentActivity，可使用Material主题或AppCompat主题。

2. 修改主题配置 #

方法一：为MainActivity2单独设置主题

打开AndroidManifest.xml，找到MainActivity2的<activity>标签，添加android:theme属性：

<activity
    android:name=".MainActivity2"
    android:exported="false"
    android:theme="@style/Theme.MaterialComponents.DayNight.NoActionBar" />

方法二：修改全局主题

打开res/values/styles.xml（或res/values/themes.xml），将应用主题的父类改为AppCompat或MaterialComponents主题，例如：

<style name="Theme.Plaques" parent="Theme.MaterialComponents.DayNight.NoActionBar">
    <!-- 自定义主题属性 -->
    <item name="colorPrimary">@color/purple_500</item>
    <item name="colorPrimaryVariant">@color/purple_700</item>
    <item name="colorOnPrimary">@color/white</item>
</style>

3. 修正MainActivity的语法错误 #

原代码中的@Override是Java语法，Kotlin无需添加，需删除该注解，否则会导致编译错误。

内容的提问来源于stack exchange，提问作者Rems