我不能'；更新到java 8后，无法修复某些异常

更新到java 8后，应用程序不会启动。gradle构建工作正常。当我试图在emulator上启动我的应用程序时，它崩溃了，我得到了stacktrace，您可以在下面看到：

` Process: com.blackmamba.gopgame, PID: 1873
    java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.blackmamba.gopgame/com.blackmamba.gopgame.MainMenu}: java.lang.ClassNotFoundException: Didn't find class "com.blackmamba.gopgame.MainMenu" on path: DexPathList[[zip file "/data/app/com.blackmamba.gopgame-2/base.apk"],nativeLibraryDirectories=[/vendor/lib64, /system/lib64]]
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2209)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
     Caused by: java.lang.ClassNotFoundException: Didn't find class "com.blackmamba.gopgame.MainMenu" on path: DexPathList[[zip file "/data/app/com.blackmamba.gopgame-2/base.apk"],nativeLibraryDirectories=[/vendor/lib64, /system/lib64]]
            at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
            at android.app.Instrumentation.newActivity(Instrumentation.java:1065)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2199)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
    Suppressed: java.lang.ClassNotFoundException: com.blackmamba.gopgame.MainMenu
            at java.lang.Class.classForName(Native Method)
            at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
            at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
            ... 13 more
     Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available`

在这里您可以看到build.gradle：

buildscript {    
    repositories {
        mavenCentral()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:1.2.3'
        }
    }

apply plugin: 'com.android.application'
    repositories {
        mavenCentral()
        mavenLocal()
    }
    android {
       lintOptions {
           abortOnError false
       }

       compileSdkVersion 21
       buildToolsVersion "22.0.1"

       defaultConfig {
           applicationId "com.blackmamba.gopgame"
           minSdkVersion 14
           targetSdkVersion 21
           versionCode 1
           versionName "1.0"
       }

       sourceSets {
           main {
               manifest.srcFile 'AndroidManifest.xml'
               resources.srcDirs = ['src']
               res.srcDirs = ['res']
           }
       }
       compileOptions {
           sourceCompatibility JavaVersion.VERSION_1_7
           targetCompatibility JavaVersion.VERSION_1_7
       }
    }

    dependencies {
        compile 'com.android.support:appcompat-v7:22.1.1'
        compile 'com.android.support:support-v13:22.1.1'
    }

以及我的AndroidManifest.xml：

<?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.blackmamba.gopgame"
          android:versionCode="1"
          android:versionName="1.0">

    <uses-sdk android:minSdkVersion="14" android:targetSdkVersion="21"/>
    <application
        android:label="@string/app_name"
        android:icon="@drawable/ic_launcher"
        android:screenOrientation="portrait">
        <activity
            android:name="MainMenu"
            android:label="@string/app_name"
            android:theme="@style/Theme.AppCompat.NoActionBar" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <activity android:name="HeroSelector"
                  android:theme="@style/Theme.AppCompat.NoActionBar"/>
    </application>
</manifest>

---

项目树->

Android不支持Java 8：

---

Android仍然不支持Java 8，因为Android不使用Java虚拟机，而是使用一个完全独立的名为Dalvik的虚拟机，这就是为什么添加对Java 8的支持需要很长时间和成本，因为它需要从头开始进行更改。

change

Android:name=“MainMenu”

使用

android:name=“.main menu”

我已经试过了，但是没有用。你能显示你的项目树或

main menu

类吗？是的，我已经更新了问题主体。

package com.blackmamba.gopgame;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainMenu extends Activity {
    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Button exitButton = (Button)findViewById(R.id.exit_button);
        exitButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                finish();
            }
        });

        Button newGameButton = (Button)findViewById(R.id.new_game_button);
        newGameButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(MainMenu.this, HeroSelector.class);
                startActivity(intent);
            }
        });

    }
}