无法找到显式活动类

Question

我刚刚开始android开发，我被这个问题困住了。当应用程序运行时，我看到以下内容:

https://i.stack.imgur.com/EA6Nr.jpg

(如果链接断开或无法看到图像，它只是一个横向模式下的菜单，有三个按钮)

这就是我想看到的。然而，当我点击"开始播放"(这应该会导致android模拟器进入空白屏幕)时，模拟器退出了我们的应用程序，并说:"不幸的是，主菜单已停止。"

这是我在LogCat中得到的错误:

04-15 21:49:08.779: W/dalvikvm(985): threadid=1: thread exiting with uncaught exception 
(group=0x409961f8)
04-15 17:56:24.539: E/AndroidRuntime(739): FATAL EXCEPTION: main
04-15 17:56:24.539: E/AndroidRuntime(739):
android.content.ActivityNotFoundException: Unable to find explicit activity class
{com.example.quote.board/android.inputmethodservice.Keyboard}; have you declared this
activity in your AndroidManifest.xml?
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1508)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.app.Instrumentation.execStartActivity(Instrumentation.java:1384)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.app.Activity.startActivityForResult(Activity.java:3190)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.app.Activity.startActivity(Activity.java:3297)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
com.example.quote.board.MainMenu$1.onClick(MainMenu.java:30)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.view.View.performClick(View.java:3480)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.view.View$PerformClick.run(View.java:13983)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.os.Handler.handleCallback(Handler.java:605)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.os.Handler.dispatchMessage(Handler.java:92)
04-15 17:56:24.539: E/AndroidRuntime(739):  at android.os.Looper.loop(Looper.java:137)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
android.app.ActivityThread.main(ActivityThread.java:4340)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
java.lang.reflect.Method.invokeNative(Native Method)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
java.lang.reflect.Method.invoke(Method.java:511)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
04-15 17:56:24.539: E/AndroidRuntime(739):  at 
dalvik.system.NativeStart.main(NativeMethod)

我目前有两个类。这是我的第一个类，名为MainMenu:

package com.example.quote.board;
import android.inputmethodservice.Keyboard;
import android.os.Bundle;
import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainMenu extends Activity {
    @SuppressLint({ "NewApi", "NewApi", "NewApi" })
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main_menu);
    ActionBar action= getActionBar();
    action.hide();
    Button startPlaying = (Button) findViewById(R.id.startPlaying);
    Button specialKeyboard = (Button) findViewById(R.id.specialKeyboards);
    Button info = (Button) findViewById(R.id.info);
    startPlaying.setOnClickListener(new OnClickListener(){
        public void onClick(View v){
            Intent intent = new Intent(getApplicationContext(), Keyboard.class);
            startActivity(intent);
        }
    });
}
}

我的另一个类叫做Keyboard:

package com.example.quote.board;
import android.app.ActionBar;
import android.app.Activity;
import android.os.Bundle;
public class Keyboard extends Activity{
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.keyboard);
    ActionBar action = getActionBar();
    action.hide();
}

}

这是我的AndroidManifest.xml文件:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.quote.board"
    android:versionCode="1"
    android:versionName="1.0" >
    <uses-sdk
        android:minSdkVersion="11"
        android:targetSdkVersion="15" />
    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme"
         >
        <activity
            android:name=".MainMenu"
            android:screenOrientation="landscape"
            android:label="@string/title_activity_main_menu" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name="com.example.quote.board.Keyboard"
            android:screenOrientation="landscape"
            android:label="@string/app_name" >
       </activity>
    </application>
</manifest>

顺便说一下，我一直在和我的朋友一起做这个，他在一台windows电脑上工作。我们用git把文件传送给我。此外，这个应用程序完美地为他工作。

Answer 1

解决方案"是否声明了这个活动在你的AndroidManifest.xml?"写在manifest.xml

<activity android:name=".nameOfYourActivity"> </activity>

Answer 2

修复导入:您在主菜单源中的导入不正确。你写的是:import android.inputmethodservice.Keyboard;但是你需要:com.example.quote.board.Keyboard