Java 应用程序在使用显式意图时崩溃

我是Java编程的初学者。我在安卓工作室工作，有明确的意图。我遇到了一个非常恼人的问题，每当我试图使用intent启动quick_活动时，我的应用程序就会崩溃。Java代码和XML似乎都很好。以下是XML和Java：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:background="@drawable/quiz_front"
android:layout_height="match_parent"
tools:context="com.example.shujah.games.Quiz_front">


<Button
    android:id="@+id/start_quiz_btn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginBottom="78dp"
    android:text=""
    android:background="@android:color/transparent"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true" />

<Button
    android:id="@+id/from_quiz_front_to_menu_btn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"

    android:background="@android:color/transparent"
    android:textColor="@color/colorAccent"
    android:layout_alignLeft="@+id/start_quiz_btn"
    android:layout_alignParentBottom="true"
    android:layout_alignStart="@+id/start_quiz_btn"
    android:text="BACK" />

  </RelativeLayout>

以下是我想参加的活动：

  public class Quiz_activity extends AppCompatActivity {
 TextView choice1;
 TextView choice2;
 TextView choice3;
 TextView choice4;
 TextView num_right;
 TextView num_left;
 TextView sign;
 TextView score;
 Random r;
 int scor;
 Intent ii;
 Button back_to_front;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_quiz_activity);





    back_to_front.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            ii = new Intent(getApplicationContext(), Quiz_front.class);
            startActivity(ii);

        }
    });

    choice1 = (TextView) findViewById(R.id.choice1_tv);
    choice2 = (TextView) findViewById(R.id.choice2_tv);
    choice3 = (TextView) findViewById(R.id.choice3_tv);
    choice4 = (TextView) findViewById(R.id.choice4_tv);
    num_left = (TextView) findViewById(R.id.left_tv);
    num_right = (TextView) findViewById(R.id.right_tv);
    score = (TextView) findViewById(R.id.score_tv);
    sign = (TextView) findViewById(R.id.sign_tv);
    r = new Random();

   /* choice1.setTextColor(Color.BLUE);
    choice2.setTextColor(Color.BLUE);
    choice3.setTextColor(Color.BLUE);
    choice4.setTextColor(Color.BLUE);
    num_right.setTextColor(Color.YELLOW);
    num_left.setTextColor(Color.YELLOW);
    sign.setTextColor(Color.YELLOW);*/

    }
 }

XML:

以下是Android Manifest.XML：

 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.example.shujah.games">

 <application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MenuActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name="com.example.shujah.games.RPSactivity" />
    <activity android:name="com.example.shujah.games.Quiz_activity" />
    <activity android:name="com.example.shujah.games.Quiz_front"></activity>
  </application>

 </manifest>

将back\u添加到\u front=按钮findviewbydr.id.back\u添加到\u question\u front

以前

back_to_front.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            ii = new Intent(getApplicationContext(), Quiz_front.class);
            startActivity(ii);

        }
    });

---

经常发布异常的StackTraceTachanx。这是我的一个相当业余的错误。无论如何，thnx

 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.example.shujah.games">

 <application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MenuActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name="com.example.shujah.games.RPSactivity" />
    <activity android:name="com.example.shujah.games.Quiz_activity" />
    <activity android:name="com.example.shujah.games.Quiz_front"></activity>
  </application>

 </manifest>

back_to_front.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            ii = new Intent(getApplicationContext(), Quiz_front.class);
            startActivity(ii);

        }
    });