我一直在使用android studio来制作测验应用程序。我正在尝试进行测验应用程序。在一天之前应用程序运行正常但是当我今天尝试运行它时，我得到运行时异常。我没有收到任何错误。发生以下异常..
AndroidRuntime﹕ FATAL EXCEPTION: main
Process: login.com.quiz1, PID: 2279
java.lang.RuntimeException: Unable to start activity ComponentInfo{login.com.quiz1/login.com.quiz1.MainActivity}: java.lang.IllegalStateException: getDatabase called recursively
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.IllegalStateException: getDatabase called recursively
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:203)
at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
at login.com.quiz1.DbHelper.addQuestion(DbHelper.java:71)
at login.com.quiz1.DbHelper.addQuestions(DbHelper.java:41)
at login.com.quiz1.DbHelper.onCreate(DbHelper.java:35)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:251)
at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:187)
at login.com.quiz1.DbHelper.getAllQuestions(DbHelper.java:87)
at login.com.quiz1.MainActivity.onCreate(MainActivity.java:30)
at android.app.Activity.performCreate(Activity.java:6237)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
12-16 21:03:40.813 2279-2286/login.com.quiz1 W/art﹕ Suspending all threads took: 11.315ms
12-16 21:07:53.961 2279-2279/? I/Process﹕ Sending signal. PID: 2279 SIG: 9
以下是启动测验时崩溃的java / activity文件：
package login.com.quiz1;
import java.util.List;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
public class MainActivity extends Activity {
List<Question> quesList;
int score=0;
int qid=0;
Question currentQ;
TextView txtQuestion;
RadioButton rda, rdb, rdc,rdd;
Button butNext;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
DbHelper db=new DbHelper(this);
quesList=db.getAllQuestions();
currentQ=quesList.get(qid);
txtQuestion=(TextView)findViewById(R.id.textView1);
rda=(RadioButton)findViewById(R.id.radio0);
rdb=(RadioButton)findViewById(R.id.radio1);
rdc=(RadioButton)findViewById(R.id.radio2);
rdd=(RadioButton)findViewById(R.id.radio3);
butNext=(Button)findViewById(R.id.button1);
setQuestionView();
butNext.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
RadioGroup grp=(RadioGroup)findViewById(R.id.radioGroup1);
RadioButton answer=(RadioButton)findViewById(grp.getCheckedRadioButtonId());
Log.d("yourans", currentQ.getANSWER()+" "+answer.getText());
if(currentQ.getANSWER().equals(answer.getText()))
{
score++;
Log.d("score", "Your score"+score);
}
if(qid<7){
currentQ=quesList.get(qid);
setQuestionView();
}else{
Intent intent = new Intent(MainActivity.this, ResultActivity.class);
Bundle b = new Bundle();
b.putInt("score", score); //Your score
intent.putExtras(b); //Put your score to your next Intent
startActivity(intent);
finish();
}
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
private void setQuestionView()
{
txtQuestion.setText(currentQ.getQUESTION());
rda.setText(currentQ.getOPTA());
rdb.setText(currentQ.getOPTB());
rdc.setText(currentQ.getOPTC());
rdd.setText(currentQ.getOPTD());
qid++;
}
}
这是我的xml文件
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:background="@drawable/creatorb2">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<RadioGroup
android:id="@+id/radioGroup1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="0.04"
>
<RadioButton
android:id="@+id/radio0"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:checked="false"
android:text="RadioButton" />
<RadioButton
android:id="@+id/radio1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="RadioButton" />
<RadioButton
android:id="@+id/radio2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="RadioButton" />
<RadioButton
android:id="@+id/radio3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="RadioButton" />
</RadioGroup>
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:src="@drawable/logo" />
<Button
android:id="@+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/str_next" />
</LinearLayout>
</RelativeLayout>
DBHelper
public class DbHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "Quiz";
// tasks table name
private static final String TABLE_QUEST = "quest";
// tasks Table Columns names
private static final String KEY_ID = "id";
private static final String KEY_QUES = "question";
private static final String KEY_ANSWER = "answer"; //correct option
private static final String KEY_OPTA= "opta"; //option a
private static final String KEY_OPTB= "optb"; //option b
private static final String KEY_OPTC= "optc"; //option c
private static final String KEY_OPTD= "optd"; //option d
private SQLiteDatabase dbase;
public DbHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
dbase=db;
String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_QUEST + " ( "
+ KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_QUES
+ " TEXT, " + KEY_ANSWER+ " TEXT, "+KEY_OPTA +" TEXT, "
+KEY_OPTB +" TEXT, "+KEY_OPTC+" TEXT,"+ KEY_OPTD+" TEXT)";
db.execSQL(sql);
addQuestions();
//db.close();
}
private void addQuestions()
{
Question q1=new Question("1.A fruit seller had some apples. He sells 40% apples and still has 420 apples. Originally, he had:?","588 apples", "600 apples", "672 apples","600 apples","588 apples");
this.addQuestion(q1);
//correct ans-588
Question q2=new Question("2.The square root of (7 + 35) (7 - 35) is", "2","5","2","4","35");
this.addQuestion(q2);
//correct ans-2
Question q3=new Question("3.A man buys a cycle for Rs. 1400 and sells it at a loss of 15%. What is the selling price of the cycle?", "1190", "1160", "1190", "1202","1090");
this.addQuestion(q3);
//correct ans-1190
Question q4=new Question("4.Which of the following is a prime number", "91", "31", "61", "71","91");
this.addQuestion(q4);
//correct ans-91
Question q5=new Question("5.If 144/0.144 = 14.4/x, then the value of x is:?","0.0144", "1.44","14.4", "144","0.0144" );
this.addQuestion(q5);
//correct ans-0.0144
Question q6=new Question("6.If mean and median for a particular experiment is 101 and 100 respectively find the mode","98", "99", "100","101","98");
this.addQuestion(q6);
//correct ans-98
Question q7=new Question("7.Find the odd man out 6, 9, 15, 21, 24, 28, 30?","28","21","24","30","28");
this.addQuestion(q7);
//correct ans-28
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldV, int newV) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUEST);
// Create tables again
onCreate(db);
}
// Adding new question
public void addQuestion(Question quest) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_QUES, quest.getQUESTION());
values.put(KEY_ANSWER, quest.getANSWER());
values.put(KEY_OPTA, quest.getOPTA());
values.put(KEY_OPTB, quest.getOPTB());
values.put(KEY_OPTC, quest.getOPTC());
values.put(KEY_OPTD, quest.getOPTD());
// Inserting Row
dbase.insert(TABLE_QUEST, null, values);
}
public List<Question> getAllQuestions() {
List<Question> quesList = new ArrayList<Question>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_QUEST;
dbase=this.getReadableDatabase();
Cursor cursor = dbase.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Question quest = new Question();
quest.setID(cursor.getInt(0));
quest.setQUESTION(cursor.getString(1));
quest.setANSWER(cursor.getString(6));
quest.setOPTA(cursor.getString(2));
quest.setOPTB(cursor.getString(3));
quest.setOPTC(cursor.getString(4));
quest.setOPTD(cursor.getString(5));
quesList.add(quest);
} while (cursor.moveToNext());
}
// return quest list
return quesList;
}
public int rowcount()
{
int row=0;
String selectQuery = "SELECT * FROM " + TABLE_QUEST;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
row=cursor.getCount();
return row;
}
}
答案 0 :(得分：0)
txtQuestion.setText(currentQ.getQUESTION());
你的问题课在哪里？ 和DbHelper
在我看来，你是在递归地调用getDatabase方法（可能通过你的dbHelper）。正如它在Log上清楚地说的那样：
Caused by: java.lang.IllegalStateException: getDatabase called recursively
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:203)
锁定这些代码行：
at login.com.quiz1.DbHelper.addQuestion(DbHelper.java:71)
at login.com.quiz1.DbHelper.addQuestions(DbHelper.java:41)
at login.com.quiz1.DbHelper.onCreate(DbHelper.java:35)
答案 1 :(得分：0)
请勿在{{1}}：
中执行此操作onCreate让SQLiteOpenHelper完成创建数据库，然后添加一个单独的方法 SQLiteDatabase db = this.getWritableDatabase();
来处理数据库
如果您需要预填充数据库，只需执行您的语句而无需获取可写的数据库实例 - 您已经在onCreate中传递了一个