Question

任何人都可以帮我解决我在Android项目中遇到的错误吗？

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

  <TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/addButton"
    android:layout_alignParentTop="true"
    android:textColor="#00f"
    android:layout_gravity="center"
    android:text="Student Records Application" />

  <TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/textView1"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="15dp"
    android:layout_gravity="center"
    android:text="Select What you would like to do" />

<Button
    android:id="@+id/addButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/textView1"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="15dp"
    android:layout_gravity="center"
    android:text="Add New Records" />



<Button
    android:id="@+id/editButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/addButton"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="15dp"
    android:layout_gravity="center"
    android:text="Edit Student Records" />

<Button
    android:id="@+id/deleteButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/editButton"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="15dp"
    android:layout_gravity="center"
    android:text="Delete Student Records" />

   </LinearLayout>

    package com.example.studentrecord;

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

public class MainActivity extends Activity {
Button addButton;
Button editButton;
Button deleteButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        addButton=(Button)findViewById(R.id.addButton);
        addButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Toast.makeText(MainActivity.this, "Going to add Record Activity", Toast.LENGTH_LONG).show();
                startActivity(new Intent(MainActivity.this, Add_Student.class));
            }
        });
        editButton=(Button)findViewById(R.id.editButton);
        editButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Toast.makeText(MainActivity.this, "Going to Edit Record Activity", Toast.LENGTH_LONG).show();
                setContentView(R.layout.activity_edit_student);
                startActivity(new Intent(MainActivity.this, EditStudent.class));
            }
        });
        deleteButton=(Button)findViewById(R.id.deleteButton);
        deleteButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Toast.makeText(MainActivity.this, "Going to Delete Record Activity", Toast.LENGTH_LONG).show();
                startActivity(new Intent(MainActivity.this, Delete_Student.class));
            }
        });



    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

上面的布局和代码包含在主要活动中。

    package com.example.studentrecord;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class DatabaseManager {
    public static final String DB_NAME="student";
    public static final String DB_TABLE="StudentInfo";
    public static final int DB_VERSION=1;
    private static final String CREATE_TABLE="CREATE TABLE" + DB_TABLE + "studentId INTEGER PRIMARY KEY, firstName TEXT, lastName TEXT, gender TEXT, course TEXT. age INTEGER);";
    private SQLHelper helper;
    private SQLiteDatabase db;
    private Context context;

    public DatabaseManager(Context c) {
        this.context=c;
        helper=new SQLHelper(c);
        this.db=helper.getReadableDatabase();
    }

    public DatabaseManager openReadable() throws android.database.SQLException {
        helper=new SQLHelper(context);
        db=helper.getReadableDatabase();
        return this;
    }

    public void close() {
        helper.close();
    }

    public Boolean addRow(Integer a, String b, String c, String d, String e, Integer f) {
        ContentValues newStudent = new ContentValues();
        newStudent.put("studentId", a);
        newStudent.put("firstName", b);
        newStudent.put("lastName",c);
        newStudent.put("gender",d);
        newStudent.put("course",e);
        newStudent.put("age", f);

        try {
            db.insertOrThrow(DB_TABLE, null, newStudent);
        }
        catch(Exception e1){
            Log.e("Error in inserting row", e1.toString());
            e1.printStackTrace();
            return false;
        }
        db.close();
        return true;
    }

    public String retrieveRows() {
        String[] columns = new String[] {"studentId","firstName","lastName","gender","course","age"};
        Cursor cursor=db.query(DB_TABLE, columns, null, null, null, null, null);
        String tableRows="";
        cursor.moveToFirst();
        while (cursor.isAfterLast()==false) {
            tableRows=tableRows + cursor.getInt(0) + "," + cursor.getString(1)+ "," +cursor.getString(2)+","+cursor.getString(3)+","+cursor.getString(4)+","+cursor.getInt(5) + "\n";
            cursor.moveToNext();
        }
        if(cursor!=null && !cursor.isClosed()) {
            cursor.close();
        }
        return tableRows;
    }

    public class SQLHelper extends SQLiteOpenHelper {
        public SQLHelper(Context c) {
            super(c, DB_NAME, null, DB_VERSION);
        }
        @Override
        public void onCreate(SQLiteDatabase db){
            db.execSQL(CREATE_TABLE);
        }
        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
            Log.w("Students table", "Upgrading database i.e. dropping table and recreating it");
        }

    }

}

上面的代码包含在我的数据库管理器文件中

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:textSize="15sp"
        android:textColor="#33f"
        android:background="#cfcfcf"
        android:text="Add a student Record" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0"
            android:text="Student Id" />

        <EditText
            android:id="@+id/studentId"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0.5"
            android:layout_marginLeft="30dp"
            android:inputType="number"
            android:ems="10" >


        </EditText>


    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/textView3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0"
            android:text="First Name" />

        <EditText
            android:id="@+id/fName"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0.5"
            android:layout_marginLeft="25dp"
            android:inputType="text"
            android:ems="10" >


        </EditText>


    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" 
        android:orientation="horizontal">
        <TextView
            android:id="@+id/textView3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0"
            android:text="Last Name" />

        <EditText
            android:id="@+id/lName"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0.5"
            android:inputType="text"
            android:layout_marginLeft="25dp"
            android:ems="10" >


        </EditText>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" 
        android:orientation="horizontal">
        <TextView
            android:id="@+id/textView4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0"
            android:text="Gender" />

        <Spinner
            android:id="@+id/spinnerGender"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0.5" 
            android:scrollbarSize="5sp"
            android:layout_marginLeft="45dp"
            android:entries="@array/Gender_Array"/>


    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" 
        android:orientation="horizontal">
        <TextView
            android:id="@+id/textView5"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0"
            android:text="Course" />

        <Spinner
            android:id="@+id/spinnerCourse"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0.5" 
            android:scrollbarSize="5sp"
            android:layout_marginLeft="45dp"
            android:entries="@array/Course_Array"/>


    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" 
        android:orientation="horizontal">
        <TextView
            android:id="@+id/textView6"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0"
            android:text="Age" />

        <EditText
            android:id="@+id/age"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="0.5"
            android:inputType="number"
            android:layout_marginLeft="60dp"
            android:ems="10" >


        </EditText>
    </LinearLayout>



    <Button
        android:id="@+id/buttonSubmit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="75dp"
        android:text="Submit" />



    <TextView
        android:id="@+id/response"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="" />

</LinearLayout>



 package com.example.studentrecord;

import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.view.Menu;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import android.view.View.OnClickListener;


public class Add_Student extends Activity {
    private DatabaseManager mydManager;
    private TextView response;
    private EditText studentId, fName, lName, age;
    private Button submit;
    private Boolean recordInsert;
    private Spinner gender, course;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_add__student);
        response=(TextView)findViewById(R.id.response);
        submit=(Button)findViewById(R.id.buttonSubmit);



        submit.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                //Toast 

                Toast.makeText(Add_Student.this, "clicked" , Toast.LENGTH_LONG).show();


                mydManager = new DatabaseManager(Add_Student.this);
                studentId=(EditText)findViewById(R.id.studentId);
                fName=(EditText)findViewById(R.id.fName);
                lName=(EditText)findViewById(R.id.lName);
                gender=(Spinner)findViewById(R.id.spinnerGender);
                course=(Spinner)findViewById(R.id.spinnerCourse);
                age=(EditText)findViewById(R.id.age);

                recordInsert=mydManager.addRow(Integer.parseInt(studentId.getText().toString()), fName.getText().toString(), lName.getText().toString(), gender.getSelectedItem().toString(), course.getSelectedItem().toString(), Integer.parseInt(age.getText().toString()));
                if (recordInsert){
                    response.setText("The row is inserted");
                }
                else
                {
                    response.setText("Sorry, database could not be inserted");
                }
                InputMethodManager imm=(InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.hideSoftInputFromWindow(studentId.getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
                mydManager.close();
                studentId.setText("");
                fName.setText("");
                lName.setText("");
                gender.setSelection(0);
                course.setSelection(0);
                age.setText("");


            }
        });


    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.add__student, menu);
        return true;
    }

}

在我执行提交按钮之前，一切都很好，应用程序崩溃了。有人能发现错误吗？

FYI控制台中没有错误。每当我执行提交按钮时，只有应用程序崩溃了感谢

日志文件

09-22 22:44:50.737: D/dalvikvm(1297): GC_FOR_ALLOC freed 26K, 6% free 4192K/4428K, paused 19ms, total 20ms
09-22 22:44:50.767: D/dalvikvm(1297): GC_FOR_ALLOC freed 3K, 6% free 4445K/4692K, paused 20ms, total 21ms
09-22 22:44:52.657: I/Choreographer(1297): Skipped 42 frames!  The application may be doing too much work on its main thread.
09-22 22:44:53.267: E/SQLiteLog(1297): (1) near "TABLEStudentInfostudentId": syntax error
09-22 22:44:53.267: D/AndroidRuntime(1297): Shutting down VM
09-22 22:44:53.267: W/dalvikvm(1297): threadid=1: thread exiting with uncaught exception (group=0xb3af6b90)
09-22 22:44:53.287: E/AndroidRuntime(1297): FATAL EXCEPTION: main
09-22 22:44:53.287: E/AndroidRuntime(1297): Process: com.example.studentrecord, PID: 1297
09-22 22:44:53.287: E/AndroidRuntime(1297): android.database.sqlite.SQLiteException: near "TABLEStudentInfostudentId": syntax error (code 1): , while compiling: CREATE TABLEStudentInfostudentId INTEGER PRIMARY KEY, firstName TEXT, lastName TEXT, gender TEXT, course TEXT. age INTEGER);
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:889)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:500)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1672)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1603)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at com.example.studentrecord.DatabaseManager$SQLHelper.onCreate(DatabaseManager.java:77)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:252)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:188)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at com.example.studentrecord.DatabaseManager.<init>(DatabaseManager.java:22)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at com.example.studentrecord.Add_Student$1.onClick(Add_Student.java:43)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.view.View.performClick(View.java:4424)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.view.View$PerformClick.run(View.java:18383)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.os.Handler.handleCallback(Handler.java:733)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.os.Handler.dispatchMessage(Handler.java:95)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.os.Looper.loop(Looper.java:137)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at android.app.ActivityThread.main(ActivityThread.java:4998)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at java.lang.reflect.Method.invokeNative(Native Method)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at java.lang.reflect.Method.invoke(Method.java:515)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
09-22 22:44:53.287: E/AndroidRuntime(1297):     at dalvik.system.NativeStart.main(Native Method)
09-22 22:44:56.597: D/gralloc_goldfish(1332): Emulator without GPU emulation detected.

Answer 1

您需要在CREATE TABLE和表名之间放置一个空格并修复一些其他语法错误，然后才能正确解析SQL：

private static final String CREATE_TABLE="CREATE TABLE " + DB_TABLE + 
" (studentId INTEGER PRIMARY KEY, firstName TEXT, lastName TEXT, gender TEXT, 
course TEXT, age INTEGER);";

SQLite崩溃的Android数据输入

1 个答案: