Hello, I'm new to android, and when I try to run my app, these errors:
08-15 18:10:49.828: E/AndroidRuntime(1769): FATAL EXCEPTION: main
08-15 18:10:49.828: E/AndroidRuntime(1769): java.lang.RuntimeException: Unable to start activity ComponentInfo{br.com.example.ifagenda/br.com.example.ifagenda.PessoaPrincipal}: java.lang.NullPointerException
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.os.Handler.dispatchMessage(Handler.java:99)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.os.Looper.loop(Looper.java:130)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.ActivityThread.main(ActivityThread.java:3683)
08-15 18:10:49.828: E/AndroidRuntime(1769): at java.lang.reflect.Method.invokeNative(Native Method)
08-15 18:10:49.828: E/AndroidRuntime(1769): at java.lang.reflect.Method.invoke(Method.java:507)
08-15 18:10:49.828: E/AndroidRuntime(1769): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
08-15 18:10:49.828: E/AndroidRuntime(1769): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
08-15 18:10:49.828: E/AndroidRuntime(1769): at dalvik.system.NativeStart.main(Native Method)
08-15 18:10:49.828: E/AndroidRuntime(1769): Caused by: java.lang.NullPointerException
08-15 18:10:49.828: E/AndroidRuntime(1769): at br.com.example.ifagenda.PessoaConexaoBanco.listarPessoas(PessoaConexaoBanco.java:46)
08-15 18:10:49.828: E/AndroidRuntime(1769): at br.com.example.ifagenda.PessoaPrincipal.onCreate(PessoaPrincipal.java:16)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
08-15 18:10:49.828: E/AndroidRuntime(1769): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
08-15 18:10:49.828: E/AndroidRuntime(1769): ... 11 more
What can it be?
package br.com.example.ifagenda;
import java.util.List;
import android.app.ListActivity;
import android.os.Bundle;
public class PessoaPrincipal extends ListActivity {
public static PessoaConexaoBanco pessoaConexaoBanco;
private List<Pessoa> pessoas;
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
pessoaConexaoBanco = new PessoaConexaoBanco(this);
pessoas = pessoaConexaoBanco.listarPessoas();
// customizando para inserir linha a linha os registros das pessoas
setListAdapter(new PessoaListAdapter(this, pessoas));
}
}
package br.com.example.ifagenda;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
public class PessoaConexaoBanco {
protected SQLiteDatabase bancoDados = null;
public PessoaConexaoBanco(Context context) {
bancoDados = context.openOrCreateDatabase("dbalunos", Context.MODE_PRIVATE, null);
String sqlCriaTabela = " CREATE TABLE IF NOT EXISTS pessoas" +
"(_id INTEGER PRIMARY KEY autoincrement, nome TEXT , endereco TEXT" +
"telefone TEXT);";
bancoDados.execSQL(sqlCriaTabela);
//String adicionarRegistros = "insert into pessoas (nome, endereco, telefone) values" +
// "('Gabriel','Rua Gibaut','123456')";
//bancoDados.execSQL(adicionarRegistros);
}
// metodo que retorna as pessoas da db
public Cursor getCursor(){
try {
return bancoDados.query("pessoas",
//new String[] {"nome", "endereco","telefone"},
//or do
Pessoa.colunas,
null,//selection,
null,//selectionArgs,
null,//groupBy,
null,//having
null,//"order by nome"//orderBy)
null); //Limite de registros retornados
} catch (SQLException erro) {
return null;
}
}
// metodo que retornará a lista das pessoas
public List<Pessoa> listarPessoas() {
Cursor cursor = getCursor();
List<Pessoa> listPessoas = new ArrayList<Pessoa>();
if (cursor.moveToFirst()) {
int indexId = cursor.getColumnIndex(Pessoa._ID);
int indexNome = cursor.getColumnIndex(Pessoa.NOME);
int indexEndereco = cursor.getColumnIndex(Pessoa.ENDERECO);
int indexTelefone = cursor.getColumnIndex(Pessoa.TELEFONE);
do{
Pessoa pessoa = new Pessoa();
listPessoas.add(pessoa);
pessoa.id = cursor.getLong(indexId);
pessoa.nome = cursor.getString(indexNome);
pessoa.endereco = cursor.getString(indexEndereco);
pessoa.telefone = cursor.getString(indexTelefone);
}
while (cursor.moveToNext());
}
return listPessoas;
}
}
Now it appeared:
08-16 22:42:44.823: W/System.err(1374): android.database.sqlite.SQLiteException: no such column: telefone: , while compiling: SELECT _id, nome, endereco, telefone FROM pessoas
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:92)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:65)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:83)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:49)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1356)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1235)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1189)
08-16 22:42:44.823: W/System.err(1374): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1309)
08-16 22:42:44.823: W/System.err(1374): at br.com.example.ifagenda.PessoaConexaoBanco.getCursor(PessoaConexaoBanco.java:29)
08-16 22:42:44.823: W/System.err(1374): at br.com.example.ifagenda.PessoaConexaoBanco.listarPessoas(PessoaConexaoBanco.java:46)
08-16 22:42:44.823: W/System.err(1374): at br.com.example.ifagenda.PessoaPrincipal.onCreate(PessoaPrincipal.java:16)
08-16 22:42:44.823: W/System.err(1374): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
08-16 22:42:44.823: W/System.err(1374): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
08-16 22:42:44.823: W/System.err(1374): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
08-16 22:42:44.823: W/System.err(1374): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
08-16 22:42:44.823: W/System.err(1374): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
08-16 22:42:44.823: W/System.err(1374): at android.os.Handler.dispatchMessage(Handler.java:99)
08-16 22:42:44.823: W/System.err(1374): at android.os.Looper.loop(Looper.java:130)
08-16 22:42:44.823: W/System.err(1374): at android.app.ActivityThread.main(ActivityThread.java:3683)
08-16 22:42:44.823: W/System.err(1374): at java.lang.reflect.Method.invokeNative(Native Method)
08-16 22:42:44.823: W/System.err(1374): at java.lang.reflect.Method.invoke(Method.java:507)
08-16 22:42:44.823: W/System.err(1374): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
08-16 22:42:44.823: W/System.err(1374): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
08-16 22:42:44.823: W/System.err(1374): at dalvik.system.NativeStart.main(Native Method)
08-16 22:42:44.823: D/AndroidRuntime(1374): Shutting down VM
08-16 22:42:44.823: W/dalvikvm(1374): threadid=1: thread exiting with uncaught exception (group=0xb58394f0)