我创建了一个应用程序来连接到现有的sqlite数据库，并显示来自数据库的一些基本信息..但它在我的模拟器中意外关闭，我不确定错误是什么意思。 db只有两个表，Information和android_metadata。
我在项目文件中遇到的唯一错误是在AndroidManifest.xml中。它说：“属性minSdkVersion（8）低于项目目标API级别（10）”其他SO帖子说这可以忽略，所以我没有编辑它（它似乎不是它的问题logcat跟踪。）
这是使用db：中的'states'colunn填充listview的活动：
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import healthy.com.sdp.R;
import healthy.com.sdp.db.DataBaseHelper;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.SQLException;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
public class StateListActivity extends Activity {
private ListView _listView;
private List<StateDisease> stateNames = new ArrayList<StateDisease>();
DataBaseHelper myDbHelper;
AlertDialog.Builder builder ;
AlertDialog alert;
Context _context;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.state_list);
myDbHelper = new DataBaseHelper(this);
_listView = (ListView) findViewById(R.id.listState);
_listView.setAdapter(new SingleTextAdapter(getBaseContext(), R.layout.adapter_single_text, stateNames));
_listView.setOnItemClickListener(clickListener);
_context = this;
try {
myDbHelper.createDataBase();
} catch (IOException ioe) {
throw new Error("Unable to create database");
}
try {
myDbHelper.openDataBase();
Cursor cursor = myDbHelper.executeRawQuery("Select * from Information");
if(cursor.moveToFirst())
{
while (cursor.isAfterLast() == false)
{
StateDisease sd = new StateDisease();
sd._stateId = cursor.getInt(cursor.getColumnIndex("_id"));
sd._percentHeartDisease = cursor.getDouble(cursor.getColumnIndex("HeartDisease"));
sd._percentObesity = cursor.getDouble(cursor.getColumnIndex("Obesity"));
sd._stateName = cursor.getString(cursor.getColumnIndex("States"));
sd._percentLungDisease = cursor.getDouble(cursor.getColumnIndex("LungDisease"));
stateNames.add(sd);
cursor.moveToNext();
}
}
myDbHelper.close();
}catch(SQLException sqle){
throw sqle;
}
}
private OnItemClickListener clickListener = new OnItemClickListener()
{
@Override
public void onItemClick(AdapterView<?> parent, View v, int pos,
long id) {
Intent intent = new Intent(getBaseContext(), DiseaseSelectionActivity.class);
Bundle b = new Bundle();
b.putInt(Constant.STATE_ID, stateNames.get(pos)._stateId);
b.putString(Constant.STATE_NAME, stateNames.get(pos)._stateName);
intent.putExtras(b);
startActivity(intent);
}
};
}
这是logcat跟踪：
03-11 07:14:33.013: I/Database(336): sqlite returned: error code = 1, msg = no such table: Information
03-11 07:14:33.013: W/System.err(336): android.database.sqlite.SQLiteException: no such table: Information: , while compiling: Select * from Information
03-11 07:14:33.022: W/System.err(336): at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method)
03-11 07:14:33.022: W/System.err(336): at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:92)
03-11 07:14:33.022: W/System.err(336): at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:65)
03-11 07:14:33.022: W/System.err(336): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:83)
03-11 07:14:33.022: W/System.err(336): at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:49)
03-11 07:14:33.032: W/System.err(336): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42)
03-11 07:14:33.032: W/System.err(336): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1356)
03-11 07:14:33.032: W/System.err(336): at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1324)
03-11 07:14:33.032: W/System.err(336): at healthy.com.sdp.db.DataBaseHelper.executeRawQuery(DataBaseHelper.java:149)
03-11 07:14:33.032: W/System.err(336): at healthy.com.sdp.activity.StateListActivity.onCreate(StateListActivity.java:58)
03-11 07:14:33.032: W/System.err(336): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
03-11 07:14:33.032: W/System.err(336): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
03-11 07:14:33.032: W/System.err(336): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
03-11 07:14:33.032: W/System.err(336): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
03-11 07:14:33.050: W/System.err(336): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
03-11 07:14:33.050: W/System.err(336): at android.os.Handler.dispatchMessage(Handler.java:99)
03-11 07:14:33.052: W/System.err(336): at android.os.Looper.loop(Looper.java:123)
03-11 07:14:33.052: W/System.err(336): at android.app.ActivityThread.main(ActivityThread.java:3683)
03-11 07:14:33.052: W/System.err(336): at java.lang.reflect.Method.invokeNative(Native Method)
03-11 07:14:33.052: W/System.err(336): at java.lang.reflect.Method.invoke(Method.java:507)
03-11 07:14:33.052: W/System.err(336): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
03-11 07:14:33.052: W/System.err(336): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
03-11 07:14:33.052: W/System.err(336): at dalvik.system.NativeStart.main(Native Method)
03-11 07:14:33.052: D/AndroidRuntime(336): Shutting down VM
03-11 07:14:33.052: W/dalvikvm(336): threadid=1: thread exiting with uncaught exception (group=0x40015560)
03-11 07:14:33.072: E/AndroidRuntime(336): FATAL EXCEPTION: main
03-11 07:14:33.072: E/AndroidRuntime(336): java.lang.RuntimeException: Unable to start activity ComponentInfo{healthy.com.sdp/healthy.com.sdp.activity.StateListActivity}: java.lang.NullPointerException
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.os.Handler.dispatchMessage(Handler.java:99)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.os.Looper.loop(Looper.java:123)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.ActivityThread.main(ActivityThread.java:3683)
03-11 07:14:33.072: E/AndroidRuntime(336): at java.lang.reflect.Method.invokeNative(Native Method)
03-11 07:14:33.072: E/AndroidRuntime(336): at java.lang.reflect.Method.invoke(Method.java:507)
03-11 07:14:33.072: E/AndroidRuntime(336): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
03-11 07:14:33.072: E/AndroidRuntime(336): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
03-11 07:14:33.072: E/AndroidRuntime(336): at dalvik.system.NativeStart.main(Native Method)
03-11 07:14:33.072: E/AndroidRuntime(336): Caused by: java.lang.NullPointerException
03-11 07:14:33.072: E/AndroidRuntime(336): at healthy.com.sdp.activity.StateListActivity.onCreate(StateListActivity.java:61)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
03-11 07:14:33.072: E/AndroidRuntime(336): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
03-11 07:14:33.072: E/AndroidRuntime(336): ... 11 more
03-11 07:14:37.442: I/Process(336): Sending signal. PID: 336 SIG: 9
感谢您的帮助。
答案 0 :(得分：0)