我在按钮的单击事件上创建数据库，当我在下一个触发选择查询时，Activity两个相同的记录显示在ListView. 看不懂怎么回事？？请给我建议。我有以下代码：
ListActivity.java
package com.example.timerdemo2;
import java.util.ArrayList;
import android.R.menu;
import android.os.Bundle;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.view.ContextMenu;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;
import android.widget.AdapterView.AdapterContextMenuInfo;
public class ListActivity extends Activity {
ListView lv;
ArrayList<String> items = new ArrayList<String>();
ArrayList<String> items_id = new ArrayList<String>();
dbhelper dh;
SQLiteDatabase db;
int index_id;
Button btn;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list);
Button btn;
btn = (Button)findViewById(R.id.newProjectlist);
btn.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent= new Intent(ListActivity.this,NewProject.class);
startActivity(intent);
}
});
lv = (ListView)findViewById(R.id.projectListView);
setUpList();
dh = new dbhelper(this);
Cursor c = getAllData();
showAllData(c);
registerForContextMenu(lv);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
// TODO Auto-generated method stub
super.onCreateContextMenu(menu, v, menuInfo);
if(v.getId() == R.id.projectList){
menu.setHeaderIcon(R.drawable.ic_launcher);
menu.setHeaderTitle("Record List");
menu.add(0,1,menu.NONE,"Delete Record");
menu.add(0,2,menu.NONE,"Show Record");
}
}
@Override
public boolean onContextItemSelected(MenuItem item) {
// TODO Auto-generated method stub
int itemId = item.getItemId();
if(itemId == 1)
{
AdapterView.AdapterContextMenuInfo menuinfo = (AdapterContextMenuInfo) item.getMenuInfo();
int poistion = menuinfo.position;
String id_string = items_id.get(poistion);
long id = Long.valueOf(id_string);
//menuinfo = (AdapterContextMenuInfo) item.getMenuInfo();
//index_id = menuinfo.position;
deleteUserData(index_id);
items_id.remove(poistion);
}
if(itemId == 2){
AdapterView.AdapterContextMenuInfo menuinfo;
menuinfo = (AdapterContextMenuInfo) item.getMenuInfo();
index_id = menuinfo.position;
editUserData(index_id);
}
return super.onContextItemSelected(item);
}
private void editUserData(int indexid) {
// TODO Auto-generated method stub
String user_id = items_id.get(indexid);
Intent intEdit = new Intent(ListActivity.this, MainActivity.class);
intEdit.putExtra("EditID", user_id);
startActivityForResult(intEdit, 1);
}
private void deleteUserData(int indexid) {
// TODO Auto-generated method stub
// String user_id = items_id.get(indexid);
//Toast.makeText(getApplicationContext(), "id " + user_id, 1).show();
db = dh.getWritableDatabase();
db.delete("timer","_ID" + "=" + indexid, null);
finish();
// Toast.makeText(getApplicationContext(), "Record deleted successfully", 1).show();
}
private void showAllData(Cursor c) {
// TODO Auto-generated method stub
while(c.moveToNext())
{
int id = c.getInt(0);
String name = c.getString(1);
String timerpoint1 = c.getString(2);
String timerpoint2 = c.getString(3);
String timerpoint3 = c.getString(4);
String servicetime1 = c.getString(5);
String servicetime2 = c.getString(6);
items.add("" + name);
items_id.add(""+id);
}
setUpList();
}
private Cursor getAllData() {
// TODO Auto-generated method stub
db = dh.getReadableDatabase();
//String sortorder = dh.Name + "DESC";
// String query ="SELECT DISTINCT name FROM timer";
// Cursor c = db.rawQuery(query, null);
// if (c != null) {
// c.moveToFirst();
// }
// String[] cols = new String[] {dh.Name, "name"};
Cursor c = db.query(true, "timer",null,null,null,null,null,null, null);
//Cursor cur = db.query(Distinct,"timer", null, null, null, null, null, null, null);
startManagingCursor(c);
return c;
}
private void setUpList() {
// TODO Auto-generated method stub
lv.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,items));
}
}
当显示记录时，ListView两个条目就完成了。我想让记录与众不同。所以提供帮助。
日志猫
01-01 18:42:49.941: W/dalvikvm(12683): threadid=1: thread exiting with uncaught exception (group=0x40015560)
01-01 18:42:49.951: E/AndroidRuntime(12683): FATAL EXCEPTION: main
01-01 18:42:49.951: E/AndroidRuntime(12683): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.timerdemo2/com.example.timerdemo2.ListActivity}: java.lang.IllegalStateException: get field slot from row 0 col 2 failed
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.os.Handler.dispatchMessage(Handler.java:99)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.os.Looper.loop(Looper.java:130)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.ActivityThread.main(ActivityThread.java:3683)
01-01 18:42:49.951: E/AndroidRuntime(12683): at java.lang.reflect.Method.invokeNative(Native Method)
01-01 18:42:49.951: E/AndroidRuntime(12683): at java.lang.reflect.Method.invoke(Method.java:507)
01-01 18:42:49.951: E/AndroidRuntime(12683): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
01-01 18:42:49.951: E/AndroidRuntime(12683): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
01-01 18:42:49.951: E/AndroidRuntime(12683): at dalvik.system.NativeStart.main(Native Method)
01-01 18:42:49.951: E/AndroidRuntime(12683): Caused by: java.lang.IllegalStateException: get field slot from row 0 col 2 failed
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.database.CursorWindow.getString_native(Native Method)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.database.CursorWindow.getString(CursorWindow.java:329)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:49)
01-01 18:42:49.951: E/AndroidRuntime(12683): at com.example.timerdemo2.ListActivity.showAllData(ListActivity.java:123)
01-01 18:42:49.951: E/AndroidRuntime(12683): at com.example.timerdemo2.ListActivity.onCreate(ListActivity.java:56)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-01 18:42:49.951: E/AndroidRuntime(12683): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
01-01 18:42:49.951: E/AndroidRuntime(12683): ... 11 more
01-01 18:42:52.430: D/dalvikvm(12758): GC_EXTERNAL_ALLOC freed 53K, 50% free 2739K/5379K, external 716K/1038K, paused 112ms