问题描述
//第一个case R.id.selectId:
mmanager=(NotificationManager)this.getSystemService(NOTIFICATION_SERVICE);Intent intent=new Intent(this, AllSchool.class);PendingIntent pending=PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);Notification notification=new Notification.Builder(this).setAutoCancel(true).setTicker('下拉查看').setSmallIcon(R.drawable.ic_launcher).setContentTitle('学校').setContentText('详细信息').setContentIntent(pending).build();mmanager.notify(1,notification);break;
//第二个protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.manager);listViewId=(ListView)findViewById(R.id.listViewId); adapter=new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,contactList); listViewId.setAdapter(adapter); readManager(); }public void readManager(){ SQLiteDatabase db2=msh.getWritableDatabase(); Cursor cursor=db2.query('school', null, null, null, null, null, null);if(cursor.moveToFirst()) {int id=cursor.getInt(cursor.getColumnIndex('id'));int phone=cursor.getInt(cursor.getColumnIndex('phone'));String name=cursor.getString(cursor.getColumnIndex('name'));String address=cursor.getString(cursor.getColumnIndex('address'));//Log.d('MainActivity','id is'+id);//Log.d('MainActivity','phone is'+phone);//Log.d('MainActivity','name is'+name);//Log.d('MainActivity','address is'+address);contactList.add(id+'n'+phone+'n'+name+'n'+address); }
错误提示 空指针异常
问题解答
回答1：首先确保你的数据库中有’school’这个表，然后确定这个表有’id’’phone’’name’’address’的字段，接着确定表中有数据，代码中可以在获取到cursor后判断是否为null，打个Log看一下。
