Android 由于java.lang.IllegalArgumentException:column'_id';不存在
每当我启动我的应用程序时,我都会得到一个Android 由于java.lang.IllegalArgumentException:column'_id';不存在,android,sqlite,crash,cursor,Android,Sqlite,Crash,Cursor,每当我启动我的应用程序时,我都会得到一个java.lang.IllegalArgumentException:列'\u id'在我的日志中不存在错误。我已经创建了列“\u id”,但它仍然抛出这个。以下是我的主要.java: package com.gantt.shoppinglist; import android.app.Dialog; import android.app.ListActivity; import android.database.Cursor; import andro
java.lang.IllegalArgumentException:列'\u id'在我的日志中不存在
错误。我已经创建了列“\u id”
,但它仍然抛出这个。以下是我的主要.java:
package com.gantt.shoppinglist;
import android.app.Dialog;
import android.app.ListActivity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class ShoppingList extends ListActivity {
private DataHelper DataHelper;
/** Called when the activity is first created. */
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DataHelper = new DataHelper(this);
Cursor c = (Cursor) DataHelper.selectAll();
long id = c.getLong(c.getColumnIndex("_id"));
startManagingCursor(c);
ListView lv = (ListView) findViewById(android.R.id.list);
String[] from = new String[] { com.gantt.shoppinglist.DataHelper.getDatabaseName() };
int[] to = new int[] { android.R.id.text1 };
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,
android.R.layout.simple_list_item_1, c, from, to);
lv.setAdapter(adapter);
Button button1main = (Button) findViewById(R.id.add);
button1main.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
final Dialog additem = new Dialog(ShoppingList.this);
additem.setContentView(R.layout.maindialog);
final EditText et = (EditText)additem.findViewById(R.id.edittext);
additem.setTitle("Type your item");
additem.setCancelable(true);
et.setHint("Type the name of an item...");
Button button = (Button) additem.findViewById(R.id.cancel);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
additem.dismiss();
}
});
additem.show();
Button ok = (Button) additem.findViewById(R.id.ok);
ok.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
final String text = et.getText().toString();
additem.dismiss();
et.setText("");
}
});
}
});
}
}
以下是我的DataHelper类:
package com.gantt.shoppinglist;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteStatement;
import android.util.Log;
public class DataHelper {
private static final String DATABASE_NAME = "items.db";
private static final int DATABASE_VERSION = 1;
private static final String TABLE_NAME = "table1";
public static final String KEY_ROWID = "_id";
private Context context;
private SQLiteDatabase db;
private SQLiteStatement insertStmt;
private static final String INSERT = "insert into "
+ TABLE_NAME + "(name) values (?)";
public DataHelper(Context context) {
this.context = context;
OpenHelper openHelper = new OpenHelper(this.context);
this.db = openHelper.getWritableDatabase();
this.insertStmt = this.db.compileStatement(INSERT);
}
public long insert(String name) {
this.insertStmt.bindString(1, name);
return this.insertStmt.executeInsert();
}
public void deleteAll() {
this.db.delete(TABLE_NAME, null, null);
}
public Cursor selectAll() {
List<String> list = new ArrayList<String>();
Cursor cursor = this.db.query(TABLE_NAME, new String[] { "name" },
null, null, null, null, "name desc");
if (cursor.moveToFirst()) {
do {
list.add(cursor.getString(0));
} while (cursor.moveToNext());
}
if (cursor != null && !cursor.isClosed()) {
cursor.close();
}
return cursor;
}
public static String getDatabaseName() {
return DATABASE_NAME;
}
private static class OpenHelper extends SQLiteOpenHelper {
OpenHelper(Context context) {
super(context, getDatabaseName(), null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "(id INTEGER PRIMARY KEY, name TEXT");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w("Example", "Upgrading database, this will drop tables and recreate.");
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
}
}
package com.gantt.shoppinglist;
导入java.util.ArrayList;
导入java.util.List;
导入android.content.Context;
导入android.database.Cursor;
导入android.database.sqlite.SQLiteDatabase;
导入android.database.sqlite.SQLiteOpenHelper;
导入android.database.sqlite.SQLiteStatement;
导入android.util.Log;
公共类DataHelper{
私有静态最终字符串数据库\u NAME=“items.db”;
私有静态最终int数据库_VERSION=1;
私有静态最终字符串表\u NAME=“table1”;
公共静态最终字符串键_ROWID=“_id”;
私人语境;
专用数据库数据库;
私有SQLiteStatement insertStmt;
私有静态最终字符串INSERT=“插入到”
+表_NAME+“(NAME)值(?);
公共DataHelper(上下文){
this.context=上下文;
OpenHelper OpenHelper=新的OpenHelper(this.context);
this.db=openHelper.getWritableDatabase();
this.insertStmt=this.db.compileStatement(INSERT);
}
公共长插入(字符串名称){
this.insertStmt.bindString(1,名称);
返回此.insertStmt.executeInsert();
}
public void deleteAll(){
this.db.delete(表名称,null,null);
}
公共游标selectAll(){
列表=新的ArrayList();
Cursor Cursor=this.db.query(表名,新字符串[]{“NAME”},
空,空,空,空,“名称描述”);
if(cursor.moveToFirst()){
做{
list.add(cursor.getString(0));
}while(cursor.moveToNext());
}
if(cursor!=null&!cursor.isClosed()){
cursor.close();
}
返回光标;
}
公共静态字符串getDatabaseName(){
返回数据库名称;
}
私有静态类OpenHelper扩展了SQLiteOpenHelper{
OpenHelper(上下文){
super(上下文,getDatabaseName(),null,数据库版本);
}
@凌驾
public void onCreate(SQLiteDatabase db){
db.execSQL(“创建表”+表名称+”(id整数主键,名称文本”);
}
@凌驾
public void onUpgrade(SQLiteDatabase db,int-oldVersion,int-newVersion){
w(“示例”,“升级数据库,这将删除表并重新创建”);
db.execSQL(“如果存在删除表”+表名称);
onCreate(db);
}
}
}
嗯,不确定是否粘贴错误,但:
DataHelper = new DataHelper(this);
Cursor c = (Cursor) DataHelper.selectAll();
错误。您需要将其声明给一个对象,并对初始化的数据库对象调用您的方法:
DataHelper dataHelper = new DataHelper(this);
Cursor c = (Cursor) dataHelper.selectAll();
哦,糟糕,您刚刚用大写字母D声明了变量名,这不是推荐的,也不是标准的java编码风格
我有一个类似的问题-我认为这是一个必须“选择”(或“选择为”)一个称为
\u id
的东西的情况,因为SimpleCursorAdapter
需要它
从:
处理内容URI ID
按照惯例,提供程序通过以下方式提供对表中单个行的访问:
接受一个内容URI,该URI在
按照惯例,提供者将ID值与表的
\u ID
列,并对匹配的行执行请求的访问
此约定促进了应用程序访问的通用设计模式
提供商。应用程序对提供商进行查询并显示
使用光标或适配器在列表视图中生成光标
。定义
ofCursorAdapter
要求光标中的一列为\u ID
在我的例子中,我的表中有一个名为“oid”的自动编号列,因此我将SELECT命令改为(例如)
这为我解决了这个问题
编辑以显示更广泛的代码
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.channel_selector);
GridView channel_selector_grid = (GridView) findViewById(R.id.channel_grid);
sca = getGuideAdapter();
channel_selector_grid.setAdapter(sca);
}
public SimpleCursorAdapter getGuideAdapter() {
SimpleCursorAdapter adapter = null;
SQLiteDatabase db = SQLiteDatabaseHelper.getReadableDatabase();
Cursor cursor = db.rawQuery("SELECT DISTINCT oid as _id, name, number FROM CHAN_TABLE ORDER BY number", null);
if (cursor.moveToFirst()) {
String[] columnNames = { "name" };
int[] resIds = { R.id.channel_name };
adapter = new SimpleCursorAdapter(this, R.layout.channel_selector_item, cursor, columnNames, resIds);
}
return adapter;
}
您是否确保卸载并重新安装该应用程序,以便您的数据库具有新创建的_id列?或者可能将其包含在升级方法中?类似地,如果使用managedQuery,则必须在字符串[]中包含“_id”数组第二个参数。请注意!我在调用日志中遇到了相同的错误,必须在字段中添加android.provider.CallLog.Calls.\u ID!有效。@Squonk有没有办法更改用于UID的适配器列?@Squonk回答是正确的,与缺少“\u ID”列有关。值得注意的是,\u ID列名的大小写很重要,应该降低ase(至少我发现了)
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.channel_selector);
GridView channel_selector_grid = (GridView) findViewById(R.id.channel_grid);
sca = getGuideAdapter();
channel_selector_grid.setAdapter(sca);
}
public SimpleCursorAdapter getGuideAdapter() {
SimpleCursorAdapter adapter = null;
SQLiteDatabase db = SQLiteDatabaseHelper.getReadableDatabase();
Cursor cursor = db.rawQuery("SELECT DISTINCT oid as _id, name, number FROM CHAN_TABLE ORDER BY number", null);
if (cursor.moveToFirst()) {
String[] columnNames = { "name" };
int[] resIds = { R.id.channel_name };
adapter = new SimpleCursorAdapter(this, R.layout.channel_selector_item, cursor, columnNames, resIds);
}
return adapter;
}