android - 非法状态异常 : get field slot from row 0 col -1 failed

Question

int columnIndexFromAddrCountry;

public FavoritesActAdapter(Context context, int layout, 
        Cursor c, String[] from, int[] to) {
    super(context, layout, c, from, to);
    gnCursor = c;

    columnIndexFromAddrCountry = 
        c.getColumnIndex(DBAdapter.KEY_FROM_ADDR_COUNTRY);

}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    gnCursor = getCursor();

    final String fromAddrCountry = 
        gnCursor.getString(columnIndexFromAddrCountry);

        ...

        super.bindView(view, context, cursor);
}

为什么我会收到 IllegalStateException？

IllegalStateException: get field slot from row 0 col -1 failed

这个异常是什么意思？此行抛出异常

final String fromAddrCountry = gnCursor.getString(columnIndexFromAddrCountry);

因为 columnIndexFromAddrCountry 是 -1。该列存在，并且可以解析其他十个列。什么会导致这个问题？

提前致谢!

Answer 1

DBAdapter.KEY_FROM_ADDR_COUNTRY 设置为什么？

来自Cursor doc

public abstract int getColumnIndex (String columnName)

Since: API Level 1 Returns the zero-based index for the given column name, or -1 if the column doesn't exist. If you expect the column to exist use getColumnIndexOrThrow(String) instead, which will make the error more clear

因此您可以使用 getColumnIndexOrThrow(String) 获得更好的错误消息以帮助您进行调试。