从sqlite的收集数据，并在TextView中显示它 [英] Collect data from sqlite and display it in TextView

问题描述

我能提取我感兴趣这样的数据：

I was able to be extracted the data that interest me in this way:

Cursor stipcursor = dataBase.rawQuery("SELECT (riepilogo) AS stip FROM "+DbHelper.RIEPILOGO+" WHERE MESI = 'Gennaio' and ANNI = "+anno+"", null);
                                            int colIndexstip = stipcursor.getColumnIndex("stip");
                                            if (colIndexstip == -1)
                                            return;
                                            else
                                            stipcursor.moveToFirst();
                                            double stip = stipcursor.getDouble(colIndexstip);
                                            System.out.println("Riepilogo"+stip);

问题是，如果数据库中有数据，一切正常，但如果数据库是空的，应用程序崩溃。

the problem is that if the database has data, everything works, but if the database is empty, the application crashes.

推荐答案

由于给出的这后，试试这个

As given in this post, try this

if ( cursor.moveToFirst() ) {
    // start activity a
} else {
    // start activity b
}

cursor.moveToFirst（）将返回false，如果指针是空的。这对我的作品始终。

cursor.moveToFirst() will return false if the cursor is empty. It works for me always.

您可以尝试在该帖子还给出了第一种方法。

You can try the first method given on that post also.

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