Question

我有一个提醒应用，我想要显示不同的节目时间表。我有四个部分

概述（所有时间表的详细信息）
今天
明天

10天以后

现在我可以列出＆＃39;概述＆＃39;在cursoradapter的帮助下。但我今天不能列出＆＃39;其余部分 - 屏幕保持空白。这是我的todayActivity

代码

在oncreate（）---

中

    DatabaseHelper fdb = new DatabaseHelper(this);
    db = fdb.getReadableDatabase();
    cursor = db.rawQuery("select * from "+TABLE_NAME+" where "+COLUMN_DAY+" = "+day+" and "+
            COLUMN_MONTH+" = "+month+" and "+COLUMN_YEAR+" = "+year+";",null);

    adapter = new AppointmentAdapter(this, cursor);
    listView.setAdapter(adapter);

在onresume（）----

        DatabaseHelper fdb = new DatabaseHelper(this);
        SQLiteDatabase db = fdb.getReadableDatabase();
        Cursor newCursor = db.rawQuery("select * from "+TABLE_NAME+" where "+COLUMN_DAY+" = "+day+" and "+
                COLUMN_MONTH+" = "+month+" and "+COLUMN_YEAR+" = "+year+";",null);

        //RecyclerView recyclerView=findViewById(R.id.recycler);
        AppointmentAdapter adapter = (AppointmentAdapter)listView.getAdapter();

        adapter.changeCursor(newCursor);
        cursor = newCursor;

这是我的自定义游标适配器类----

 public void bindView(View view, Context context, Cursor cursor) {

    int drawable = 0;
    ImageView imgView = view.findViewById(R.id.type_image);
    name = cursor.getString(cursor.getColumnIndex(COLUMN_NAME));
    type = cursor.getString(cursor.getColumnIndex(COLUMN_TYPE));
    date = cursor.getString(cursor.getColumnIndex(COLUMN_DAY));
    month = cursor.getString(cursor.getColumnIndex(COLUMN_MONTH));
    year = cursor.getString(cursor.getColumnIndex(COLUMN_YEAR));
    hour = cursor.getString(cursor.getColumnIndex(COLUMN_HOUR));
    minute = cursor.getString(cursor.getColumnIndex(COLUMN_MINUTE));
    phone = cursor.getString(cursor.getColumnIndex(COLUMN_PHONE));

    if (type.equals("Health"))
        drawable = R.drawable.icons8_stethoscope_96;
    else if (type.equals("Personal"))
        drawable = R.drawable.icons8_resume_96;
    else if (type.equals("Work"))
        drawable = R.drawable.icons8_business_80;
    else if (type.equals("School"))
        drawable = R.drawable.icons8_school_80;
    else if (type.equals("Other"))
        drawable = R.drawable.icons8_exclamation_mark_48;

    imgView.setImageResource(drawable);

    TextView textView1 = view.findViewById(R.id.clock_text);
    textView1.setText(hour + ":" + minute);
    TextView textView2 = view.findViewById(R.id.date_text);
    textView2.setText(date + "-" + month + "-" + year);
    TextView textView = view.findViewById(R.id.nameText);
    textView.setText(name);
    TextView textView3 = view.findViewById(R.id.phoneText);
    textView3.setText(phone);
}

所以，我的问题是如何使自定义cursoradapter的光标知道我需要的数据库中的某些条件？这可能会在之前被问到，但我无法找到问题的解决方案。请帮我。在此先感谢!!!

Answer 1

尝试使用db.query（），它具有selection和selectionArgs作为条件选择的参数。

Cursor cursor = db.query(
    TABLE_NAME,   // The table to query
    projection,           // The array of columns to return (pass null to get all)
    selection,            // The columns for the WHERE clause
    selectionArgs,        // The values for the WHERE clause
    null,                 // don't group the rows
    null,                 // don't filter by row groups
    sortOrder             // The sort order
    );

在你的情况下，selction和selectionArgs将是：

 String selection = COLUMN_DAY+ " = ? AND"+COLUMN_MONTH+ " = ? 
 AND"+COLUMN_YEAR+" = ?";

 String[] selectionArgs = { day, month, year };

确保日，月和年是字符串。

如何使用一些条件进行sqlite数据库查询

1 个答案: