我在尝试从SQLite读取数据时遇到问题,我想将所有信息存储到已定义的对象(节点)数组中。获取所有行SQLite Android Studio
我的构造和结构,其目标是:
public node(int id, String name, String address, double x, double y, String type, String date){
//Initialization
//....
}
注:此对象的类显然已经定义的属性,setter和getter方法。数据库与该对象具有相同的结构(Int,String,String,Double,Double,String,String)。
所以,我的方法来获取所有的行,并将它们存储到我的数组:
public nodo[] getNodes() {
String selectQuery = "SELECT * FROM " + NAME_NODES;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
node[] nodes = new node[cursor.getCount()];
int con = 0;
if (cursor.moveToFirst()) {
while (cursor.moveToNext()) {
node temp = new node(
cursor.getInt(1),
cursor.getString(2),
cursor.getString(3),
cursor.getDouble(4),
cursor.getDouble(5),
cursor.getString(6),
cursor.getString(7));
nodes[con++] = temp;
}
}
cursor.close();
db.close();
Log.d(TAG, "SQLite data: " + nodes.toString());
return nodes;
}
然后在其他类我把这个以前的方法,是这样的:
node[] nodes = db.getNodes();
String temp = node[0].getName();
但经过我得到一个错误:
<code>E/CursorWindow: Failed to read row 1, column 7 from a CursorWindow which has 2 rows, 7 columns.
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.motusk.AppMonitoreo, PID: 4410
java.lang.IllegalStateException: Couldn't read row 1, col 7 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
at android.database.CursorWindow.nativeGetString(Native Method)
at android.database.CursorWindow.getString(CursorWindow.java:438)
at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51)
at com.motus.AppMonitoreo.Controladores.SQLiteHandler.getNodes(SQLiteHandler.java:186)</code>
我觉得主要的问题是在使用游标
请你在光标光标= db.rawQuery(selectQuery,NULL)获得;光标?光标索引从0开始,并从1开始。请检查 –
[单击此处。我希望这会帮助你](http://stackoverflow.com/a/41615670/7399521) –
是的,是coursor索引从0开始,但现在我只得到1行 –