本文介绍了NullPointerException异常上getWritableDatabase()的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我对getWritableDatabase问题NullPointerException异常()
i have a problem NullPointerException on getWritableDatabase()
public class DatabaseTable extends Activity {
private Context context;
@Override
public void onCreate(Bundle savedInstanceState) {
LBD conection = LBD.get(this);
super.onCreate(savedInstanceState);
}
}
有是一个实现不起作用openHelper.getWritableDatabase()
There is an implementation does not work "openHelper.getWritableDatabase()"
public class LBD {
private Context context;
private static SQLiteDatabase db;
private OpenHelper openHelper;
public static LBD get(Context context) {
LBD lbd = new LBD(context);
lbd.open();
return lbd;
}
public LBD(Context c) {
context = c;
}
final public void open() {
openHelper = new OpenHelper(context);
db = openHelper.getWritableDatabase();
}
public class OpenHelper extends SQLiteOpenHelper {
OpenHelper(Context context) {
super(context, "rss_base.db", null, 3);
}
}
}
我意识到,我忘了初始化的onCreate感谢大家
推荐答案
最有可能你的上下文
openHelper = new OpenHelper(context);
为空。请确保您的上下文
设置。但我建议你提供更多的细节,在这里添加您的logcat的。
is null. Make sure that your Context
is set. But i recommend to you provide more details, add here your logcat.
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