如何使用ActiveAndroid从预填充的数据库检索数据?
我已经尝试在我的项目上实现ActiveAndroid来读取我资产文件夹中的现有数据库。我已经执行了query方法并将其放入arraylist中,但它不起作用。请查看我的代码 MainActivity.java:如何使用ActiveAndroid从预填充的数据库检索数据?,android,sqlite,activeandroid,Android,Sqlite,Activeandroid,我已经尝试在我的项目上实现ActiveAndroid来读取我资产文件夹中的现有数据库。我已经执行了query方法并将其放入arraylist中,但它不起作用。请查看我的代码 MainActivity.java: public class MainActivity extends AppCompatActivity { //Array list for storing all the inventoryItems private ArrayList<String> questionI
public class MainActivity extends AppCompatActivity {
//Array list for storing all the inventoryItems
private ArrayList<String> questionItems;
//Adapter for listview
private ArrayAdapter questionItemsAdapter;
private ListView listViewQuestion;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ActiveAndroid.initialize(this);
listViewQuestion = (ListView) findViewById(R.id.listViewQuestion);
//Initializing arraylist
questionItems = new ArrayList<>();
showList();
}
public static List<Questions> getAll() {
return new Select()
.from(Questions.class)
.orderBy("question ASC")
.execute();
}
private void showList() {
//Creating a list and getting all questions from the method
List<Questions> questions = getAll();
//Adding all the items of the questions to arraylist
for (int i = 0; i < questions.size(); i++) {
Questions question = questions.get(i);
questionItems.add(question.question);
}
//Creating our adapter
questionItemsAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, questionItems);
//Adding adapter to listview
listViewQuestion.setAdapter(questionItemsAdapter);
}
}
结果显示只有一个空白。我哪里做错了?
我已经使用其他方法在这个预填充数据库上工作了将近2个月,但我没有找到我需要的方法。您仍然在使用ListView@Ewo@LutaayaHuzaifahIdris请你详细说明一下好吗?现在我们使用的是RecyclerViews而不是ListViews@LutaayaHuzaifahIdris好,实际上,列表视图只是为了测试我的应用程序是否可以读取预填充的数据库。以后如果证明数据库可以读取,我就不再使用它了。但我想我还是需要把数据放到ArrayList里,不是吗?你怎么认为?
@Table(name = "Questions")
public class Questions extends Model {
@Column (name = "question")
public String question;
@Column (name = "answer")
public String answer;
public Questions(){
super();
}
public Questions(String question, String answer){
super();
this.question = question;
this.answer = answer;
}
}