Question

这是我在DatabaseHelper

中的查询

public List<String> getallstatus(){
        List<String> list = new ArrayList<>();
        String query  = "select * from ref_status";
        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cursor  = db.rawQuery(query,null);
        try{
            if(cursor.moveToFirst()){

                do{
                    list.add(cursor.getString(0));
                    list.add(cursor.getString(1));

                }while(cursor.moveToNext());

            }

            cursor.close();
            db.close();


        }catch(Exception e){
            Log.e("onins" , e.getMessage(),e);

        }
        return list;
    }

这是我的dataProvider类

public class DataProvider {

    private String regcode, regname;

    public DataProvider(String regcode, String regname){
        this.regcode =regcode;
        this.regname = regname;
    }

    public String getRegcode(){ return regcode;  }

    public void setRegCode(){ this.regcode = regcode; }

    public String getRegname(){ return regname;  }

    public void setRegname() { this.regname = regname; }


    @Override
    public String toString(){
        return regname;
    }
    @Override
    public boolean equals(Object obj) {
        if(obj instanceof DataProvider){
            DataProvider c = (DataProvider ) obj;
            if(c.getRegname().equals(regname) && c.getRegcode()==regcode ) 
              return true;
        }
        return false;
    }

}

这是我主要活动中的onCreate

        db = new DatabaseHelper(getApplicationContext());
        List<String> result = db.getallstatus();

        //spinner elements
        ArrayList<DataProvider> datalist = new ArrayList<>();


        ArrayAdapter<DataProvider> adapter = new ArrayAdapter<DataProvider>(this,android.R.layout.simple_spinner_dropdown_item,datalist);
        // Drop down layout style - list view with radio button
       // adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        //attaching adapter to spinner
        valueofspin.setAdapter(adapter);
       // valueofspin.setSelection(adapter.getPosition(myItem));

我只想将此List结果传递给我的数组适配器。我是android studio的新手，希望有人可以帮助我。提前谢谢。

Answer 1

这样做在Arrayadapter中创建一个构造函数

  public class ArrayAdapter extends....{
  ArrayList<DataProvider> dataList;
  List<String> list;
  ArrayAdapter(Context context,resources id,ArrayList<DataProvider> 
  dataList,List<String> list){
  this.context=context;
  this.dataList = datalist;
  this.list = list
}
}

在您的活动上......执行此操作

    ArrayAdapter<DataProvider> adapter = new ArrayAdapter<DataProvider>(this,android.R.layout.simple_spinner_dropdown_item,datalist,result);

通过构造函数传递结果..

List to Array适配器

1 个答案: