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java如何编写ArrayList适配器?

我想将arrayList的字段添加到listView,但我不知道如何编写适配器。请帮帮我

我需要一个适配器类。我必须在listView上查看tutar:1.34 kalem=“xx”

类别:

public class Income {





String kalem;
int tutar;

public int getTutar() {
    return tutar;
}
public void setTutar(int tutar) {
    this.tutar = tutar;
}
int id;
public int getId() {
    return id;
}
public void setId(int id) {
    this.id = id;
}

public String getKalem() {
    return kalem;
}
public void setKalem(String kalem) {
    this.kalem = kalem;
}

}

ArrayList:

sqliteHelper helper = new sqliteHelper(getApplicationContext());
    ArrayList<Income> liste=helper.getAllIncome();

共 (2) 个答案

  1. # 1 楼答案

    有两种方法可以构建适配器:

  2. 使用Android系统提供的一些适配器,如:-
     SimpleCursorAdapter
     ArrayAdapter,etc
    

    示例:

     ListView listView = (ListView) findViewById(R.id.<list_view_id>);
     ArrayList<Income> income_array_list = <get the arraylist from whatever sources>;
     ArrayAdapter<Income> arrayAdapter = new ArrayAdapter<Income>(
             this, 
             android.R.layout.simple_list_item_1,
             income_array_list );
    
     listView.setAdapter(arrayAdapter); 
    
    创建您自己的自定义适配器

    我只使用了两个字段来演示如何构建自定义适配器,其余部分可以通过查看以下代码来构建

    示例:-

    IncomeListAdapter类

    private class IncomeListAdapter extends BaseAdapter {
    
        ArrayList<Income> mDisplayedValues;
        LayoutInflater inflater;
    
        public IncomeListAdapter(Context context) {
            // TODO Auto-generated constructor stub
            mDisplayedValues = <your_Income_list>;
            inflater = (LayoutInflater) context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        }
    
        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return mDisplayedValues.size();
        }
    
        @Override
        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return null;
        }
    
        @Override
        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return 0;
        }
    
        @Override
        public View getView(final int position, View convertView,
                ViewGroup parent) {
            // TODO Auto-generated method stub
    
            View v = convertView;
            ViewHolder holder;
            if (v == null) {
                v = inflater.inflate(R.layout.listrow_income, null);
                holder = new ViewHolder();
                holder.tvTutar = (TextView) v
                        .findViewById(R.id.tvTutar);
                holder.tvId = (TextView) v.findViewById(R.id.tvId);
    
                v.setTag(holder);
            } else
                holder = (ViewHolder) v.getTag();
                   holder.tvTutar.setText(mDisplayedValues.get(position).getTutar());
               holder.tvId.setText(mDisplayedValues.get(position).getId());
               return v;
        }
    
        class ViewHolder {
            TextView tvTutar;
            TextView tvId;
        }
    }
    

    列出收入。xml:

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="?android:attr/listPreferredItemHeight"
    android:gravity="center"
    android:orientation="horizontal"
    android:padding="8dp" >
       <TextView
        android:id="@+id/tvTutar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#323232" />
       <TextView
        android:id="@+id/tvId"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@android:color/white"    />
    
     </LinearLayout>
    
  3. # 2 楼答案

    试试这个

    private ListView lv;
    
    public void onCreate(Bundle saveInstanceState) {
         setContentView(R.layout.your_layout);
    
         lv = (ListView) findViewById(R.id.your_list_view_id);
    
         // Instanciating an array list (you don't need to do this, 
         // you already have yours).
         sqliteHelper helper = new sqliteHelper(getApplicationContext());
         ArrayList<Income> your_array_list = helper.getAllIncome();
    
         // This is the array adapter, it takes the context of the activity as a 
         // first parameter, the type of list view as a second parameter and your 
         // array as a third parameter.
         ArrayAdapter<Income> arrayAdapter = new ArrayAdapter<Income>(
                 this, 
                 android.R.layout.simple_list_item_1,
                 your_array_list );
    
         lv.setAdapter(arrayAdapter); 
    }