在我的应用程序中，我想使用 CustomAdapter 类创建 SpinnerList，为此我写了下面的代码，但是当我点击微调器列表时，数组列表图像没有加载到微调器列表中，就像我下面的屏幕一样，为什么会出现这个问题 future ？

main_layout.xml:-

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dip"
        android:text="Category:"
        android:layout_marginBottom="5dp"/>

    <Spinner
        android:id="@+id/spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>

</LinearLayout>

MainActivity:-

public class MainActivity extends AppCompatActivity  {

    public static final String[] titles = new String[] { "Strawberry",
            "Banana", "Orange", "Hello" };

    public static final Integer[] images = { R.drawable.image1,
            R.drawable.image2, R.drawable.image3, R.drawable.image4 };

    Spinner spinner;
    List<RowItem> rowItems;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_layout);

        rowItems = new ArrayList<RowItem>();
        for (int i = 0; i < titles.length; i++) {

            RowItem item = new RowItem(titles[i],images[i]);
            rowItems.add(item);
        }

        spinner = (Spinner)findViewById(R.id.spinner);
       CustomAdapter adapter = new CustomAdapter(MainActivity.this,
            R.layout.listitems_layout, R.id.title, rowItems);
        spinner.setAdapter(adapter);
    }
}

listitems_layout.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="match_parent"
    android:orientation="horizontal">

    <ImageView
        android:id="@+id/icon"
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:src="@drawable/image1"
        android:padding="10dp"
        />

    <TextView
        android:layout_marginTop="30dp"
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@+id/icon"
        android:textColor="#CC0033"
        android:text="Strawberry"
        android:textSize="16dp" />

</LinearLayout>

自定义适配器:-

package com.example.venkat.spinnerexample1;


import android.app.Activity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.view.LayoutInflater;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.List;

public class CustomAdapter extends ArrayAdapter<RowItem> {

    LayoutInflater flater;

     public CustomAdapter(Activity context,int resouceId, int textviewId, List<RowItem> list){

    super(context,resouceId,textviewId, list);
    flater = context.getLayoutInflater();
}

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        RowItem rowItem = getItem(position);

        View rowview = flater.inflate(R.layout.listitems_layout,null,true);

        TextView txtTitle = (TextView) rowview.findViewById(R.id.title);
        txtTitle.setText(rowItem.getTitle());

        ImageView imageView = (ImageView) rowview.findViewById(R.id.icon);
        imageView.setImageResource(rowItem.getImageId());

        return rowview;
    }
}

行项目:-

package com.example.venkat.spinnerexample1;

public class RowItem {

    private int ImageId;
    private String Title;

    public RowItem(String Title,int ImageId){

        this.Title = Title;
        this.ImageId = ImageId;
    }

    public String getTitle(){

        return Title;
    }

    public void setTitle(String Title){

        this.Title = Title;
    }

    public int getImageId(){

        return ImageId;
    }

    public void setImageId(int ImageId){

        this.ImageId = ImageId;
    }

    @Override
    public String toString() {
        return Title ;
    }
}

屏幕:- ---

最佳答案

像这样改变你的适配器

public class CustomAdapter extends ArrayAdapter<RowItem> {

    LayoutInflater flater;

    public CustomAdapter(Activity context, int resouceId, int textviewId, List<RowItem> list){

        super(context,resouceId,textviewId, list);
//        flater = context.getLayoutInflater();
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        return rowview(convertView,position);
    }

    @Override
    public View getDropDownView(int position, View convertView, ViewGroup parent) {
        return rowview(convertView,position);
    }

    private View rowview(View convertView , int position){

        RowItem rowItem = getItem(position);

        viewHolder holder ;
        View rowview = convertView;
        if (rowview==null) {

            holder = new viewHolder();
            flater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            rowview = flater.inflate(R.layout.listitems_layout, null, false);

            holder.txtTitle = (TextView) rowview.findViewById(R.id.title);
            holder.imageView = (ImageView) rowview.findViewById(R.id.icon);
            rowview.setTag(holder);
        }else{
            holder = (viewHolder) rowview.getTag();
        }
        holder.imageView.setImageResource(rowItem.getImageId());
        holder.txtTitle.setText(rowItem.getTitle());

        return rowview;
    }

    private class viewHolder{
        TextView txtTitle;
        ImageView imageView;
    }
}

关于android - 如何在 android 中使用自定义适配器创建 Spinner-list，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/35983176/