Question

我有基本的expandablelistview，想知道如何让每个孩子和小组都有不同的图像。我是否需要以某种方式修改可扩展列表适配器？任何帮助，想法，评论将不胜感激。谢谢:)）

MainActivity：

    public class MainActivity extends Activity{
           .....
public static final Integer[] images = {
            R.drawable.vegetables,
            R.drawable.fruits,
            R.drawable.drinks,
            R.drawable.dessert

        };

            @Override
            protected void onCreate(Bundle savedInstanceState) {


        }

}

我的适配器

public class ExpandableListAdapter extends BaseExpandableListAdapter{


    @Override
    public View getChildView(int groupPosition,final int childPosition, boolean isLastChild, View convertView,
            ViewGroup parent) {

         final String childText = (String) getChild(groupPosition, childPosition);

          if (convertView == null) {
                LayoutInflater infalInflater = (LayoutInflater) this._context
                        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = infalInflater.inflate(R.layout.list_item, null);
            }
          TextView txtListChild = (TextView) convertView
                    .findViewById(R.id.lblListItem);
          txtListChild.setText(childText);

          ImageView imgListChild= (ImageView) convertView
                  .findViewById(R.id.IV_childImage);

// I could store images somehow in two dimensional array and then depending on that draw their reference id.
//          imgListChild.setImageResource();

        return convertView;
    }


    @Override
    public View getGroupView(int groupPosition, boolean isExpanded,
            View convertView, ViewGroup parent) {


         String headerTitle = (String) getGroup(groupPosition);
            if (convertView == null) {
                LayoutInflater infalInflater = (LayoutInflater) this._context
                        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = infalInflater.inflate(R.layout.list_group, null);
            }

            TextView lblListHeader = (TextView) convertView
                    .findViewById(R.id.lblListHeader);
            lblListHeader.setTypeface(null, Typeface.BOLD);
            lblListHeader.setText(headerTitle);
            ImageView imgListGroup= (ImageView) convertView
                    .findViewById(R.id.IV_group);

            imgListGroup.setImageResource(MainActivity.images[groupPosition]);

            return convertView;
    }

    @Override
    public boolean hasStableIds() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        // TODO Auto-generated method stub
        return true;
    }










}

Answer 1

在ImageView和list_group xml文件中添加list_item，并将图片设置为适配器类中的ImageView。

就像您将文字设置为TextView一样，您可以将图像设置为ImageView

TextView txtListChild = (TextView) convertView
                    .findViewById(R.id.lblListItem);
          txtListChild.setText(childText);
ImageView imgListChild = (ImageView) convertView
                    .findViewById(R.id.image);

            imgListChild.setImageResource(R.drawable.imagename);

并且您的xml文件应该是

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="horizontal" >

<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/lblListHeader"
    android:layout_width="wrap_content"
    android:layout_height="?android:attr/listPreferredItemHeight"
    android:layout_marginLeft="8dp"
    android:drawableRight="@drawable/ic_launcher"
    android:gravity="center_horizontal"
    android:paddingLeft="32dp"
    android:paddingTop="8dp"
    android:text="Test"
    android:textSize="20sp"
    android:textAlignment="textEnd"
    android:textStyle="bold" >


</CheckedTextView> 

    <ImageView 
    android:id="@+id/IV_group"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"   
    android:contentDescription="group image"    

        />
</LinearLayout>

修改

存储图像路径\资源ID的方法有很多种。最简单的方法是将它们存储在ArrayList和HashMap中。

声明一个新的ArrayList和HashMap来存储Group和Child项的资源ID。

public List<Integer> groupImages; public HashMap<Integer, List<Integer>> childImages;

将其填入您的prepareListData()功能。

groupImages= new ArrayList<Integer>(); groupImages.add(R.drawable.vegetables); groupImages.add(R.drawable.fruits); groupImages.add(R.drawable.drinks); groupImages.add(R.drawable.deserts); childImages = new HashMap<Integer, List<Integer>>(); List<Integer> vegetablesi = new ArrayList<Integer>(); vegetablesi.add(R.drawable.Tomatoes); vegetablesi.add(R.drawable.Potatoes); vegetablesi.add(R.drawable.Cucumbers); vegetablesi.add(R.drawable.Pumpkins); vegetablesi.add(R.drawable.Peppers); vegetablesi.add(R.drawable.Onions); vegetablesi.add(R.drawable.Garlic); List<Integer> fruitsi = new ArrayList<Integer>(); fruitsi.add(R.drawable.Strawberries); fruitsi.add(R.drawable.Blackcurrants); fruitsi.add(R.drawable.Redcurrant); fruitsi.add(R.drawable.Gooseberry); fruitsi.add(R.drawable.Kiwifruit); fruitsi.add(R.drawable.Grape); List<Integer> drinksi = new ArrayList<Integer>(); drinksi.add(R.drawable.Vodka); drinksi.add(R.drawable.Milk); drinksi.add(R.drawable.Water); drinksi.add(R.drawable.CocaCola); drinksi.add(R.drawable.Sprite); List<Integer> desertsi = new ArrayList<Integer>(); desertsi.add(R.drawable.Vodka); desertsi.add(R.drawable.Milk); desertsi.add(R.drawable.Water); desertsi.add(R.drawable.CocaCola); desertsi.add(R.drawable.Sprite); childImages.put(groupImages.get(0), vegetablesi); childImages.put(groupImages.get(1), fruitsi); childImages.put(groupImages.get(2), drinksi); childImages.put(groupImages.get(3), desertsi);

在getGroupView和getChildView功能中，您可以通过以下方式访问这些图片：

@Override public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) { String headerTitle = (String) getGroup(groupPosition); if (convertView == null) { LayoutInflater infalInflater = (LayoutInflater) this._context .getSystemService(Context.LAYOUT_INFLATER_SERVICE); convertView = infalInflater.inflate(R.layout.list_group, null); } TextView lblListHeader = (TextView) convertView .findViewById(R.id.lblListHeader); lblListHeader.setTypeface(null, Typeface.BOLD); lblListHeader.setText(headerTitle); ImageView imageView = (ImageView) convertView.findViewById(R.id.IV_group); int imageId = this.groupImages.get(groupPosition); imageView.setImageResource(imageId); return convertView; } @Override public View getChildView(int groupPosition,final int childPosition, boolean isLastChild, View convertView, ViewGroup parent) { final String childText = (String) getChild(groupPosition, childPosition); if (convertView == null) { LayoutInflater infalInflater = (LayoutInflater) this._context .getSystemService(Context.LAYOUT_INFLATER_SERVICE); convertView = infalInflater.inflate(R.layout.list_item, null); } TextView txtListChild = (TextView) convertView .findViewById(R.id.lblListItem); txtListChild.setText(childText); ImageView imageView = (ImageView) convertView.findViewById(R.id.IV_child); int imageId = this.childImages.get(this.groupImages.get(groupPosition)).get(childPosition); imageView.setImageResource(imageId); return convertView; }

Answer 2

在getChildView方法中，您可以通过方法的签名来识别实际的子列表项 - 变量childPosition和groupPosition。

然后您可以使用开关结构加载相关图像。

Expandablelistview为组和子项查看不同的图像

2 个答案: