Question

我试图在Android中实现3级ExpandableListView。

它看起来像这样：

1级
- 等级2
- 等级2
  - 等级3
- 等级2
1级
- 等级2
- 等级2

2级和3级应该有CheckBox - es。当选择级别2中的CheckBox时，也会选择级别3中的所有孩子。

我已经完成了2个适配器 - 都扩展了BaseExpandableListAdapter。所以最后我得到2个插入ExpandableListView - s - 一个用于等级1 - 等级2，另一个用于等级2 - 等级3。

此外，我有2个单独的布局 - 一个用于第一级，一个用于第2-3级（因为它们是相同的）。它s just a的TextView with id inside RelativeView`。

问题：

当我将TextView更改为CheckBox es并将文本设置为它们时，我无法将列表扩展到第三级。我不明白它为什么会发生以及如何处理它，有人可以帮助我吗？
如何从没有孩子的2级项目中隐藏指标（显示展开/折叠状态的箭头）？
我不知道为什么我的ExpandableListView并不想垂直适合所有屏幕，它只消耗1/4。我试图改变CustomExpandableListView中的一些参数，但它没有用。

这里有一些截图：

截屏1： [Screenshot 1]

截屏2： [Screenshot 2]

如您所见，当我扩展亚洲名单时，欧洲名单隐藏起来。

这是第1级的代码：

public class RegionsAdapter extends BaseExpandableListAdapter {

private List<Object> objects;
private Activity activity;
private LayoutInflater inflater;

public RegionsAdapter(Activity activity, List<Object> objects) {
    this.objects = objects;
    this.activity = activity;
    this.inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public Object getChild(int groupPosition, int childPosition) {
    return objects.get(groupPosition).getObjects().get(childPosition);
}

@Override
public long getChildId(int groupPosition, int childPosition) {
    return childPosition;
}

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

    Object object = (Object) getChild(groupPosition, childPosition);
    CustomExpandableListView subObjects = (CustomExpandableListView) convertView;

    if (convertView == null) {
        subObjects = new CustomExpandableListView(activity);
    }
    CountriesAdapter adapter = new CountriesAdapter(activity, object);
    subObjects.setAdapter(adapter);

    return subObjects;
}

@Override
public int getChildrenCount(int groupPosition) {
    return objects.get(groupPosition).getObjects().size();
}

@Override
public Object getGroup(int groupPosition) {
    return objects.get(groupPosition);
}

@Override
public int getGroupCount() {
    return objects.size();
}

@Override
public long getGroupId(int groupPosition) {
    return groupPosition;
}

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

    Object object = (Object) getGroup(groupPosition);
    if (convertView == null) {
        convertView = inflater.inflate(R.layout.layout_region_item, null);
    }

    TextView name = (TextView) convertView.findViewById(R.id.name);
    name.setText(object.getName());

    return convertView;
}

@Override
public boolean hasStableIds() {
    return true;
}

@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
    return true;
}
}

级别2-3的代码：

public class CountriesAdapter extends BaseExpandableListAdapter {

private Object object;
private LayoutInflater inflater;
private Activity activity;

public CountriesAdapter(Activity activity, Object object) {
    this.activity = activity;
    this.object = object;
    this.inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public Object getChild(int groupPosition, int childPosition) {
    return object.getObjects().get(childPosition);
}

@Override
public long getChildId(int groupPosition, int childPosition) {
    return childPosition;
}

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

    Object object = (Object) getChild(0, childPosition);
    if (convertView == null) {
        convertView = inflater.inflate(R.layout.layout_country_item, null);

        Resources r = activity.getResources();
        float px40 = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 40, r.getDisplayMetrics());
        convertView.setPadding(
                convertView.getPaddingLeft() + (int) px40,
                convertView.getPaddingTop(),
                convertView.getPaddingRight(),
                convertView.getPaddingBottom());
    }

    TextView name = (TextView) convertView.findViewById(R.id.name);
    name.setText(object.getName());

    return convertView;
}

@Override
public int getChildrenCount(int groupPosition) {

    if (object.getObjects() == null) {
        return 0;
    }
    return object.getObjects().size();
}

@Override
public Object getGroup(int groupPosition) {
    return object;
}

@Override
public int getGroupCount() {
    return 1;
}

@Override
public long getGroupId(int groupPosition) {
    return groupPosition;
}

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

    if (convertView == null) {
        convertView = inflater.inflate(R.layout.layout_country_item, null);
        Resources r = activity.getResources();
        float px20 = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 20, r.getDisplayMetrics());
        convertView.setPadding(
                convertView.getPaddingLeft() + (int) px20,
                convertView.getPaddingTop(),
                convertView.getPaddingRight(),
                convertView.getPaddingBottom());
    }

    TextView name = (TextView) convertView.findViewById(R.id.name);
    name.setText(object.getName());

    return convertView;
}

@Override
public boolean hasStableIds() {
    return true;
}

@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
    return true;
}
}

我还有一些自定义的ExpandableListView：

public class CustomExpandableListView extends ExpandableListView {

public CustomExpandableListView(Context context) {
    super(context);
}

protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    widthMeasureSpec = MeasureSpec.makeMeasureSpec(960, MeasureSpec.AT_MOST);
    heightMeasureSpec = MeasureSpec.makeMeasureSpec(600, MeasureSpec.AT_MOST);
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}

我的MainActivity代码：

public class MainActivity extends AppCompatActivity {

public static CustomExpandableListView list;

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

    List<Item> objectsLvl1 = new ArrayList<Item>();

    List<Item> objectsAsia = new ArrayList<Item>();
    List<Item> objectsEurope = new ArrayList<Item>();

    List<Item> objectsChina = new ArrayList<Item>();

    List<Item> objectsGermany = new ArrayList<Item>();

    objectsLvl1.add(new Item("Asia", objectsAsia));
    objectsLvl1.add(new Item("Europe", objectsEurope));

    objectsAsia.add(new Item("China", objectsChina));
    objectsAsia.add(new Item("Japan"));

    objectsChina.add(new Item("Central", null));
    objectsChina.add(new Item("North", null));
    objectsChina.add(new Item("South", null));


    RelativeLayout parent = (RelativeLayout) findViewById(R.id.parent);

    list = new CustomExpandableListView(this);
    RegionsAdapter regionsAdapter = new RegionsAdapter(this, objectsLvl1);
    list.setAdapter(regionsAdapter);

    if (parent != null) {
        parent.addView(list);
    }
}
}

Answer 1

然而，最后，我已经弄明白了。这就是答案。

使用复选框扩展列表：

这个很简单。我已在OnClickListener方法中将TextView添加到getGroupView：

    View.OnClickListener clickListener = new View.OnClickListener() {
    @Override
    public void onClick(View v) {
            if (!isExpanded) {
                expandableListView.expandGroup(groupPosition);
            } else {
                expandableListView.collapseGroup(groupPosition);
            }
        }
    };

    holder.childName.setOnClickListener(clickListener);
    holder.childIndicator.setOnClickListener(clickListener);

隐藏指标：

更换标准指标并添加我自己的指标更容易。然后，getGroupView内部使用它。

首先，将默认groupIndicator设置为null：

expandableListView.setGroupIndicator(null);

使用自定义图像：

holder.childIndicator = (ImageView) convertView.findViewById(R.id.imgChildIndicator);

    if (getChildrenCount(groupPosition) == 0) {
        holder.childIndicator.setAlpha(0);
    } else {
        holder.childIndicator.setImageResource(isExpanded ? R.drawable.expanded : R.drawable.collapsed);
    }

最后，隐藏所有Level 3项目的groupIndicator：

holder.childIndicator.setAlpha(0);

对1级项目进行了相同的更改。

在屏幕上显示ExpandableListView：

我已将ExpandableListView放入RelativeLayout activity_main内。{/ p>

改变了 MainActivity：

中的实现

ExpandableListView list = (ExpandableListView) findViewById(R.id.expandableListView_Parent);

    if (list != null) {
        ParentAdapter adapter = new ParentAdapter(this, objectsLvl1);
        list.setAdapter(adapter);
    }

这解决了我的问题，现在我有一个全屏ExpandableList。

Android中使用CheckBoxes的多级ExpandableListView

1 个答案: