Android 中带有 CheckBoxes 的多级 ExpandableListView

Question

我正在尝试在 Android 中实现 3 级 ExpandableListView。

看起来像这样：

• 1 级
  • 2 级
  • 2 级
    • 3 级
  • 2 级
• 1 级
  • 2 级
  • 2 级

Level 2 和 Level 3 应该有CheckBox-es。而当第二层CheckBox被选中时，他在第三层的所有孩子也被选中。

我已经完成了 2 个适配器 - 都扩展了 BaseExpandableListAdapter。所以最后我插入了 2 个 ExpandableListView-s - 一个用于 Level 1 - Level 2，另一个用于 Level 2 - Level 3。

我还有 2 个单独的布局 - 一个用于 1 级，一个用于 2-3 级（因为它们是相同的）。 Its just aTextViewwith id insideRelativeView`.

问题：

• 当我将 TextView 更改为 CheckBoxes 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？

• 如何从没有子级的 2 级项目中隐藏指示器（显示展开/折叠状态的箭头）？

• 我不明白为什么我的ExpandableListView 不想垂直适应所有屏幕，它只消耗了 1/4。我尝试更改 CustomExpandableListView 中的一些参数，但没有成功。

这里有一些截图：

屏幕截图 1：

屏幕截图 2：

如您所见，当我展开亚洲列表时，欧洲列表会自行隐藏。

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;
}
}

以及 2-3 级的代码：

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 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);
}
}

还有我的 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

最后我想通了。这就是答案。

• 用复选框扩展列表：

这个很简单。我在getGroupView 方法中添加了OnClickListener 到TextView：

    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，在 getGroupView 内部使用它。

首先，将默认的groupIndicator设置为null：

expandableListView.setGroupIndicator(null);

然后，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，隐藏我所有 3 级项目的 groupIndicator：

holder.childIndicator.setAlpha(0);

对 1 级项目进行了相同的更改。

• 在屏幕上安装 ExpandableListView：

我已将ExpandableListView 放入我的RelativeLayout 中activity_main。

在MainActivity中改变了实现：

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。