android - 将按钮作为最后一个子项添加到可扩展 ListView

Question

我需要以下问题的帮助:

有没有办法在“expendableListView”中添加一个按钮作为最后一个子项？

该按钮应位于“短文本”字段下方。

如果您需要任何进一步的信息，请发表评论，我会提供。

Answer 1

你的 ExpandableListView应该由一些数据模型支持。在每个列表项行中，您将在 View (TextView 或 Button)中显示一个文本。所以首先让自己成为一个包含这些信息的类:

public class RowData {
    public static final int TYPE_TEXT = 0;
    public static final int TYPE_BUTTON = 1;
    private String label;
    private int type;

    public RowData(String label, int type) {
        this.label = label;
        this.type = type;
    }

    public RowData(String label) {
        this.label = label;
    }

    public String getLabel() {
        return label;
    }

    public int getType() {
        return type;
    }

}

最简单的模型(因为我们不了解您的代码)是 LinkedHashMap<String, List<RowData>> .这些键指的是组数据(“00010”、“00020”、“00030”等)，而附加到这些键的每个值指的是组子项(例如，对于“00010”，您将有 ["Material Group: No找到的信息”等])。现在，在您的 Activity 中保留对此数据模型的引用:

private Map<String, List<RowData>> myData = new LinkedHashMap<String, List<RowData>>();

您需要保留对 ExpandableListView 适配器的引用:

private BaseExpandableListAdapter adapter = new CustomSpecificAdapter(yourActivityContext, myData);

当您需要添加额外的字段时，您只需将其添加到数据模型对象中即可:

myData.get("00010").add(new RowData("Button value", RowData.TYPE_BUTTON));

或 TextView : myData.get("00010").add(new RowData("TextView value"));并通知适配器:

adapter.notifyDataSetChanged();

这将更新可扩展列表。但是，您需要为每一行指定您将拥有什么样的 View ，每个位置将具有什么类型，因为这与 View 回收非常相关。所以你的相关CustomSpecificAdapter方法可能类似于:public class CustomSpecificAdapter extends BaseExpandableListAdapter

private LinkedHashMap<String, List<RowData>> modelData;
private Context context;

public CustomSpecificAdapter(Context context, LinkedHashMap<String, List<RowData>> modelData) {
    this.context = context;
    this.modelData = modelData;
}

private RowData getMyDataObj(int groupPosition, int childPosition) {
    /**
     * safe to do this since we are using a LinkedHashMap
     * */
    List<List<RowData>> children = new ArrayList<List<RowData>>(modelData.values());
    return children.get(groupPosition).get(childPosition);
}

@Override
public Object getChild(int groupPosition, int childPosition) {
    return getMyDataObj(groupPosition, childPosition);
}

@Override
public int getChildTypeCount() {
    /**
     * since you will have a button and a textview there will be 2 types of views
     * */
    return 2;
}

@Override
public int getChildType(int groupPosition, int childPosition) {
    RowData data = getMyDataObj(groupPosition, childPosition);
    if (data.getType() == RowData.TYPE_TEXT) {
        return 0;
    }
    // for button
    return 1;
}

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
    /**
     * this is the intersting part
     * */
    RowData data = getMyDataObj(groupPosition, childPosition);
    TextView myTv = null;
    if(convertView == null) {
        if(data.getType() == RowData.TYPE_BUTTON) {
            convertView = // inflate from button layout, in fact it's best to have only a <Button ... /> in the XML layout
        } else {
            convertView = // inflate from TextView layout, in fact it's best to have only a <Button ... /> in the XML layout
        }
    } 
    /**
     * Have the same id for both TextView and Button - Button extends from TextView and so setText() method is available through polimorphysm. Also no need for ViewHolder as getViewById() will refer to itself.
     * */
    myTv = (TextView) convertView.findViewById(the_same_id_in_both_xml_files);
    myTv.setText(data.getLabel());
    return convertView;
}