Question

我遇到问题，其中Child Activity的列表视图更新了Parent Activity的列表视图的内容。

基本上，在我的父活动（DetailActivity）中，我有一个名为lvContacts的列表视图，我使用以下代码填充：

ListView lvDetail = (ListView)findViewById(R.id.lvContacts);
SingleLineAdapter adapter = new SingleLineAdapter(this, Items);
lvDetail.setAdapter(adapter);
lvDetail.setSelector(R.drawable.generic_selector);

其中Items是GenericDataObject的ArrayList：

public class GenericDataObject implements Serializable {
private static final long serialVersionUID = 7661717999129942666L;
private String Id;
private String Description;
private String RawData;

// getters and setters snipped for smaller code
}

SingleLineAdapter看起来像这样：

public class SingleLineAdapter extends CustomListAdapter implements Filterable {
private static ArrayList<GenericDataObject> ObjectArray;
private static ArrayList<GenericDataObject> OriginalArray;
private LayoutInflater layoutInflater;
private String SearchedText = "";
private Context OriginatingContext;

public SingleLineAdapter(Context context, ArrayList<GenericDataObject> Objects) {
    OriginatingContext = context;
    ObjectArray = Objects;
    OriginalArray = Objects;
    layoutInflater = LayoutInflater.from(context);
    if (Objects != null)
        Collections.sort(Objects, ObjectComparator);
}

private Comparator<GenericDataObject> ObjectComparator = new Comparator<GenericDataObject>() {
    @Override
    public int compare(GenericDataObject object1,
            GenericDataObject object2) {
        return object1.getDescription().compareTo(object2.getDescription());
    }
};

@Override
public int getCount() {
    return ObjectArray.size();
}

@Override
public Object getItem(int position) {
    return ObjectArray.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    ViewHolder holder;
    if (convertView == null) {
        convertView = layoutInflater.inflate(R.layout.listitem_generic, null);
           holder = new ViewHolder();
           holder.lblTitle = (TextView)convertView.findViewById(R.id.lblTitle);

           convertView.setTag(holder);
          } else {
           holder = (ViewHolder) convertView.getTag();
    }

    holder.lblTitle.setText(ObjectArray.get(position).getDescription(), TextView.BufferType.SPANNABLE);

    if (!SearchedText.equals("")) {
        Spannable wordToSpan = (Spannable)holder.lblTitle.getText();
        String[] comps;
        if (SearchedText.startsWith("\""))
            comps = new String[] { SearchedText.substring(1, SearchedText.length() - 1) };
        else
            comps = SearchedText.split(" ");

        String name = holder.lblTitle.getText().toString().toLowerCase();
        for(int i = 0; i < comps.length; i++) {
            int Start = name.indexOf(comps[i]);
            while (Start > -1) {
                int End = Start + comps[i].length();
                wordToSpan.setSpan(new BackgroundColorSpan(0xFFFF9900), Start, End, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
                Start = name.indexOf(comps[i], End);
            }
        }
    }
    setFont(holder.lblTitle);

    return convertView;
}

static class ViewHolder {
    TextView lblTitle;
}

@Override
public Filter getFilter() {
    return new Filter() {

        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            SearchedText = constraint.toString();
            final FilterResults result = new FilterResults();

            final ArrayList<GenericDataObject> custs = new ArrayList<GenericDataObject>();
            if(constraint != null) {
                String[] searches;
                if (constraint.toString().startsWith("\"") && constraint.toString().endsWith("\""))
                    searches = new String[] { SearchedText.substring(1, SearchedText.length() - 1) };
                else
                    searches = constraint.toString().split(" ");
                for(int i = 0; i < OriginalArray.size(); i++) {
                    String customerName = OriginalArray.get(i).getDescription().toLowerCase();

                    boolean bNotFound = false;
                    for(int j = 0; j < searches.length && bNotFound == false; j++) {
                        String searchFor = searches[j];
                        if (!customerName.contains(searchFor))
                            bNotFound = true;
                    }

                    if (!bNotFound)
                    {
                        custs.add(OriginalArray.get(i));
                    }
                }
                result.values = custs;
            }
            return result;
        }

        @Override
        @SuppressWarnings("unchecked")
        protected void publishResults(CharSequence constraint,
                FilterResults results) {
            ObjectArray = (ArrayList<GenericDataObject>)results.values;
            notifyDataSetChanged();
        }
    };
}
}

OnItemClick for lvContacts对Web服务上的数据的查询然后显示一个新的Activity：

Intent detail = new Intent(DetailActivity.this, ContactDetailActivity.class);
detail.putExtra("ListOfDetails", RowsFromService);
startActivity(detail);

RowsFromService也是GenericDataObject的ArrayList。

在ContactDetailActivity中，我有一个名为lvContactDetail的ListView。我填写这个：

@Override
protected void onCreate(Bundle savedInstanceState) {
    ArrayList<GenericDataObject> DetailRows = (ArrayList<GenericDataObject>)getIntent().getExtras().getSerializable("ListOfDetails");
    ListView lvContactDetail = (ListView)findViewById(R.id.lvContactDetail);
    SingleLineAdapter detailAdapter = new SingleLineAdapter(this, DetailRows);
    lvContactDetail.setAdapter(detailAdapter);
    lvContactDetail.setSelector(R.drawable.generic_selector);
}

到目前为止，所有内容都能完美运行，但如果我使用后退按钮甚至按钮上的activity.finish（）返回到DetailActivity（父活动），则原始列表（lvContacts）现在会填充结果of lvContactDetail。

这只发生在我的应用程序中的两个列表中，其余列表都正常工作。

从其他列表中加载列表时是否有任何特殊的预防措施需要注意？值得注意的是，我的应用程序中的主要活动为CLEAR_TOP和REORDER_TO_FRONT设置了标志......

奇怪的是：即使我在子活动中注释掉setAdapter行，父活动也会继续使用其他活动的数据进行更新。这可能与创建SingleLineAdapter的新实例有关吗？

Answer 1

似乎我是唯一真正遇到此问题的人，所以我所做的就是在onCreate中“重新加载”父活动的UI部分。（保持布尔值以指示数据是否已加载）

子活动ListView更新父活动的ListView

1 个答案: