Android 如何在可扩展listview的某些子视图上动态显示图像

我试图弄清楚如何在可展开的listview中仅在一些子视图上显示图像。我需要根据组和子索引设置它。我试着按索引这样做：

public View getChildView(final int groupPosition, final int childPosition,
        boolean isLastChild, View convertView, ViewGroup parent) {
    final String laptop = (String) getChild(groupPosition, childPosition);
    LayoutInflater inflater = context.getLayoutInflater();

    if (convertView == null) {
        convertView = inflater.inflate(R.layout.child_item, null);
    }

    ImageView email = (ImageView) convertView.findViewById(R.id.email);
    //this shows the email icon where applicable
    if (groupPosition == 0 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    }
    if (groupPosition == 2 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    }

    item.setText(Html.fromHtml(laptop));
    return convertView;
}

public View getChildView(final int groupPosition, final int childPosition,
        boolean isLastChild, View convertView, ViewGroup parent) {
    final String laptop = (String) getChild(groupPosition, childPosition);
    LayoutInflater inflater = context.getLayoutInflater();

    View newView = inflater.inflate(R.layout.child_item, null);

    ImageView email = (ImageView) newView.findViewById(R.id.email);
    //this shows the email icon where applicable
    if (groupPosition == 0 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    } else
    if (groupPosition == 2 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    } else {
        email.setVisibility(View.VISIBLE);
    }

    item.setText(Html.fromHtml(laptop));
    return newView;
}

---

但是，当你开始向下滚动时，它开始将不同的设置为“消失”，因为回收工作是如何进行的。如何修复此问题以使其正常工作？

从外观上看，您不需要回收视图。如果你没有必要，就不要这样做。（所有的文档都让它听起来像一个要求，所有的例子都使用它，但它不是必需的。这只是“良好实践”，但当“良好实践”需要10倍于完成工作所需的时间时，它真的不是一个好实践，是吗？？）

回收利用背后的概念与滚动浏览一长串物品有关。如果您的列表只包含几个项目，则不需要这样做

如果您最终需要，这将修复您的代码：

ImageView email = (ImageView) convertView.findViewById(R.id.email);
//this shows the email icon where applicable
if (groupPosition == 0 && childPosition == 0 ){
    email.setVisibility(View.GONE);
} else
if (groupPosition == 2 && childPosition == 0 ){
    email.setVisibility(View.GONE);
} else {
    email.setVisibility(View.VISIBLE);
}

如果不想循环使用视图，只需忽略以下内容：

public View getChildView(final int groupPosition, final int childPosition,
        boolean isLastChild, View convertView, ViewGroup parent) {
    final String laptop = (String) getChild(groupPosition, childPosition);
    LayoutInflater inflater = context.getLayoutInflater();

    if (convertView == null) {
        convertView = inflater.inflate(R.layout.child_item, null);
    }

    ImageView email = (ImageView) convertView.findViewById(R.id.email);
    //this shows the email icon where applicable
    if (groupPosition == 0 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    }
    if (groupPosition == 2 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    }

    item.setText(Html.fromHtml(laptop));
    return convertView;
}

public View getChildView(final int groupPosition, final int childPosition,
        boolean isLastChild, View convertView, ViewGroup parent) {
    final String laptop = (String) getChild(groupPosition, childPosition);
    LayoutInflater inflater = context.getLayoutInflater();

    View newView = inflater.inflate(R.layout.child_item, null);

    ImageView email = (ImageView) newView.findViewById(R.id.email);
    //this shows the email icon where applicable
    if (groupPosition == 0 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    } else
    if (groupPosition == 2 && childPosition == 0 ){
        email.setVisibility(View.GONE);
    } else {
        email.setVisibility(View.VISIBLE);
    }

    item.setText(Html.fromHtml(laptop));
    return newView;
}

---

嗯，好吧，这很容易，我不知道我可以选择不回收视图。这是一个简单的改变，不回收他们？我编辑了我的答案演示如何不回收-convertView用于回收，它可以是一个痛苦。。。