自定义 ArrayAdapter<Object> ViewHolder : Listview 中多个项目的 imageView 更改不仅仅是一个答案

【问题标题】：custom ArrayAdapter<Object> ViewHolder : imageView changes for several items in Listview not for one only自定义 ArrayAdapter<Object> ViewHolder : Listview 中多个项目的 imageView 更改不仅仅是一个
【发布时间】：2015-08-06 21:44:08
【问题描述】：

好的，我遇到了这个自定义 ArrayAdapter 的问题

public class AuthorsAdapter extends ArrayAdapter<Entity> {

    View row;
    static class ViewHolder {
        TextView textViewTitle;
        TextView textViewEntitySummary;
        ImageView imageViewPicture;
    }
    public AuthorsAdapter(Context context, LinkedList<Entity> entity) {
        super(context, 0, entity);
    }
    @Override
    public View getView( final int position,  View convertView,  final ViewGroup parent) {
        row = convertView;
        final ViewHolder holder;

        if (row == null) {
            row = LayoutInflater.from(getContext()).inflate(R.layout.listview_search_author_template, parent, false);
            holder = new ViewHolder();
            holder.textViewTitle = (TextView) row.findViewById(R.id.textView_TitleTopLeft);
            holder.textViewEntitySummary = (TextView) row.findViewById(R.id.textView_EntitySummary);
            holder.imageViewPicture = (ImageView) row.findViewById(R.id.imageView_author);
            row.setTag(holder);
        } else
            holder = (ViewHolder) row.getTag();


        holder.textViewTitle.setText(getItem(position).getTitle());
        if (!getItem(position).getPictureURL().isEmpty())
            Picasso.with(getContext()).load(getItem(position).getPictureURL()).into(holder.imageViewPicture);
        holder.textViewEntitySummary.setText(getItem(position).getBiography());


        holder.imageViewPicture.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (!getItem(position).isImageResized()) {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.WRAP_CONTENT));
                    getItem(position).setIsImageResized(true);
                } else if (getItem(position).isImageResized()) {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.MATCH_PARENT));
                    getItem(position).setIsImageResized(false);

                } else {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.MATCH_PARENT));

                }

            }
        });


        return row;
    }

imageView onclicklistener 一切正常：

holder.imageViewPicture.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if (!getItem(position).isImageResized()) {
                        holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.WRAP_CONTENT));
                        getItem(position).setIsImageResized(true);
                    } else if (getItem(position).isImageResized()) {
                        holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.MATCH_PARENT));
                        getItem(position).setIsImageResized(false);

                    } else {
                        holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.MATCH_PARENT));

                    }

                }
            });


}

我希望图像在点击时改变它的大小，它可以工作，但是当我在我的视图中向下滚动时，我的 listView 中的随机其他项目会受到点击第一个项目的影响......当我出现在我的 listview 中时图像不再调整大小（在我单击的索引处）任何提示可以使其完美运行？

【问题讨论】：

标签： android listview android-listview imageview

【解决方案1】：

好的，我通过引用找到了解决方法

private  LinkedList<Entity> entity;
public AuthorsAdapter(Context context, LinkedList<Entity> entity) {
    super(context, 0, entity);
    this.entity = entity;
}

在构造函数中然后不要像你说的那样做：

....  else{
              holder = (ViewHolder) convertView.getTag();
            }
                     if (!getItem(position).isImageResized()) {
                        holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.WRAP_CONTENT));
                        getItem(position).setIsImageResized(true);
                    } else if (getItem(position).isImageResized()) {
                        holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.MATCH_PARENT));
                        getItem(position).setIsImageResized(false);

                    } else {
                        holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                                LinearLayout.LayoutParams.WRAP_CONTENT,
                                LinearLayout.LayoutParams.MATCH_PARENT));

                    } .....

我做了一个这样的增强 for 循环：

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

for (Entity foo : entity) {
            if (!foo.isImageResized()) {
                holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                        25,
                        25));
            } else if (foo.isImageResized())
                holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                        LinearLayout.LayoutParams.MATCH_PARENT,
                        LinearLayout.LayoutParams.MATCH_PARENT));

        } ....

请注意，我在我的 xml 布局中做了一些更改，所以现在图像就在标题下方 :) 并且我让它匹配父级以获得更大尺寸的图像...

顺便说一句，非常感谢@Ammar aly 的提示，它真的帮助了我

【讨论】：

【解决方案2】：

public class AuthorsAdapter extends ArrayAdapter<Entity> {


    static class ViewHolder {
        TextView textViewTitle;
        TextView textViewEntitySummary;
        ImageView imageViewPicture;
    }
    public AuthorsAdapter(Context context, LinkedList<Entity> entity) {
        super(context, 0, entity);
    }
    @Override
    public View getView( final int position,  View convertView,  final ViewGroup parent) {

        final ViewHolder holder;

        if (convertView == null) {
            convertView = LayoutInflater.from(getContext()).inflate(R.layout.listview_search_author_template, parent, false);
            holder = new ViewHolder();
            holder.textViewTitle = (TextView) convertView.findViewById(R.id.textView_TitleTopLeft);
            holder.textViewEntitySummary = (TextView) convertView.findViewById(R.id.textView_EntitySummary);
            holder.imageViewPicture = (ImageView) convertView.findViewById(R.id.imageView_author);
            convertView.setTag(holder);
        } else{
          holder = (ViewHolder) convertView.getTag();
        }
                 if (!getItem(position).isImageResized()) {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.WRAP_CONTENT));
                    getItem(position).setIsImageResized(true);
                } else if (getItem(position).isImageResized()) {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.MATCH_PARENT));
                    getItem(position).setIsImageResized(false);

                } else {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.MATCH_PARENT));

                }


        holder.textViewTitle.setText(getItem(position).getTitle());
        if (!getItem(position).getPictureURL().isEmpty())
            Picasso.with(getContext()).load(getItem(position).getPictureURL()).into(holder.imageViewPicture);
        holder.textViewEntitySummary.setText(getItem(position).getBiography());


        holder.imageViewPicture.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
         if (!getItem(position).isImageResized()) {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.WRAP_CONTENT));
                    getItem(position).setIsImageResized(true);
                } else if (getItem(position).isImageResized()) {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.MATCH_PARENT));
                    getItem(position).setIsImageResized(false);

                } else {
                    holder.imageViewPicture.setLayoutParams(new LinearLayout.LayoutParams(
                            LinearLayout.LayoutParams.WRAP_CONTENT,
                            LinearLayout.LayoutParams.MATCH_PARENT));

                }

            }
        });


        return convertView;
    }

【讨论】：

有了这个似乎随机设置图像视图大小:(
好吧，让我改变答案，而不是你尝试
感谢@Ammar aly 也许我误解了一些东西，但我通过使用基于您的解决方案的增强 for 循环创建了一个解决方法......它真的帮助了我，所以我将您的答案标记为一个很好的解决方案；）