Android Listview OnClickListener

Question

我有一个列表视图，其中包含图像列表行和两个按钮。该列表从 JSON 加载。我正在尝试隐藏我单击的一行中的按钮。

我通过在BaseAdapter的getView中调用onclicklistener按钮尝试了

问题

当我连续点击一个按钮时。其他一些行的按钮被隐藏。我没有看到当前行按钮隐藏。

Toast 消息显示了我单击的按钮的正确文本，如下面的代码所示

BaseAdapter/getView

public View getView(final int position, View convertView, ViewGroup parent) {

final ViewHolder holder;
newsItem = listData.get(position);
if (convertView == null) {
        convertView = layoutInflater.inflate(R.layout.home_single_image, null);
    }
    holder.caption1View = (Button) convertView.findViewById(R.id.btnpos);

    holder.caption1View.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            HomeListItem newsItem1 = listData.get(position);
            Toast.makeText(c,newsItem1.getCaption1(),Toast.LENGTH_LONG).show();// shows the correct position button text
             holder.caption1View.setVisibility(View.GONE);
        }
    });

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

Answer 1

您应该将 isVisible 变量添加到 HomeListItem 类。然后添加这些方法

class HomeListItem {
...
private boolean isVisible;

private boolean isVisible() {return isVisible};
private void setIsVisible(boolean b) { isVisible = b;}

将此代码添加到getView() 方法

if(HomeListItem.isVisible()){
 holder.caption1View.setVisibility(View.VISIBLE);
} else {
 holder.caption1View.setVisibility(View.GONE);
}

在你的点击监听器中你应该这样做

HomeListItem newsItem1 = listData.get(position);
boolean prevVisibility = newsItem1.isVisible();
newsItem1.setIsVisible(!prevVisibility);
notifyDataSetChanged();

完整的代码

public View getView(final int position, View convertView, ViewGroup parent) {

final ViewHolder holder;
newsItem = listData.get(position);
..
  if(newsItem.isVisible()){
     holder.caption1View.setVisibility(View.VISIBLE);
    } else {
     holder.caption1View.setVisibility(View.GONE);
    }
holder.caption1View.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
          boolean prevVisibility = newsItem.isVisible();
          newsItem.setIsVisible(!prevVisibility);
          notifyDataSetChanged();
    }
});

... }

问题是 ListView 重用了视图，所以当你这样做时 holder.caption1View.setVisibility(View.GONE); 如果你不更新它就会消失。

Answer 2

这是因为适配器重用了视图。这意味着当您在行上设置caption.setVisibility(View.GONE) 时，您不仅会影响这一行，还会影响将重用该视图的另一行。

您需要保留隐藏按钮的索引，或任何其他可以让您决定按钮是否应该隐藏一行的方法。

然后在 getView 方法的末尾添加这些行。

if (buttonShouldBeVisibileForIndex(position)) {//<= this is the method you need to implement
     holder.caption.setVisible(View.GONE);
} else {
     holder.caption.setVisible(View.VISIBLE);
}

Answer 3

试试这个

public View getView(final int position, View convertView, ViewGroup parent) {

        final ViewHolder holder;
        if (convertView == null) {
            convertView = layoutInflater.inflate(R.layout.home_single_image, null);
            holder = new ViewHolder();
            holder.caption1View = (Button) convertView.findViewById(R.id.btnpos);
            convertView.setTag(holder);
        }else {
            holder = (ViewHolder) convertView.getTag();
        }

        newsItem = listData.get(position);


        holder.caption1View.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                HomeListItem newsItem1 = listData.get(position);
                Toast.makeText(c, newsItem1.getCaption1(), Toast.LENGTH_LONG).show();// shows the correct position button text
                holder.caption1View.setVisibility(View.GONE);
            }
        });

        return convertView;
    }