Question

我正试图从一个网站获取新闻。有些文章有图片。这是我的问题：一些文章没有图像，所以我想删除该行和标题textview的Imageview应该获取该空间。我尝试在BaseAdapter中实现它，但我认为setvisibility(View.Gone)无效。

这是我的布局文件：

<!-- Thumbnail Image -->
<com.android.volley.toolbox.NetworkImageView
    android:id="@+id/thumbnail"
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:layout_alignParentLeft="true"
    android:layout_marginRight="8dp" />

<!-- News Title -->
<TextView
    android:id="@+id/title"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:textSize="@dimen/title"
    android:ellipsize="end"
    android:textStyle="bold"
    android:layout_alignTop="@+id/thumbnail"
    android:layout_toRightOf="@+id/thumbnail"/>

这是我在基本适配器中的实现：

  NetworkImageView thumbNail = (NetworkImageView) convertView
            .findViewById(R.id.thumbnail);
    TextView title = (TextView) convertView.findViewById(R.id.title);

    // getting movie data for the row
    Movie m = movieItems.get(position);

    if(m.getThumbnailUrl() == null)
    {

     thumbNail.setVisibility(View.GONE); //Not working

    }
    else {
        thumbNail.setImageUrl(m.getThumbnailUrl(), imageLoader);
    }

目前的输出是：我希望textview使用Imageview的空白区域。

Example

当我尝试使用ViewHolder进行平滑过渡时，我无法实现此逻辑：

if (position==-1)
    {
        viewHolder.thumbnail.setVisibility(View.GONE);
    }
    else
    {
        viewHolder.thumbnail.setImageUrl(news.getThumbnailUrl(), imageLoader);
    }

Answer 1

您可以检查图片的URL是否有效，然后您可以使用Visibility gone concept。使用类似下面的代码：

if(!URLUtil.isValidUrl(m.getThumbnailUrl())){
    thumbNail.setVisibility(View.GONE);
}else {
        thumbNail.setImageUrl(m.getThumbnailUrl(), imageLoader);
        thumbNail.setVisibility(View.VISIBLE);
    }

希望这对你有所帮助。

Answer 2

试试这个：

    if(m.getThumbnailUrl() == null)
    {
     thumbNail.setVisibility(View.GONE);
     LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,  LinearLayout.LayoutParams.WRAP_CONTENT);
lp.addrule(LinearLayout.RIGHT_OF,0);
         lp.setMargins(-150,0,0,0); //set your margins for your textview as your want
         title.setLayoutParams(lp);
         Your_Linear_Layout_Name.addView(title, lp);
        //or RelativeLayoutName.addView(title, lp);
        }

        .....

Answer 3

m.getThumbnailUrl（）返回一个String，对吗？

你试过这个吗？

if(m.getThumbnailUrl() == null || TextUtils.isEmpty(m.getThumbnailUrl()))

尝试调试并检查是否点击此行：

thumbNail.setVisibility(View.GONE);

Answer 4

如果您没有以编程方式为该特定LayoutParameters设置文章集TextView的图片。

if(m.getThumbnailUrl() == null)
{

 thumbNail.setVisibility(View.GONE);
 RelativeLayout.LayoutParams layoutParams= (RelativeLayout.LayoutParams) title.getLayoutParams();
 layoutParams.addRule(RelativeLayout.RIGHT_OF,0);
 layoutParams.addRule(RelativeLayout.ALIGN_TOP,0);
 layoutParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT,RelativeLayout.TRUE);
 title.setLayoutParams(layoutParams);
}

Answer 5

这是因为ListView的工作原理。你可以尝试这样的事情：

if(m.getThumbnailUrl() == null)
    {

     thumbNail.setVisibility(View.GONE);
     LayoutParams layoutParams = title.getLayoutParams();
     layoutParams.width = ViewGroup.LayoutParams.MATCH_PARENT;
     layoutParams.height = ViewGroup.LayoutParams.WRAP_CONTENT;
     title.setLayoutParams(layoutParams); 
    }

    else {

        thumbanil.setVisibility(View.VISIBLE);
        thumbNail.setImageUrl(m.getThumbnailUrl(), imageLoader);
        LayoutParams layoutParams = title.getLayoutParams();
        layoutParams.width = ViewGroup.LayoutParams.MATCH_PARENT;
        layoutParams.height = ViewGroup.LayoutParams.WRAP_CONTENT;
        title.setLayoutParams(layoutParams); 

    }

TextView没有获取ImageView的空间

5 个答案: