【发布时间】：2011-03-20 15:05:23
【问题描述】：
这一定是我忽略的非常简单的事情，但我有以下问题（帖子相当长，但我想提供尽可能多的信息:)）。
我的 Android 应用程序中有一个 gridview，其中每个单元格都包含自定义视图：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<GridView
android:id = "@+id/photosGridView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clickable="true"
android:drawSelectorOnTop="true"
android:focusable="true"
android:focusableInTouchMode="true"
android:numColumns="6"
android:columnWidth="90dp"
android:verticalSpacing="5dp"
android:horizontalSpacing="5dp"
android:stretchMode="columnWidth"
>
</GridView>
</RelativeLayout>
每个单元格都是
<?xml version="1.0" encoding="utf-8"?>
<com.myapp.widgets.ImageThumbView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background = "@android:color/transparent"
android:paddingLeft = "1dip"
android:paddingRight = "1dip"
android:paddingTop = "2dip"
android:paddingBottom = "2dip"
>
<ImageView
android:id="@+id/thumbImage"
android:layout_width="fill_parent"
android:layout_height = "fill_parent"
android:src="@drawable/icon_small"
/>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height = "fill_parent"
android:background = "@android:color/transparent"
>
<ImageView
android:id="@+id/iconRight"
android:layout_width="40px"
android:layout_height = "40px"
android:src="@drawable/album_check"
android:visibility="gone"
android:layout_alignParentTop = "true"
android:layout_alignParentRight = "true"
/>
<ImageView
android:id="@+id/iconLeft"
android:src="@drawable/album_check"
android:visibility="gone"
android:layout_width = "40px"
android:layout_height="40px"
android:layout_alignParentTop = "true"
android:layout_alignParentLeft = "true"
/>
</RelativeLayout>
</com.myapp.widgets.ImageThumbView>
我的适配器如下所示：
public class ImageAdapter extends BaseAdapter {
private List<String> mPictures = null;
public ImageAdapter(List<String> pictures) {
mPictures = pictures;
}
public int getCount() {
return mPictures != null ? mPictures.size() : 0;
}
public Object getItem(int position) {
return mPictures != null ? mPictures.get(position) : null;
}
public long getItemId(int position) {
return mPictures != null ? position : -1;
}
@Override
public View getView(int position,View convertView,ViewGroup parent)
{
ImageThumbView i = null;
try
{
Thread.sleep(100);
if (convertView == null)
{
String path = mPictures.get(position);
Log.d(((Integer)position).toString(), path);
i = addSingleView(_li, path);
TextView idx = (TextView) i.findViewById(R.id.caption);
if (idx != null)
idx.setText(((Integer)position).toString());
}
else
{
Log.d(((Integer)position).toString(), "ALREADY NOT NULL");
i = (ImageThumbView) convertView;
// These 2 lines were added only in desperate attempt to get it working, but it makes no difference
String path = mPictures.get(position);
i.updateView(path);
}
}
catch(InterruptedException ie)
{
ie.printStackTrace();
}
return i;
}
}
所以最初它可以正常工作，即它显示前 18 个图像和下一行的几个像素。但是当我开始滚动gridvew 时，图像开始随机出现，即在最后一张图像之后，我从一开始就很少看到等等。出于好奇，我尝试了几个这样的示例：http://androidsamples.blogspot.com/2009/06/how-to-display-thumbnails-of-images.html ...并看到相同的结果。
那么，我做错了什么吗？为什么 GridView 会显示比它应该做的更多的项目？为什么项目出现在错误的位置？
BR, 亚历克斯
【问题讨论】：