public class PreviewRecycleView extends RecyclerView {
public PreviewRecycleView(Context context, AttributeSet attrs)
{
super(context, attrs);
// TODO Auto-generated constructor stub
this.setOnScrollListener(new OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
/**
*
* 滚动时,判断当前第一个View是否发生变化,发生才回调
*/
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
View newView = getChildAt(0);
if (mItemScrollChangeListener != null)
{
if (newView != null && newView != mCurrentView)
{
mCurrentView = newView ;
mItemScrollChangeListener.onChange(mCurrentView,
getChildPosition(mCurrentView));
}
}
}
});
}
/**
* 记录当前第一个View
*/
private View mCurrentView;
private OnItemScrollChangeListener mItemScrollChangeListener;
public void setOnItemScrollChangeListener(
OnItemScrollChangeListener mItemScrollChangeListener)
{
this.mItemScrollChangeListener = mItemScrollChangeListener;
}
public interface OnItemScrollChangeListener
{
void onChange(View view, int position);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b)
{
super.onLayout(changed, l, t, r, b);
mCurrentView = getChildAt(0);
if (mItemScrollChangeListener != null)
{
mItemScrollChangeListener.onChange(mCurrentView,
getChildPosition(mCurrentView));
}
}
}
public class RecycleViewAdapter extends RecyclerView.Adapter<RecycleViewAdapter.ViewHolder> {
/**
* ItemClick的回调接口
*
*/
public interface OnItemClickLitener
{
void onItemClick(View view, int position);
}
private OnItemClickLitener mOnItemClickLitener;
public void setOnItemClickLitener(OnItemClickLitener mOnItemClickLitener)
{
this.mOnItemClickLitener = mOnItemClickLitener;
}
private LayoutInflater mInflater;
private List mDatas;
public RecycleViewAdapter(Context context, List datats)
{
mInflater = LayoutInflater.from(context);
mDatas = datats;
}
public static class ViewHolder extends RecyclerView.ViewHolder
{
public ViewHolder(View arg0)
{
super(arg0);
}
ImageView mImg;
}
@Override
public int getItemCount()
{
return mDatas.size();
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i)
{
View view = mInflater.inflate(R.layout.activity_index_gallery_item,
viewGroup, false);
ViewHolder viewHolder = new ViewHolder(view);
viewHolder.mImg = (ImageView) view
.findViewById(R.id.id_index_gallery_item_image);
return viewHolder;
}
@Override
public void onBindViewHolder(final ViewHolder viewHolder, final int i)
{
viewHolder.mImg.setImageResource(mDatas.get(i));
//如果设置了回调,则设置点击事件
if (mOnItemClickLitener != null)
{
viewHolder.itemView.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
mOnItemClickLitener.onItemClick(viewHolder.itemView, i);
}
});
}
}
}
public class MainActivity extends AppCompatActivity {
private PreviewRecycleView mRecyclerView;
private RecycleViewAdapter mAdapter;
private List mDatas;
private ImageView mImg ;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
mImg = (ImageView) findViewById(R.id.id_content);
initData();
mRecyclerView = (PreviewRecycleView) findViewById(R.id.id_recyclerview_horizontal);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
linearLayoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
mRecyclerView.setLayoutManager(linearLayoutManager);
mAdapter = new RecycleViewAdapter(this, mDatas);
mRecyclerView.setAdapter(mAdapter);
mRecyclerView.setOnItemScrollChangeListener(new PreviewRecycleView.OnItemScrollChangeListener()
{
@Override
public void onChange(View view, int position)
{
mImg.setImageResource(mDatas.get(position));
};
});
mAdapter.setOnItemClickLitener(new RecycleViewAdapter.OnItemClickLitener()
{
@Override
public void onItemClick(View view, int position)
{
Toast.makeText(getApplicationContext(), position + "", Toast.LENGTH_SHORT)
.show();
mImg.setImageResource(mDatas.get(position));
}
});
}
/*
初始化数据
*/
private void initData() {
mDatas=new ArrayList(
Arrays.asList(
R.mipmap.a,R.mipmap.b,R.mipmap.c,R.mipmap.d,
R.mipmap.e,R.mipmap.f,R.mipmap.g,R.mipmap.h,
R.mipmap.r,R.mipmap.g,R.mipmap.k,R.mipmap.l,
R.mipmap.m,R.mipmap.n,R.mipmap.o
)
);
}
}
"1.0" encoding="utf-8"?>
"http://schemas.android.com/apk/res/android"
android:layout_width="120dp"
android:layout_height="120dp">
"@+id/id_index_gallery_item_image"
android:layout_width="80dp"
android:layout_height="80dp"
android:layout_centerInParent="true"
android:layout_margin="5dp"
android:scaleType="centerCrop" />
"http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
"fill_parent"
android:layout_height="0dp"
android:layout_weight="1" >
"@+id/id_content"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="center"
android:layout_margin="10dp"
android:scaleType="centerCrop"
android:src="@mipmap/ic_launcher" />
"@+id/id_recyclerview_horizontal"
android:layout_width="match_parent"
android:layout_height="120dp"
android:layout_gravity="bottom"
android:scrollbars="none" />
Github源码地址:https://github.com/xiaokele/RecycleView_Preview