Android之---RecycleView实现简单的图片查看功能（类似相册查看器）
16lz
2021-01-24
RecycleView实现简单的图片查看功能（类似相册查看器）
效果图
自定义PreviewRecycleView继承自RecycleView
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)); } }}PreviewRecycleView的Adapter
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); } }); } }} MainActicity.java
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 ) ); }} 底部指示器的Item布局
<?xml version="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" /> activity_main.xml
"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
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