时间:2021-01-23 10:16:51 | 栏目:Android代码 | 点击:次
1.简介
RecyclerView是一种新的视图组,目标是为任何基于适配器的视图提供相似的渲染方式。它被作为ListView和GridView控件的继承者,在最新的support-V7版本中提供支持。RecyclerView架构,提供了一种插拔式的体验,高度的解耦,异常的灵活,通过设置它提供的不同LayoutManager,ItemDecoration , ItemAnimator实现令人瞠目的效果。
总之ListView和GridView能做的RecyclerView都能做,并且能实现瀑布流效果
2.使用
在build.gradle配置RecyclerView的库
compile 'com.android.support:recyclerview-v7:23.3.0'
//设置RecyclerView的适配器 adapter = new MyRecyclerViewAdapter(RecyclerViewActivity.this,datas); recyclerview.setAdapter(adapter); //LayoutManager recyclerview.setLayoutManager(new LinearLayoutManager(RecyclerViewActivity.this, LinearLayoutManager.VERTICAL, false)); // recyclerview.scrollToPosition(datas.size()-1); //添加RecyclerView的分割线 recyclerview.addItemDecoration(new DividerListItemDecoration(RecyclerViewActivity.this,DividerListItemDecoration.VERTICAL_LIST)); //设置动画 recyclerview.setItemAnimator(new DefaultItemAnimator());
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> { private final Context context; private final ArrayList<String> datas; public MyAdapter(Context context,ArrayList<String> datas){ this.context = context; this.datas = datas; } /** * 相当于ListView适配器中的getView的创建holder布局 * * @param parent * @param viewType * @return */ @Override public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = View.inflate(context, R.layout.item_hello, null); return new MyViewHolder(view); } @Override public void onBindViewHolder(MyViewHolder holder, int position) { holder.tv_text.setText(datas.get(position)); holder.iv_icon.setBackgroundResource(R.mipmap.ic_launcher); } @Override public int getItemCount() { return datas.size(); } class MyViewHolder extends RecyclerView.ViewHolder { private TextView tv_text; private ImageView iv_icon; public MyViewHolder(View itemView) { super(itemView); tv_text = (TextView) itemView.findViewById(R.id.tv_text); iv_icon = (ImageView) itemView.findViewById(R.id.iv_icon); } } }
3.设置ListView&GridView&瀑布流类型效果
//设置List类型效果 recyclerview.setLayoutManager(new LinearLayoutManager(RecyclerViewActivity.this,LinearLayoutManager.VERTICAL,false)); //设置Grid类型效果 recyclerview.setLayoutManager(new GridLayoutManager(RecyclerViewActivity.this, 2, GridLayoutManager.VERTICAL, false)); //recyclerview.scrollToPosition(99); //设置瀑布流类型效果 recyclerview.setLayoutManager(new StaggeredGridLayoutManager(3,StaggeredGridLayoutManager.VERTICAL));
4.分割线
参照网址:http://blog.csdn.net/lmj623565791/article/details/45059587
//设置分割线-分割线需要自定义&还可以自定义分割线的样式 //没有提供默认的分割线 recyclerview.addItemDecoration(new DividerListItemDecoration(this, DividerListItemDecoration.VERTICAL_LIST));
public class DividerListItemDecoration extends RecyclerView.ItemDecoration { private static final int[] ATTRS = new int[]{ android.R.attr.listDivider }; public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL; public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL; private Drawable mDivider; private int mOrientation; public DividerListItemDecoration(Context context, int orientation) { final TypedArray a = context.obtainStyledAttributes(ATTRS); mDivider = a.getDrawable(0); a.recycle(); setOrientation(orientation); } public void setOrientation(int orientation) { if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) { throw new IllegalArgumentException("invalid orientation"); } mOrientation = orientation; } @Override public void onDraw(Canvas c, RecyclerView parent) { // Log.e("recyclerview - itemdecoration", "onDraw()"); if (mOrientation == VERTICAL_LIST) { drawVertical(c, parent); } else { drawHorizontal(c, parent); } } public void drawVertical(Canvas c, RecyclerView parent) { final int left = parent.getPaddingLeft(); final int right = parent.getWidth() - parent.getPaddingRight(); final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); android.support.v7.widget.RecyclerView v = new android.support.v7.widget.RecyclerView(parent.getContext()); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams(); final int top = child.getBottom() + params.bottomMargin; final int bottom = top + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } public void drawHorizontal(Canvas c, RecyclerView parent) { final int top = parent.getPaddingTop(); final int bottom = parent.getHeight() - parent.getPaddingBottom(); final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams(); final int left = child.getRight() + params.rightMargin; final int right = left + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } @Override public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) { if (mOrientation == VERTICAL_LIST) { outRect.set(0, 0, 0, mDivider.getIntrinsicHeight()); } else { outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0); } } } DividerListItemDecoration
设置分割线样式:
①application设置
<!-- Base application theme. --> <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"> <!-- Customize your theme here. --> <item name="colorPrimary">@color/colorPrimary</item> <item name="colorPrimaryDark">@color/colorPrimaryDark</item> <item name="colorAccent">@color/colorAccent</item> <item name="android:listDivider">@drawable/divider_bg</item> </style>
②在activity中
<activity android:name=".recyclerview.RecyclerViewActivity" android:theme="@style/listDividerTheme"/> <style name="listDividerTheme" parent="Theme.AppCompat.Light.DarkActionBar"> <!-- Customize your theme here. --> <item name="colorPrimary">@color/colorPrimary</item> <item name="colorPrimaryDark">@color/colorPrimaryDark</item> <item name="colorAccent">@color/colorAccent</item> <item name="android:listDivider">@drawable/divider_bg</item> </style>
5.自定义设置item的点击事件
RecyclerView默认是没有点击事件的,需要自定义点击事件
用到知识点:接口,getLayoutPosition()
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder>{ private final Context context; private final ArrayList<String> datas; //设置点击某个item的监听 public interface OnItemClickListener{ void onItemClick(View view,int position,String content); } private OnItemClickListener onItemClickListener; public void setOnItemClickListener(OnItemClickListener onItemClickListener) { this.onItemClickListener = onItemClickListener; } //设置点击图片 public interface OnImageViewClickListener{ void onImageViewClick(View view,int position); } private OnImageViewClickListener onImageViewClickListener; public void setOnImageViewClickListener(OnImageViewClickListener onImageViewClickListener) { this.onImageViewClickListener = onImageViewClickListener; } ................................... class MyViewHolder extends RecyclerView.ViewHolder { private TextView tv_text; private ImageView iv_icon; public MyViewHolder(View itemView) { super(itemView); tv_text = (TextView) itemView.findViewById(R.id.tv_text); iv_icon = (ImageView) itemView.findViewById(R.id.iv_icon); //设置点击事件 itemView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if(onItemClickListener != null){ onItemClickListener.onItemClick(v,getLayoutPosition(),datas.get(getLayoutPosition())); } } }); //设置监听 iv_icon.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if(onImageViewClickListener != null){ onImageViewClickListener.onImageViewClick(v,getLayoutPosition()); } } }); } } }
在Activity中使用自定义的点击事件
//设置点击item的点击事件 myAdapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() { @Override public void onItemClick(View view, int position, String content) { Toast.makeText(RecyclerViewActivity.this, "content=="+content+",--position=="+position, Toast.LENGTH_SHORT).show(); } }); //设置点击某张图片的点击事件 myAdapter.setOnImageViewClickListener(new MyAdapter.OnImageViewClickListener() { @Override public void onImageViewClick(View view, int position) { Toast.makeText(RecyclerViewActivity.this, "position=="+position+",view=="+view.toString(), Toast.LENGTH_SHORT).show(); } });
6.删除和增加数据
1_在适配器中新增加添加和删除两个方法
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> { ........................ public void addData(int position,String content){ datas.add(position,content); notifyItemInserted(position); } public void removeData(int position){ datas.remove(position); notifyItemRemoved(position); } }
2_Activity中
btn_add.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { myAdapter.addData(0,"Content NetData"); //定位到第0个位置 recyclerview.scrollToPosition(0); } }); btn_remove.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { myAdapter.removeData(0); } });