单纯的笔记,需深入请研究其他大神的博客,谢谢!
效果:
1.引入 依赖: compile 'com.android.support:recyclerview-v7:25.3.1'
2.activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.demo.demo10.MainActivity">
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerview"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
3.每条item布局(item.xml):
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="50dp">
<TextView
android:id="@+id/temp_item"
android:layout_width="match_parent"
android:layout_height="50dp"
android:gravity="center"
android:text="temp"/>
</LinearLayout>
4.基本分割线(DividerItemDecoration.java):
public class DividerItemDecoration extends RecyclerView.ItemDecoration {
public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
private Drawable mDivider;
private int mOrientation;
private static final int[] ATTRS = new int[]{
android.R.attr.listDivider
};
public DividerItemDecoration(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) {
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);
}
}
}
5.MyAdapter.java:
class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private Context mContext;
private List<String> mDatas;
public MyAdapter(Context context) {
this.mContext = context;
mDatas = new ArrayList<>();
initData();
}
private void initData() {
for (int i = 'a'; i <= 'z'; i++) {
mDatas.add((char) i + "");
}
}
/**
* 点击和长按监听
*/
public interface OnItemClickListener {
void onItemClick(View view, int position);
void onItemLongClick(View view, int position);
}
private OnItemClickListener mOnItemClickListener;
public void setOnItemClickListener(OnItemClickListener listener) {
this.mOnItemClickListener = listener;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
MyViewHolder holder = new MyViewHolder(LayoutInflater.from(mContext).inflate(R.layout.item, parent, false));
return holder;
}
@Override
public void onBindViewHolder(final MyViewHolder holder, final int position) {
String str = mDatas.get(position);
holder.textView.setText(str);
//自定义点击事件和长按事件
if (mOnItemClickListener != null) {
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int layoutPosition = holder.getLayoutPosition();//避免添加item时不刷新item索引
mOnItemClickListener.onItemClick(holder.itemView, layoutPosition);
}
});
holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
int layoutPosition = holder.getLayoutPosition();//避免添加item时不刷新item索引
mOnItemClickListener.onItemLongClick(holder.itemView, layoutPosition);
return true;
}
});
}
}
@Override
public int getItemCount() {
return mDatas.size();
}
class MyViewHolder extends RecyclerView.ViewHolder {
TextView textView;
public MyViewHolder(View itemView) {
super(itemView);
textView = (TextView) itemView.findViewById(R.id.temp_item);
}
}
/**
* 添加 item
*/
public void addItem(int position) {
mDatas.add(position, "添加了数据");
notifyItemInserted(position);//切记不要写成notifyDataSetChanged()
}
/**
* 删除item
*/
public void removeItem(int position) {
mDatas.remove(position);
Toast.makeText(mContext, "删除成功", Toast.LENGTH_SHORT).show();
notifyItemRemoved(position);//切记不要写成notifyDataSetChanged()
}
}
6.MainActivity.java:
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private MyAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView = (RecyclerView) findViewById(R.id.recyclerview);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
adapter = new MyAdapter(this);
mRecyclerView.setAdapter(adapter);
mRecyclerView.setItemAnimator(new DefaultItemAnimator());//设置自动增删动画
mRecyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));
adapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() {
@Override
public void onItemClick(View view, int position) {
Toast.makeText(MainActivity.this, "单击了第" + (position + 1) + "条item", Toast.LENGTH_SHORT).show();
}
@Override
public void onItemLongClick(View view, int position) {
adapter.removeItem(position);//长按删除
}
});
}
}
项目中根据实际需求更改分割线和每个item样式.