1. 导入 v7 包
implementation 'com.android.support:recyclerview-v7:28.0.0'
2. 使用 RecyclerView
MainActivity.java
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private List<String> mList = new ArrayList<>();
private HomeAdapter mAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initData();
mRecyclerView = findViewById(R.id.recycler_view);
LinearLayoutManager manager = new LinearLayoutManager(this);
manager.setOrientation(LinearLayoutManager.VERTICAL);
mRecyclerView.setLayoutManager(manager);
mRecyclerView.setAdapter(mAdapter);
mAdapter.setOnItemClickListener(new HomeAdapter.OnItemClickListener() {
@Override
public void onClick(int position) {
Toast.makeText(MainActivity.this,"点击了"+position,Toast.LENGTH_SHORT).show();
}
@Override
public void onLongClick(final int position) {
new AlertDialog.Builder(MainActivity.this)
.setTitle("确认删除嘛")
.setNegativeButton("取消",null)
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
mAdapter.removeData(position);
}
})
.show();
}
});
}
private void initData() {
for (int index = 0;index < 10;index++){
mList.add("android");
}
mAdapter = new HomeAdapter();
mAdapter.setData(mList);
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</android.support.constraint.ConstraintLayout>
3. 适配器
item_recycler.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp">
<ImageView
android:id="@+id/iv_icon"
android:layout_width="80dp"
android:layout_height="80dp"
android:src="@drawable/ic_logo"
android:layout_gravity="center_vertical"/>
<TextView
android:id="@+id/tv_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="android"
android:textSize="18sp"
android:layout_gravity="center_vertical"
android:layout_marginLeft="10dp"/>
</LinearLayout>
HomeAdapter.java
/**
* Created on 2019/6/13 11:45 AM
*
* @author Scarf Gong
*/
public class HomeAdapter extends RecyclerView.Adapter<HomeAdapter.ViewHolder> {
private List<String> mList = new ArrayList<>();
static class ViewHolder extends RecyclerView.ViewHolder {
ImageView fruitImage;
TextView fruitName;
public ViewHolder(View itemView) {
super(itemView);
fruitImage = itemView.findViewById(R.id.iv_icon);
fruitName = itemView.findViewById(R.id.tv_title);
}
}
public void setData(List<String> list) {
this.mList.clear();
this.mList.addAll(list);
notifyDataSetChanged();
}
public void removeData(int position) {
mList.remove(position);
notifyItemRemoved(position);
notifyDataSetChanged();
}
public void addData(int position) {
mList.add(position,"ios");
notifyItemInserted(position);
}
@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int position) {
return new ViewHolder(LayoutInflater.from(parent.getContext())
.inflate(R.layout.item_recycler, parent, false));
}
@Override
public void onBindViewHolder(@NonNull ViewHolder holder, final int position) {
if (position % 2 == 0) {
holder.itemView.setBackgroundColor(Color.parseColor("#191977d3"));
} else {
holder.itemView.setBackgroundColor(Color.parseColor("#fafafa"));
}
if (mOnItemClickListener != null) {
holder.fruitImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mOnItemClickListener.onClick(position);
}
});
holder.fruitImage.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
mOnItemClickListener.onLongClick(position);
return true;
}
});
}
}
@Override
public int getItemCount() {
return mList == null ? 0 : mList.size();
}
public interface OnItemClickListener {
void onClick(int position);
void onLongClick(int position);
}
private OnItemClickListener mOnItemClickListener;
public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
mOnItemClickListener = onItemClickListener;
}
}
4. 设置分割线
用 mRecyclerView.addItemDecoration() 来加入分割线，谷歌没有提供默认的分割线需要我们继承 RecyclerView.ItemDecoration 来自定义分割线：
/**
* Created on 2019/6/13 1:50 PM
*
* @author Scarf Gong
*/
public class DividerItemDecoration 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 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. 效果图
rv.jpg
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