效果图
效果图- 布局文件中只包含RecyclerView
- MainActivity中代码如下:
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerview;
private MyAdapter mAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerview = findViewById(R.id.recyclerview);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
recyclerview.setLayoutManager(linearLayoutManager);
recyclerview.setAdapter(mAdapter = new MyAdapter());
recyclerview.addItemDecoration(new DividerItemDecoration(this, OrientationHelper.VERTICAL));
}
@Override
public boolean onContextItemSelected(MenuItem item) {
mAdapter.removeItem(mAdapter.getPosition());
return super.onContextItemSelected(item);
}
}
- Adapter代码
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private List<String> mData = new ArrayList<>();
private int mPosition = -1;
public int getPosition() {
return mPosition;
}
public void setPosition(int position) {
this.mPosition = position;
}
public void removeItem(int position) {
mData.remove(position);
notifyDataSetChanged();
}
public MyAdapter() {
String data;
for (int i = 0; i < 100; i++) {
data = "item_" + i;
mData.add(data);
}
}
@Override
public MyAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
TextView tv = new TextView(parent.getContext());
tv.setTextSize(20);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(-1, -2);
tv.setLayoutParams(lp);
return new MyAdapter.MyViewHolder(tv);
}
@Override
public void onBindViewHolder(final MyAdapter.MyViewHolder holder, final int position) {
holder.tv.setText(mData.get(position));
holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
mPosition = holder.getAdapterPosition();
return false;
}
});
}
@Override
public int getItemCount() {
return mData.size();
}
static class MyViewHolder extends RecyclerView.ViewHolder implements View.OnCreateContextMenuListener {
TextView tv;
public MyViewHolder(View itemView) {
super(itemView);
tv = (TextView) itemView;
itemView.setOnCreateContextMenuListener(this);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
menu.add(0, 0, 0, "删除");
}
}
}
注意点:
: 1.在ViewHolder中添加itemView.setOnCreateContextMenuListener(this);
: 2.在ViewHolder中重写onCreateContextMenu添加菜单
: 3.在adapter中定义一个属性mPosition记录当前长按点击的位置
: 4.在onBindViewHolder中为itemView设置onLongClick事件
: holder.itemView.setOnLongClickListener(new View.OnLongClickListener() { @Override public boolean onLongClick(View v) { mPosition = holder.getAdapterPosition(); return false; } });
: 5.在Activity中重写onContextItemSelected方法实现上下文点击的操作。
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