Android购物车怎么实现全选和反选的代码实现

以下是Android购物车实现全选和反选的代码实现，供参考：

1. 在购物车列表中添加一个全选的CheckBox，并设置其状态为未选中：

CheckBox cbSelectAll = findViewById(R.id.cb_select_all);
cbSelectAll.setChecked(false);

2. 在Adapter中实现全选和反选的逻辑：

public class ShoppingCartAdapter extends RecyclerView.Adapter<ShoppingCartAdapter.ViewHolder> {
    // 全选状态
    private boolean isSelectAll = false;
    
    // 全选按钮的点击事件
    public void selectAll() {
        isSelectAll = !isSelectAll;
        notifyDataSetChanged();
    }
    
    // 反选按钮的点击事件
    public void reverseSelect() {
        isSelectAll = false;
        notifyDataSetChanged();
    }
    
    // 获取全选状态
    public boolean isSelectAll() {
        return isSelectAll;
    }

    // ViewHolder中的CheckBox的点击事件
    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        final Goods goods = mGoodsList.get(position);
        holder.cbSelected.setChecked(goods.isSelected());
        holder.cbSelected.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                goods.setSelected(!goods.isSelected());
                notifyDataSetChanged();
            }
        });
    }

    // 全选和反选的实现
    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        final Goods goods = mGoodsList.get(position);
        holder.cbSelected.setChecked(goods.isSelected());
        holder.cbSelected.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                goods.setSelected(!goods.isSelected());
                if (isSelectAll()) {
                    for (Goods g : mGoodsList) {
                        if (!g.isSelected()) {
                            isSelectAll = false;
                            break;
                        }
                    }
                } else {
                    boolean isAllSelected = true;
                    for (Goods g : mGoodsList) {
                        if (!g.isSelected()) {
                            isAllSelected = false;
                            break;
                        }
                    }
                    if (isAllSelected) {
                        isSelectAll = true;
                    }
                }
                notifyDataSetChanged();
            }
        });
    }
    
    // 全选按钮的状态改变
    public void updateSelectAllState() {
        boolean isAllSelected = true;
        for (Goods g : mGoodsList) {
            if (!g.isSelected()) {
                isAllSelected = false;
                break;
            }
        }
        isSelectAll = isAllSelected;
        notifyDataSetChanged();
    }
}

3. 在全选按钮的点击事件中，调用Adapter的selectAll()和reverseSelect()方法：

CheckBox cbSelectAll = findViewById(R.id.cb_select_all);
cbSelectAll.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        if (mAdapter.isSelectAll()) {
            mAdapter.reverseSelect();
        } else {
            mAdapter.selectAll();
        }
    }
});

通过以上代码实现，就可以实现Android购物车的全选和反选功能了。