//选择
selection = findViewById(R.id.selection);
selection_no = findViewById(R.id.selection_no);
ly_btn_yes = findViewById(R.id.ly_btn_yes);
ly_btn_no = findViewById(R.id.ly_btn_no);
//点击全选
selection.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (type.size() > 0) {
ly_btn_yes.setVisibility(View.VISIBLE);
ly_btn_no.setVisibility(View.VISIBLE);
selection_no.setVisibility(View.VISIBLE);
selection.setVisibility(View.GONE);
adapter.alter_state(1);
adapter.selectAll();
}
}
});
selection_no.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
selection_no.setVisibility(View.INVISIBLE);
selection.setVisibility(View.VISIBLE);
adapter.selectNoAll();
}
});
//点击取消
ly_btn_no.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
ly_btn_yes.setVisibility(View.GONE);
ly_btn_no.setVisibility(View.GONE);
selection.setVisibility(View.VISIBLE);
selection_no.setVisibility(View.INVISIBLE);
adapter.selectNoAll();
adapter.alter_state(0);
}
});
//点击删除
ly_btn_yes.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {

            selection.setVisibility(View.VISIBLE);
            selection_no.setVisibility(View.INVISIBLE);
            selection.setVisibility(View.VISIBLE);
            selection_no.setVisibility(View.INVISIBLE);
            int a = type.size();//记录删除前数组长度
            int b = 0;
            for (int i = 0; i < a; i++) {
                if (type.get(i)) {//判断item被选中
                    if (b < adapter.getItemCount()) {//判断b是否大于当前数组长度，如果大于则结束循环
                        File file = adapter.getItem(b);//获取文件对象
                        if (file != null) {//判断当前是否为广告如果为广告则b++
                            file.delete();
                            type.remove(i);//数组中删除第i个数据
                            adapter.remove(b);//删除第b个item
                            Toast.makeText(PlayerListActivity.this, getResources().getString(R.string.delete_ly), Toast.LENGTH_SHORT).show();
                        } else {
                            b++;
                        }
                    } else {
                        break;
                    }
                } else {
                    //因为adapter删除后会刷新，每次删除都是第b个
                    b++;
                }
            }
            //记录删除后的数组长度
            int a1 = type.size();
            type.clear();//清空数组,并赋值false
            for (int i = 0; i < a1; i++) {
                type.put(i, false);
            }
            adapter.alter_state(0);
        }

    });

Recyclerview中添加
//chekbox点击事件
holder.delete.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
cheak_type.put(position, true);
} else {
cheak_type.put(position, false);
}
}
});
//根据state判断chekbox是否显示
if (state == 0) {
holder.delete.setVisibility(View.GONE);
} else {
holder.delete.setVisibility(View.VISIBLE);
}
//根据map的值判断chekbox是否选中
if (cheak_type.get(position) != null) {
if (cheak_type.get(position)) {
holder.delete.setChecked(true);
} else {
holder.delete.setChecked(false);
}
}
//当state=0时Checkbox不显示
public void alter_state(int i) {
if (i == 0) {
state = 0;
} else {
state = 1;
}
notifyDataSetChanged();
}

public void selectAll() {
    Set<Map.Entry<Integer, Boolean>> entries = cheak_type.entrySet();
    boolean should_all = true;
    for (Map.Entry<Integer, Boolean> entry : entries) {
        if (entry.getValue() != null) {
            entry.setValue(should_all);
        }
    }
    int a = cheak_type.size();
    if (cheak_type.size() <= getItemCount()) {
        int b = (getItemCount() + ad_number) - cheak_type.size();
        for (int i = 0; i < b; i++) {
            cheak_type.put(a + i, true);
        }
    }
    notifyDataSetChanged();
}

public void selectNoAll() {
    Set<Map.Entry<Integer, Boolean>> entries = cheak_type.entrySet();
    boolean should_all = false;
    for (Map.Entry<Integer, Boolean> entry : entries) {
        if (entry.getValue() != null) {
            entry.setValue(should_all);
        }
    }
    int a = cheak_type.size();
    if (cheak_type.size() <= getItemCount()) {
        int b = getItemCount() - cheak_type.size();
        for (int i = 0; i < b; i++) {
            cheak_type.put(a + i, false);
        }
    }
    notifyDataSetChanged();
}