Java RecyclerView中的多重选择？
您好，我正在尝试在Java RecyclerView中的多重选择？,java,android,android-recyclerview,Java,Android,Android Recyclerview,您好，我正在尝试在回收器视图中实现multi-select，以便在单击特定视图时显示图标，我已经尝试了以下代码，并且在该特定位置工作正常，但是还有其他几个视图也正在更新，因此请检查并让我知道我缺少了什么 以下是我的适配器代码： public class ContactsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ Context context; ArrayList<String> alCo
回收器视图中实现multi-select，以便在单击特定视图时显示图标，我已经尝试了以下代码，并且在该特定位置工作正常，但是还有其他几个视图也正在更新，因此请检查并让我知道我缺少了什么
以下是我的适配器代码：
public class ContactsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
Context context;
ArrayList<String> alContactName, alContactEmail, alContactNumber;
ArrayList<Boolean> alFromLinkedIn;
int mergeFlag=0;
private static SparseBooleanArray selectedItems;
ArrayList<Integer> alSelectedPositions;
public ContactsAdapter(Context context, ArrayList<String> alContactName, ArrayList<String> alContactEmail, ArrayList<String> alContactNumber, ArrayList<Boolean> alisFromLinkedIn) {
//Include one more variable for checking type i.e linked in or normal contact
super();
this.context = context;
this.alContactName = alContactName;
this.alContactEmail = alContactEmail;
this.alContactNumber = alContactNumber;
this.alFromLinkedIn = alisFromLinkedIn;
alSelectedPositions=new ArrayList<>();
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_merge_contact, parent, false);
return new ContactsHolder(view);
}
@Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
try {
((ContactsHolder) holder).relMain.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
alSelectedPositions.add(position);
notifyDataSetChanged();
}
});
if(alSelectedPositions.get(position)==position){
((ContactsHolder) holder).imgMerge.setVisibility(View.VISIBLE);
}
else {
((ContactsHolder) holder).imgMerge.setVisibility(View.GONE);
}
} catch (Exception e) {
e.printStackTrace();
}
}
公共类ContactsAdapter扩展了RecyclerView.Adapter{
语境；
ArrayList alContactName、alContactEmail、alContactNumber；
ArrayList alFromLinkedIn；
int mergeFlag=0；
专用静态SparseBooleanArray selectedItems；
ArrayList也可选择位置；
公共联系人适配器（上下文上下文、ArrayList alContactName、ArrayList alContactEmail、ArrayList alContactNumber、ArrayList alisFromLinkedIn）{
//包括一个以上用于检查类型的变量，即连接或正常接触
超级（）；
this.context=上下文；
this.alContactName=alContactName；
this.alContactEmail=alContactEmail；
this.alContactNumber=alContactNumber；
this.alFromLinkedIn=alisFromLinkedIn；
alSelectedPositions=新的ArrayList（）；
}
@凌驾
public RecyclerView.ViewHolder onCreateViewHolder（视图组父级，int-viewType）{
LayoutFlater充气机=LayoutFlater.from（上下文）；
View=LayoutFlater.from（parent.getContext（））.flate（R.layout.row\u merge\u contact，parent，false）；
返回新联系人文件夹（视图）；
}
@凌驾
public void onBindViewHolder（final RecyclerView.ViewHolder，int位置）{
试一试{
（（ContactsHolder）holder.relMain.setOnClickListener（新视图.OnClickListener（））{
@凌驾
公共void onClick（视图）{
也可选择职位。添加（职位）；
notifyDataSetChanged（）；
}
});
if（alSelectedPositions.get（position）==位置）{
（（ContactsHolder）保持架）.imgMerge.setVisibility（View.VISIBLE）；
}
否则{
（（ContactsHolder）holder.imgMerge.setVisibility（View.GONE）；
}
}捕获（例外e）{
e、 printStackTrace（）；
}
}
您必须做一些特定的事情：
- 初始化int类型数组（类型可以不同），并为其所有元素赋值0
int[] selectedPos = null;
public ContactsAdapter(Context context, ArrayList<String> alContactName, ArrayList<String> alContactEmail, ArrayList<String> alContactNumber, ArrayList<Boolean> alisFromLinkedIn) {
//Include one more variable for checking type i.e linked in or normal contact
super();
this.context = context;
this.alContactName = alContactName;
this.alContactEmail = alContactEmail;
this.alContactNumber = alContactNumber;
this.alFromLinkedIn = alisFromLinkedIn;
alSelectedPositions=new ArrayList<>();
for(int i = 0 ; i < alContactName.size() ; i++)
selectedPos[i] = 0;
}
最近，我不得不实现一个multi-selectRecyclerView
，下面我附加了一个简化的代码片段，以便以一种干净的方式实现RecyclerView
中的multi-select功能：
public class ItemAdapter extends RecyclerView.Adapter<ItemAdapter.ItemHolder> implements IMultiSelectableList<Item> {
boolean selectionMode = false;
HashSet<Item> selectedItems;
ArrayList<Item> mItems;
public ItemAdapter(ArrayList<Item> Items) {
super();
selectedItems = new HashSet<>();
mItems = Items;
}
public void enterSelectionModeWithItem(int selectedItemPosition){
if(selectedItemPosition >= 0 && selectedItemPosition < mItems.size())
selectedItems.add(mItems.get(selectedItemPosition));
selectionMode = true;
notifyDataSetChanged();
}
public void clearSelectionMode() {
selectionMode = false;
selectedItems.clear();
notifyDataSetChanged();
}
public class ItemHolder extends RecyclerView.ViewHolder{
ImageView mImage;
public ItemHolder(View itemView) {
super(itemView);
mImage = itemView.findViewById(R.id.image);
itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
if(!selectionMode){
int selectedPosition = getAdapterPosition();
Item selectedItem = mItems.get(selectedPosition);
enterSelectionModeWithItem(selectedItem);
return true;
}
return false;
}
});
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
int selectedPosition = getAdapterPosition();
Item selectedItem = mItems.get(selectedPosition);
//Capture Clicks in Selection Mode
if(selectionMode){
if(selectedItems.contains(selectedItem)){
selectedItems.remove(selectedItem);
mImage.setImageResource(R.drawable.ic_checkbox_blank_circle_outline_grey600_48dp);
} else {
selectedItems.add(selectedItem);
mImage.setImageResource(R.drawable.ic_checkbox_marked_circle_grey600_48dp);
}
}
}
});
}
public void setupView(Item item){
if(selectionMode){
if(selectedItems.contains(item)){
mImage.setImageResource(R.drawable.ic_checkbox_marked_circle_grey600_48dp);
} else {
mImage.setImageResource(R.drawable.ic_checkbox_blank_circle_outline_grey600_48dp);
}
}
}
@Override
public ItemAdapter.ItemHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cell_item, parent, false);
return new ItemHolder(view);
}
@Override
public void onBindViewHolder(ItemAdapter.ItemHolder holder, int position) {
holder.setupView(mItems.get(position));
}
@Override
public int getItemCount() {
return mItems != null ? mItems.size() : 0;
}
}
公共类ItemAdapter扩展了RecyclerView。适配器实现IMultiSelectableList{
布尔选择模式=假；
HashSet-selectedItems；
柱叶螨；
公共项适配器（ArrayList项）{
超级（）；
selectedItems=newhashset（）；
mItems=项目；
}
public void enter selectionmodewithitem（int-selectedItemPosition）{
如果（selectedItemPosition>=0&&selectedItemPosition
，我使用图像来显示选择，如Gmail应用程序，但可以随意使用任何适合您的内容（背景色、字体样式等）
我为一个简单的选择交互设计了一个回调接口，
public class ItemAdapter extends RecyclerView.Adapter<ItemAdapter.ItemHolder> implements IMultiSelectableList<Item> {
boolean selectionMode = false;
HashSet<Item> selectedItems;
ArrayList<Item> mItems;
public ItemAdapter(ArrayList<Item> Items) {
super();
selectedItems = new HashSet<>();
mItems = Items;
}
public void enterSelectionModeWithItem(int selectedItemPosition){
if(selectedItemPosition >= 0 && selectedItemPosition < mItems.size())
selectedItems.add(mItems.get(selectedItemPosition));
selectionMode = true;
notifyDataSetChanged();
}
public void clearSelectionMode() {
selectionMode = false;
selectedItems.clear();
notifyDataSetChanged();
}
public class ItemHolder extends RecyclerView.ViewHolder{
ImageView mImage;
public ItemHolder(View itemView) {
super(itemView);
mImage = itemView.findViewById(R.id.image);
itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
if(!selectionMode){
int selectedPosition = getAdapterPosition();
Item selectedItem = mItems.get(selectedPosition);
enterSelectionModeWithItem(selectedItem);
return true;
}
return false;
}
});
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
int selectedPosition = getAdapterPosition();
Item selectedItem = mItems.get(selectedPosition);
//Capture Clicks in Selection Mode
if(selectionMode){
if(selectedItems.contains(selectedItem)){
selectedItems.remove(selectedItem);
mImage.setImageResource(R.drawable.ic_checkbox_blank_circle_outline_grey600_48dp);
} else {
selectedItems.add(selectedItem);
mImage.setImageResource(R.drawable.ic_checkbox_marked_circle_grey600_48dp);
}
}
}
});
}
public void setupView(Item item){
if(selectionMode){
if(selectedItems.contains(item)){
mImage.setImageResource(R.drawable.ic_checkbox_marked_circle_grey600_48dp);
} else {
mImage.setImageResource(R.drawable.ic_checkbox_blank_circle_outline_grey600_48dp);
}
}
}
@Override
public ItemAdapter.ItemHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.cell_item, parent, false);
return new ItemHolder(view);
}
@Override
public void onBindViewHolder(ItemAdapter.ItemHolder holder, int position) {
holder.setupView(mItems.get(position));
}
@Override
public int getItemCount() {
return mItems != null ? mItems.size() : 0;
}
}
@Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
try {
((ContactsHolder) holder).relMain.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if(alSelectedPositions.size>0)
{
for(int i=0;i<a1SelectedPositions.size;i++)
{
//if you want to cleasr previous details of array
if(a1SelectedPositions.contains(position))
alSelectedPositions.remove(position);
else
alSelectedPositions.add(position);
}
}
else
{
alSelectedPositions.add(position);
notifyDataSetChanged();
}
});
//update the position on scroll
for(int i=0;i<a1SelectedPositions.size;i++)
{
if(alSelectedPositions.get(i)==position){
((ContactsHolder)holder).imgMerge.setVisibility(View.VISIBLE);
}
else {
((ContactsHolder) holder).imgMerge.setVisibility(View.GONE);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public ContactsHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_merge_contact, parent, false);
final ContactsHolder holder = new ContactsHolder(view);
view.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (holder.getAdapterPosition() != RecyclerView.NO_POSITION) {
mSelectedItemPosition = holder.getAdapterPosition();
//notifyItemChanged(holder.getAdapterPosition());
notifyDataSetChanged();
}
}
});
return holder;
}
@Override
public void onBindViewHolder(ContactsHolder holder, int position) {
try {
if (mSelectedItemPosition == position) {
if (mergeFlag != 1) {
holder.imgMerge.setVisibility(View.VISIBLE);
mergeFlag = 1;
selectdParentId = contactsModels.get(position).alContactIdList;
} else{
//holder.relDone.setVisibility(View.GONE);
if (!selectdParentId.equals(contactsModels.get(position).alContactIdList)) {
holder.relDone.setVisibility(View.VISIBLE);
alChildId.add(contactsModels.get(position).alContactIdList);
} else {
holder.imgMerge.setVisibility(View.VISIBLE);
}
}
} else {
holder.imgMerge.setVisibility(View.GONE);
holder.relDone.setVisibility(View.GONE);
}
}