Java 如何从适配器访问活动的arrayList?
我在适配器中创建了一个方法。在这个方法中,我有一个arraylist。我想在活动中访问此arrayList。我该怎么做 适配器:Java 如何从适配器访问活动的arrayList?,java,android,android-activity,arraylist,adapter,Java,Android,Android Activity,Arraylist,Adapter,我在适配器中创建了一个方法。在这个方法中,我有一个arraylist。我想在活动中访问此arrayList。我该怎么做 适配器: public class InviteAdapter extends RecyclerView.Adapter<InviteAdapter.MyViewHolder> { private ArrayList<Contact> contactArrayList; private Context mContext;
public class InviteAdapter extends RecyclerView.Adapter<InviteAdapter.MyViewHolder> {
private ArrayList<Contact> contactArrayList;
private Context mContext;
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView name;
private CheckBox checkBox;
public MyViewHolder(View view) {
super(view);
name = (TextView) view.findViewById(R.id.textContactName);
checkBox = (CheckBox) view.findViewById(R.id.checkBox);
}
}
public InviteAdapter(Context context, ArrayList<Contact> contactArrayList) {
this.contactArrayList = contactArrayList;
this.mContext = context;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.invite_contact_item, parent, false);
return new MyViewHolder(itemView);
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
Contact contact = contactArrayList.get(position);
holder.name.setText(contact.getmFullName());
holder.checkBox.setChecked(contact.getSelected());
}
@Override
public int getItemCount() {
return contactArrayList.size();
}
public void toggleContactsSelection( boolean isSelected ) {
for( Contact contact : contactArrayList ) {
contact.setSelected(isSelected);
invite(contact);
}
notifyDataSetChanged(); // OR you can use notifyItemRangeChanged - which ever suits your needs
}
public void invite(Contact contact)
{
ArrayList<Invitation> invitationArrayList = new ArrayList<>();
SharedPreferences sharedpreferences = mContext.getSharedPreferences("UserId", Context.MODE_PRIVATE);
String mUserId = sharedpreferences.getString("userId","");
DateFormat df = new SimpleDateFormat("EEE, d MMM yyyy, HH:mm", Locale.ENGLISH);
String date = df.format(Calendar.getInstance().getTime());
Invitation invitation = new Invitation();
invitation.setSender_id(mUserId);
invitation.setDate(date);
invitation.setInvitee_no(contact.getmMobileNo());
invitation.setStatus("0");
invitation.setUser_name(contact.getmUserName());
invitationArrayList.add(invitation);
}
}
公共类InviteAdapter扩展了RecyclerView.Adapter{
私人ArrayList联系人ArrayList;
私有上下文;
公共类MyViewHolder扩展了RecyclerView.ViewHolder{
公共文本视图名称;
私有复选框;
公共MyViewHolder(视图){
超级(视图);
name=(TextView)view.findViewById(R.id.textContactName);
checkBox=(checkBox)view.findviewbyd(R.id.checkBox);
}
}
公共适配器(上下文上下文,ArrayList contactArrayList){
this.contactArrayList=contactArrayList;
this.mContext=上下文;
}
@凌驾
公共MyViewHolder onCreateViewHolder(视图组父级,int-viewType){
View itemView=LayoutInflater.from(parent.getContext())
.充气(R.layout.invite\u contact\u item,parent,false);
返回新的MyViewHolder(itemView);
}
@凌驾
公共无效onBindViewHolder(MyViewHolder,int位置){
Contact Contact=contactArrayList.get(位置);
holder.name.setText(contact.getmFullName());
holder.checkBox.setChecked(contact.getSelected());
}
@凌驾
public int getItemCount(){
返回contactArrayList.size();
}
公共无效切换联系人选择(布尔值为已选择){
用于(联系人:contactArrayList){
联系人:setSelected(isSelected);
邀请(联系);
}
notifyDataSetChanged();//或者您可以使用notifyItemRangeChanged-这非常适合您的需要
}
公开作废邀请(联系人)
{
ArrayList invitationArrayList=新建ArrayList();
SharedReferences SharedReferences=mContext.getSharedReferences(“UserId”,Context.MODE\u PRIVATE);
String mUserId=sharedpreferences.getString(“userId”,”);
DateFormat df=新的SimpleDateFormat(“EEE,d MMM yyyy,HH:mm”,Locale.ENGLISH);
字符串date=df.format(Calendar.getInstance().getTime());
邀请=新邀请();
邀请函:setSender_id(mUserId);
邀请。设定日期(日期);
invitation.setInvitee_no(contact.getmMobileNo());
邀请。设置状态(“0”);
invitation.setUser_name(contact.getmUserName());
邀请列表。添加(邀请);
}
}
我想从适配器的invite方法访问邀请数组列表
活动:
public class InviteContactsActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private InviteAdapter mAdapter;
private ArrayList<Contact> mContactList;
private ContactTableHelper mContactDb;
private ArrayList<Invitation> invitationArrayList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_invite_contacts);
final ImageView selectAll = (ImageView)findViewById(R.id.imageMenu);
selectAll.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
PopupMenu popup = new PopupMenu(InviteContactsActivity.this,selectAll);
popup.getMenuInflater().inflate(R.menu.pop_up_menu, popup.getMenu());
popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
public boolean onMenuItemClick(MenuItem item) {
mAdapter.toggleContactsSelection(true); //Selects all contacts
return true;
}
});
popup.show();
}
});
ImageView sendInvites = (ImageView)findViewById(R.id.imageSelect);
sendInvites.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Gson gson=new Gson();
String toServer = gson.toJson(
Collections.singletonMap("invitations", invitationArrayList)
);
new SendMultipleInvitesAsyncTask(InviteContactsActivity.this).execute(toServer);
}
});
mContactDb = new ContactTableHelper(InviteContactsActivity.this);
mContactList = mContactDb.getAllContacts();
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
mRecyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(InviteContactsActivity.this);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));
mRecyclerView.setItemAnimator(new DefaultItemAnimator());
mAdapter = new InviteAdapter(InviteContactsActivity.this, mContactList);
mRecyclerView.setAdapter(mAdapter);
}
}
public class InviteContactsActivity扩展了AppCompative活动{
私人回收视图mRecyclerView;
私有适配器mAdapter;
私有ArrayList mContactList;
私有ContactTableHelper mContactDb;
私人ArrayList邀请赛ArrayList;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity\u invite\u contacts);
最终图像视图选择All=(图像视图)findViewById(R.id.imageMenu);
selectAll.setOnClickListener(新建视图.OnClickListener(){
@凌驾
公共void onClick(视图){
PopupMenu popup=新建PopupMenu(邀请联系人活动,选择All);
popup.getMenuInflater().充气(R.menu.pop_up_menu,popup.getMenu());
setOnMenuItemClickListener(新的PopupMenu.OnMenuItemClickListener(){
公共布尔onMenuItemClick(菜单项){
mAdapter.toggleContactsSelection(true);//选择所有联系人
返回true;
}
});
popup.show();
}
});
ImageView SendInvests=(ImageView)findViewById(R.id.imageSelect);
SendInvests.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图){
Gson Gson=新的Gson();
字符串toServer=gson.toJson(
收藏。单件地图(“邀请”,邀请列表)
);
新建SendMultipleInvitesAsyncTask(InviteContactsActivity.this).execute(toServer);
}
});
mContactDb=新的ContactTableHelper(InviteContactsActivity.this);
mContactList=mContactDb.getAllContacts();
mRecyclerView=(RecyclerView)findViewById(R.id.recycler\u视图);
mRecyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager mLayoutManager=新建LinearLayoutManager(InviteContactsActivity.this);
mRecyclerView.setLayoutManager(mllayoutmanager);
mRecyclerView.addItemDecoration(新的DividerItemDecoration(这个,LinearLayoutManager.VERTICAL));
setItemAnimator(新的DefaultItemAnimator());
mAdapter=newinviteadapter(InviteContactsActivity.this,mContactList);
mRecyclerView.setAdapter(mAdapter);
}
}
我想从sendInvite图像视图的onClickListener适配器获取邀请arraylist
我该怎么做?谢谢..在适配器中编写一个get方法,然后从活动中调用它
public ArrayList<Object> getArrayList(){
return yourArrayList;
}
public ArrayList getArrayList(){
返回您的ArrayList;
}
在您的活动中,您可以得到如下内容,
yourAdapterObject.getArrayList()代码>将ivitearraylist创建为公共列表,并通过adpater在活动中访问
ArrayList<Invitation> invitationArrayList = new ArrayList<>();
public void invite(Contact contact)
{
SharedPreferences sharedpreferences = mContext.getSharedPreferences("UserId", Context.MODE_PRIVATE);
String mUserId = sharedpreferences.getString("userId","");
DateFormat df = new SimpleDateFormat("EEE, d MMM yyyy, HH:mm", Locale.ENGLISH);
String date = df.format(Calendar.getInstance().getTime());
Invitation invitation = new Invitation();
invitation.setSender_id(mUserId);
invitation.setDate(date);
invitation.setInvitee_no(contact.getmMobileNo());
invitation.setStatus("0");
invitation.setUser_name(contact.getmUserName());
invitationArrayList.add(invitation);
}
这可能会对您有所帮助:)
快乐编码:)您还可以使用该接口将数据从adpater类发送到活动。
下面的链接对其进行了漂亮的描述
在适配器内公开arraylist,并在执行onclick时通过适配器对象访问arraylist。在这种方法中,我有一个arraylist
。否。该arraylist在适配器类中。像
ImageView sendInvites = (ImageView)findViewById(R.id.imageSelect);
sendInvites.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Gson gson=new Gson();
String toServer = gson.toJson(
Collections.singletonMap("invitations", mAdpater.invitationArrayList)
);
new SendMultipleInvitesAsyncTask(InviteContactsActivity.this).execute(toServer);
}
});