Question

我正在使用带有复选框的listview获取手机通讯录。我使用了link中给出的说明。如果我想选择一些联系人，代码工作正常。现在我想在活动

中添加“全选”复选框

// Logcat
FATAL EXCEPTION: main
Process: com.sam.afrikk, PID: 10628
java.lang.IndexOutOfBoundsException: Invalid index 0, size is 0
at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
at java.util.ArrayList.get(ArrayList.java:308)
at com.sam.afrikk.ContactsPickerActivity$1.onCheckedChanged(ContactsPickerActivity.java:54)
at android.widget.CompoundButton.setChecked(CompoundButton.java:156)
at android.widget.CompoundButton.toggle(CompoundButton.java:115)
at android.widget.CompoundButton.performClick(CompoundButton.java:120)
at android.view.View$PerformClick.run(View.java:21534)
at android.os.Handler.handleCallback(Handler.java:815)
at android.os.Handler.dispatchMessage(Handler.java:104)
at android.os.Looper.loop(Looper.java:207)

但我得到了IndexOutOfBoundsException。

public class ContactsList{

    public ArrayList<Contact> contactArrayList;

    ContactsList(){

        contactArrayList = new ArrayList<Contact>();
    }



    public int getCount(){

        return contactArrayList.size();
    }

    public void addContact(Contact contact){
        contactArrayList.add(contact);
    }



    public  void removeContact(Contact contact){
        contactArrayList.remove(contact);
    }

    public Contact getContact(int id){

        for(int i=0;i<this.getCount();i++){
            if(Integer.parseInt(contactArrayList.get(i).id)==id)
                return contactArrayList.get(i);
        }

        return null;
    }




}

public class ContactsListAdapter extends BaseAdapter {

    Context context;
    ContactsList contactsList,filteredContactsList,selectedContactsList;
    String filterContactName;

    ContactsListAdapter(Context context, ContactsList contactsList){

        super();
        this.context = context;
        this.contactsList = contactsList;
        this.filteredContactsList=new ContactsList();
        this.selectedContactsList = new ContactsList();
        this.filterContactName = "";
    }

    public void filter(String filterContactName){



        filteredContactsList.contactArrayList.clear();

        if(filterContactName.isEmpty() || filterContactName.length()<1){
            filteredContactsList.contactArrayList.addAll(contactsList.contactArrayList);
            this.filterContactName = "";

        }
        else {
            this.filterContactName = filterContactName.toLowerCase().trim();
            for (int i = 0; i < contactsList.contactArrayList.size(); i++) {

                if (contactsList.contactArrayList.get(i).name.toLowerCase().contains(filterContactName))
                    filteredContactsList.addContact(contactsList.contactArrayList.get(i));
            }
        }
        notifyDataSetChanged();

    }

    public void addContacts(ArrayList<Contact> contacts){
        this.contactsList.contactArrayList.addAll(contacts);
        this.filter(this.filterContactName);

    }

    @Override
    public int getCount() {
        return filteredContactsList.getCount();
    }

    @Override
    public Contact getItem(int position) {
        return filteredContactsList.contactArrayList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return Long.parseLong(this.getItem(position).id);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        ViewHolder viewHolder;

        if(convertView==null){
            LayoutInflater inflater = ((Activity)context).getLayoutInflater();

            convertView = inflater.inflate(R.layout.contact_item, parent, false);

            viewHolder = new ViewHolder();
            viewHolder.chkContact = (CheckBox) convertView.findViewById(R.id.chk_contact);
            convertView.setTag(viewHolder);

        }else {
            viewHolder = (ViewHolder) convertView.getTag();
        }

        viewHolder.chkContact.setText(this.filteredContactsList.contactArrayList.get(position).toString());
        viewHolder.chkContact.setId(Integer.parseInt(this.filteredContactsList.contactArrayList.get(position).id));
        viewHolder.chkContact.setChecked(alreadySelected(filteredContactsList.contactArrayList.get(position)));

        viewHolder.chkContact.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                Contact contact = filteredContactsList.getContact(buttonView.getId());

                if(contact!=null && isChecked && !alreadySelected(contact)){
                    selectedContactsList.addContact(contact);
                }
                else if(contact!=null && !isChecked){
                    selectedContactsList.removeContact(contact);
                }
            }
        });

        return convertView;
    }

    public boolean alreadySelected(Contact contact)
    {
        if(this.selectedContactsList.getContact(Integer.parseInt(contact.id))!=null)
            return true;

        return false;
    }


    public static class ViewHolder{

        CheckBox chkContact;
    }
}

public class ContactsPickerActivity extends AppCompatActivity {

    ListView contactsChooser;
    Button btnDone;
    TextView txtLoadInfo;
    ContactsListAdapter contactsListAdapter;
    ContactsLoader contactsLoader;
    CheckBox selectAll;
    Contact contact;
    ContactsList contactsList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_contacts_picker);

        contactsChooser = (ListView) findViewById(R.id.lst_contacts_chooser);
        btnDone = (Button) findViewById(R.id.btn_done);
        txtLoadInfo = (TextView) findViewById(R.id.txt_load_progress);
        selectAll = (CheckBox)findViewById(R.id.selectAll);

        contactsListAdapter = new ContactsListAdapter(this,new ContactsList());

        contactsChooser.setAdapter(contactsListAdapter);


        loadContacts("");

        selectAll.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                contactsList = new ContactsList();


                if(isChecked){
                    selectAll.setText("Unselect All");
					//HERE I"M GETTING EXCEPTION
                    for (int i=0;i<contactsListAdapter.getCount();i++){
                        contact = contactsListAdapter.selectedContactsList.contactArrayList.get(i);
                        contactsListAdapter.selectedContactsList.addContact(contact);
                    }
                }else{
                    selectAll.setText("Select All");
                    for (int i=0;i<contactsListAdapter.getCount();i++){
                        contact = contactsListAdapter.selectedContactsList.contactArrayList.get(i);
                        contactsListAdapter.selectedContactsList.removeContact(contact);
                    }

                }
            }
        });

        btnDone.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if(contactsListAdapter.selectedContactsList.contactArrayList.isEmpty()){
                    setResult(RESULT_CANCELED);
                }
                else{

                    Intent resultIntent = new Intent();

                    resultIntent.putParcelableArrayListExtra("SelectedContacts", contactsListAdapter.selectedContactsList.contactArrayList);
                    setResult(RESULT_OK,resultIntent);

                }
                finish();

            }
        });
    }



    private void loadContacts(String filter){

        if(contactsLoader!=null && contactsLoader.getStatus()!= AsyncTask.Status.FINISHED){
            try{
                contactsLoader.cancel(true);
            }catch (Exception e){

            }
        }
        if(filter==null) filter="";

        try{
            //Running AsyncLoader with adapter and  filter
            contactsLoader = new ContactsLoader(this,contactsListAdapter);
            contactsLoader.txtProgress = txtLoadInfo;
            contactsLoader.execute(filter);
        }catch(Exception e){
            e.printStackTrace();
        }
    }




}

Answer 1

那里有两个问题：

您将遍历整个联系人列表，而不是仅覆盖所选联系人列表：（我还将你的迭代器从for循环改为数组迭代器，这使代码更具可读性）
在取消选择的区块中，您正在拨打addContact而不是removeContact

Array<Contact> selectedContactsArray = contactsListAdapter.selectedContactsList.contactArrayList;
for (Contact contact : selectedContactsArray) {
   contactsListAdapter.selectedContactsList.removeContact(contact);
}

使用复选框

1 个答案: