Как настроить флажки в счетчике множественного выбора в Android?

Похоже, что селектор с флажками создается отдельно от обычной работы Spinner с помощью этого кода:

@Override
public boolean performClick() {
    AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
    builder.setMultiChoiceItems(
            items.toArray(new CharSequence[items.size()]), selected, this);
    builder.setPositiveButton(android.R.string.ok,
            new DialogInterface.OnClickListener() {

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            });
    builder.setOnCancelListener(this);
    builder.show();
    return true;
}

Поэтому для настройки вам придется настроить макет с несколькими вариантами выбора AlertDialog.

Вам просто нужно заменить

ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(),
            android.R.layout.simple_spinner_item,
            new String[] { spinnerText });

to

ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(),
            R.layout.your_row_item,
            new String[] { spinnerText });

Я также использовал класс multispinner и сделал настройку в соответствии с потребностями. Вот класс MultiSpinner.java

public class MultiSpinner extends Spinner implements DialogInterface.OnMultiChoiceClickListener, DialogInterface.OnCancelListener {

private List<String> items;
private List<GradeBean> mGradeBeanList = new ArrayList<GradeBean>();
private boolean[] selected;
private MultiSpinnerListener listener;
private String mGradeIds="";
private String mGrades="";
private MultiChoiceAdapter multiChoiceAdapter;
private AlertDialog alertDialog;
public MultiSpinner(Context context) {
    super(context);
}

public MultiSpinner(Context arg0, AttributeSet arg1) {
    super(arg0, arg1);
}

public MultiSpinner(Context arg0, AttributeSet arg1, int arg2) {
    super(arg0, arg1, arg2);
}

@Override
public void onClick(DialogInterface dialog, int which, boolean isChecked) {
    if (isChecked)
        selected[which] = true;
    else
        selected[which] = false;
}

@Override
public boolean performClick() {
    multiChoiceAdapter = new MultiChoiceAdapter(mGradeBeanList,selected);
    AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
    builder.setAdapter(multiChoiceAdapter,null);
    builder.setPositiveButton(android.R.string.ok,
            new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            });
    alertDialog = builder.create();
    ListView listView = alertDialog.getListView();
    listView.setAdapter(multiChoiceAdapter);
    listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            selected[position] = !selected[position];
            multiChoiceAdapter.notifyDataSetChanged();
        }
    });
    alertDialog.setOnCancelListener(this);
    alertDialog.show();
    return true;
}

public void setItems(List<GradeBean> gradeBeanList, int defaultSelected,MultiSpinnerListener listener) {
    mGradeBeanList.clear();
    Log.e("list",""+gradeBeanList);
    mGradeBeanList.addAll(gradeBeanList);
    this.listener = listener;
    items = new ArrayList<String>();
    // all selected by default
    selected = new boolean[mGradeBeanList.size()];
    for (int i = 0; i < selected.length; i++) {
        if (defaultSelected == i) {
            selected[i] = true;
        } else {
            selected[i] = false;
        }
    }
    for(int i= 0;i<mGradeBeanList.size();i++)
    {
        items.add(mGradeBeanList.get(i).getGradeName());
    }
    // all text on the spinner
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(), R.layout.row_spinner, new String[] { mGradeBeanList.get(defaultSelected).getGradeName()});
    setAdapter(adapter);
    performClick();
    alertDialog.cancel();
}


@Override
public void onCancel(DialogInterface dialog) {
    StringBuilder spinnerBuilder = new StringBuilder();
    StringBuilder gradeBuilder = new StringBuilder();

    for (int i = 0; i < items.size(); i++) {
        if (selected[i] == true) {
            spinnerBuilder.append(items.get(i));
            spinnerBuilder.append(", ");
            gradeBuilder.append(mGradeBeanList.get(i).getGradeId());
            gradeBuilder.append(", ");
        }
    }
    String spinnerText = "";
    if (spinnerBuilder.length() > 2) {
        spinnerText = spinnerBuilder.substring(0, spinnerBuilder.length() - 2).toString();
        mGrades = spinnerText;
    }
    if (gradeBuilder.length() > 2) {
        mGradeIds = gradeBuilder.substring(0, gradeBuilder.length() - 2).toString();
    }
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(),R.layout.row_spinner,new String[] { spinnerText });
    setAdapter(adapter);
    listener.onItemsSelected(selected);
}


public interface MultiSpinnerListener {
    public void onItemsSelected(boolean[] selected);
}

public String getGradeIds() {
    return mGradeIds;
}
public String getGrades() {
    return mGrades;
}

public void setItems(List<GradeBean> gradeBeanList,List<String> itemValues,String selectedList,MultiSpinnerListener listener) {
    mGradeBeanList.clear();
    Log.e("list",""+gradeBeanList);
    mGradeBeanList.addAll(gradeBeanList);
    this.listener = listener;
    items = new ArrayList<String>();

    for(int i= 0;i<mGradeBeanList.size();i++)
    {
        items.add(mGradeBeanList.get(i).getGradeName());
    }
    // Set false by default
    selected = new boolean[mGradeBeanList.size()];
    for (int j = 0; j < itemValues.size(); j++)
        selected[j] = false;

    String spinnerText = "";
    StringBuilder gradeBuilder= new StringBuilder();
    if (selectedList != null) {
        String[] selectedItems = selectedList.trim().split(",");
        for (int i = 0; i < selectedItems.length; i++)
            for (int j = 0; j < mGradeBeanList.size(); j++)
                if (selectedItems[i].trim().equals(mGradeBeanList.get(j).getGradeName())) {
                    selected[j] = true;
                    gradeBuilder.append(mGradeBeanList.get(j).getGradeId());
                    gradeBuilder.append(", ");
                    spinnerText += (spinnerText.equals("")?"":", ") + items.get(j);
                    break;
                }
    }
    mGrades = spinnerText;
    if (gradeBuilder.length() > 2) {
        mGradeIds = gradeBuilder.substring(0, gradeBuilder.length() - 2).toString();
    }
    // Text for the spinner
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(getContext(),R.layout.row_spinner, new String[] { spinnerText });
    setAdapter(adapter);
   }
}

и row_spinner.xml

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
 android:id="@+id/tv_name" 
 style="@style/style_tv_normal_fill" 
 android:singleLine="true" 
 android:text="TEXT1"
 android:padding="@dimen/d_tv_row_spinner_padding"/>

вы можете изменить код в соответствии с вашими потребностями.