Android 用于ArrayAdapter的getPositionForSection和getSectionForPosition和getSections方法_Android

Android 用于ArrayAdapter的getPositionForSection和getSectionForPosition和getSections方法

android

Android 用于ArrayAdapter的getPositionForSection和getSectionForPosition和getSections方法,android,Android,解释getPositionForSection（int）和getSectionForPosition（int）和getSections（）的用法ArrayAdapter 我得到了一个很好的解释谢谢 Charsequence alphabets = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; 这里创建新的字母索引器 AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex,

解释

getPositionForSection（int）

和

getSectionForPosition（int）

和

getSections（）的用法ArrayAdapter

我得到了一个很好的解释
谢谢
Charsequence alphabets = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

这里
创建新的字母索引器
AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, alphabets);

String[] sections = (String[]) alphabetIndexer.getSections();

public abstract class SectionedListAdapter extends ResourceCursorAdapter {

private SparseIntArray sections;
private SparseIntArray cursorPositions;
private Context mContext;
private int sortedColumnIndex;

private static final int NORMAL_LIST_VIEW = 0;
private static final int SECTION_LIST_VIEW = 1;
private static final int NULL_LIST_VIEW = 2;

public SectionedListAdapter(Context context, int layout, Cursor c,
                            boolean autoRequery, int sortedColumnIndex, int defaultBitmapResId) {
    super(context, layout, c, autoRequery);
    this.mContext = context;
    this.sortedColumnIndex = sortedColumnIndex;
    setSortedCursorColumn(c);
}

public void setSortedCursorColumn(Cursor cursor){
    if (cursor == null){
        return;
    }
    AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    sections = new SparseIntArray();
    int m=0;
    int t = 'A';
    for (int i=0; i < 26; i++){
        if ((i+1) < 26) {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i + 1);
            if (temp != position){
                sections.put(position + m, t+i);
                m++;
            }
        } else {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i-1);
            if (position != temp){
                sections.put(position + m, t+i);
            }
        }
    }
    int temp = 0;
    cursorPositions = new SparseIntArray();
    for (int i=0; i<cursor.getCount() + sections.size(); i++){
        if (sections.get(i, -1) != -1){
            temp ++;
            cursorPositions.put(i, -1);
        } else {
            cursorPositions.put(i, i - temp);
        }
    }
}

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (getItemViewType(position) == NORMAL_LIST_VIEW){
        if (view == null){
            view = newView(mContext, getCursor(), parent);
        }
        getCursor().moveToPosition(cursorPositions.get(position));
        bindView(view, mContext, getCursor(), position);
    } else if (getItemViewType(position) == SECTION_LIST_VIEW) {
        if (view == null){
            view = newSectionView(mContext, getCursor(), parent);
        }
        bindSectionView(view, mContext, (char)sections.get(position));
    } else {
        if (view == null){
        } else {
            view = new ViewStub(mContext);
        }
    }
    return view;
}

public abstract View newSectionView(Context context, Cursor cursor, ViewGroup parent);

public abstract void bindSectionView(View view, Context context, char text);

public abstract void bindView(View view, Context context, Cursor cursor, int position);

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEnabled(int position) {
    return cursorPositions.get(position) >= 0;
}

@Override
public int getItemViewType(int position) {
    if (cursorPositions.get(position) >= 0){
        return NORMAL_LIST_VIEW;
    }else if (cursorPositions.get(position) == -1){
        return SECTION_LIST_VIEW;
    } else {
        return NULL_LIST_VIEW;
    }
}

@Override
public int getViewTypeCount() {
    return 3;
}

private void putCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition) {
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(position));
        cursorPositions.put(actualPosition, -position);
    }
}

private void removeCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition){
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(-position));
        cursorPositions.put(actualPosition, position);
    }
}

@Override
public int getCount() {
    return cursorPositions == null ? 0 : cursorPositions.size();
}

public SparseIntArray getSections() {
    return sections;
}

public SparseIntArray getCursorPositions() {
    return cursorPositions;
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    //do nothing here
}

@Override
public Cursor swapCursor(Cursor newCursor) {
    return super.swapCursor(newCursor);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void changeCursor(Cursor cursor) {
    setSortedCursorColumn(cursor);
    super.changeCursor(cursor);
}
}

getSections（）检索提供给字母索引器的字母表的字符串[]
AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, alphabets);

String[] sections = (String[]) alphabetIndexer.getSections();

public abstract class SectionedListAdapter extends ResourceCursorAdapter {

private SparseIntArray sections;
private SparseIntArray cursorPositions;
private Context mContext;
private int sortedColumnIndex;

private static final int NORMAL_LIST_VIEW = 0;
private static final int SECTION_LIST_VIEW = 1;
private static final int NULL_LIST_VIEW = 2;

public SectionedListAdapter(Context context, int layout, Cursor c,
                            boolean autoRequery, int sortedColumnIndex, int defaultBitmapResId) {
    super(context, layout, c, autoRequery);
    this.mContext = context;
    this.sortedColumnIndex = sortedColumnIndex;
    setSortedCursorColumn(c);
}

public void setSortedCursorColumn(Cursor cursor){
    if (cursor == null){
        return;
    }
    AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    sections = new SparseIntArray();
    int m=0;
    int t = 'A';
    for (int i=0; i < 26; i++){
        if ((i+1) < 26) {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i + 1);
            if (temp != position){
                sections.put(position + m, t+i);
                m++;
            }
        } else {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i-1);
            if (position != temp){
                sections.put(position + m, t+i);
            }
        }
    }
    int temp = 0;
    cursorPositions = new SparseIntArray();
    for (int i=0; i<cursor.getCount() + sections.size(); i++){
        if (sections.get(i, -1) != -1){
            temp ++;
            cursorPositions.put(i, -1);
        } else {
            cursorPositions.put(i, i - temp);
        }
    }
}

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (getItemViewType(position) == NORMAL_LIST_VIEW){
        if (view == null){
            view = newView(mContext, getCursor(), parent);
        }
        getCursor().moveToPosition(cursorPositions.get(position));
        bindView(view, mContext, getCursor(), position);
    } else if (getItemViewType(position) == SECTION_LIST_VIEW) {
        if (view == null){
            view = newSectionView(mContext, getCursor(), parent);
        }
        bindSectionView(view, mContext, (char)sections.get(position));
    } else {
        if (view == null){
        } else {
            view = new ViewStub(mContext);
        }
    }
    return view;
}

public abstract View newSectionView(Context context, Cursor cursor, ViewGroup parent);

public abstract void bindSectionView(View view, Context context, char text);

public abstract void bindView(View view, Context context, Cursor cursor, int position);

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEnabled(int position) {
    return cursorPositions.get(position) >= 0;
}

@Override
public int getItemViewType(int position) {
    if (cursorPositions.get(position) >= 0){
        return NORMAL_LIST_VIEW;
    }else if (cursorPositions.get(position) == -1){
        return SECTION_LIST_VIEW;
    } else {
        return NULL_LIST_VIEW;
    }
}

@Override
public int getViewTypeCount() {
    return 3;
}

private void putCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition) {
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(position));
        cursorPositions.put(actualPosition, -position);
    }
}

private void removeCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition){
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(-position));
        cursorPositions.put(actualPosition, position);
    }
}

@Override
public int getCount() {
    return cursorPositions == null ? 0 : cursorPositions.size();
}

public SparseIntArray getSections() {
    return sections;
}

public SparseIntArray getCursorPositions() {
    return cursorPositions;
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    //do nothing here
}

@Override
public Cursor swapCursor(Cursor newCursor) {
    return super.swapCursor(newCursor);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void changeCursor(Cursor cursor) {
    setSortedCursorColumn(cursor);
    super.changeCursor(cursor);
}
}

getSectionForPosition（position）检索当前位置的节
考虑给定的情况
position  Data             getSectionForPosition(position)
________  _________            __________

   0      Ajdhfj j             0
   1      Aadf hdsf            0
   2      Ajfkldsahf           0
   3      Asdhfa df            0
   4      Badhf                1
   5      Bdfj sadif           1
   6      Bghoi ij             1
   7      Bjkojg o             1
   8      Cadj fkljsdf         2
   9      Cgjds kfja           2
   10     Cn khdfaj            2
   11     Cph iohsdf           2
   12     Czjfa sh             2
   13     Dfgoa hjoifaj        3
   14     Dzfjdak sfh          3
   15     Fhf adhf             5
   16     Zdfh ajdf            25

获取该职位的部门
String section = sections[getSectionForPosition(position)];

getPositionForSection（section）检索数据从该节开始的第一个位置
section      getPositionForSection(section)
_________    ____________________
0            0
1            4
2            8
3            13
4            13
5            15
6            15
7            15
8            15
.            .
.            .
.            .
23           15
24           15          
25           16

希望这对你有帮助
使用字母索引器的示例
AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, alphabets);

String[] sections = (String[]) alphabetIndexer.getSections();

public abstract class SectionedListAdapter extends ResourceCursorAdapter {

private SparseIntArray sections;
private SparseIntArray cursorPositions;
private Context mContext;
private int sortedColumnIndex;

private static final int NORMAL_LIST_VIEW = 0;
private static final int SECTION_LIST_VIEW = 1;
private static final int NULL_LIST_VIEW = 2;

public SectionedListAdapter(Context context, int layout, Cursor c,
                            boolean autoRequery, int sortedColumnIndex, int defaultBitmapResId) {
    super(context, layout, c, autoRequery);
    this.mContext = context;
    this.sortedColumnIndex = sortedColumnIndex;
    setSortedCursorColumn(c);
}

public void setSortedCursorColumn(Cursor cursor){
    if (cursor == null){
        return;
    }
    AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    sections = new SparseIntArray();
    int m=0;
    int t = 'A';
    for (int i=0; i < 26; i++){
        if ((i+1) < 26) {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i + 1);
            if (temp != position){
                sections.put(position + m, t+i);
                m++;
            }
        } else {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i-1);
            if (position != temp){
                sections.put(position + m, t+i);
            }
        }
    }
    int temp = 0;
    cursorPositions = new SparseIntArray();
    for (int i=0; i<cursor.getCount() + sections.size(); i++){
        if (sections.get(i, -1) != -1){
            temp ++;
            cursorPositions.put(i, -1);
        } else {
            cursorPositions.put(i, i - temp);
        }
    }
}

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (getItemViewType(position) == NORMAL_LIST_VIEW){
        if (view == null){
            view = newView(mContext, getCursor(), parent);
        }
        getCursor().moveToPosition(cursorPositions.get(position));
        bindView(view, mContext, getCursor(), position);
    } else if (getItemViewType(position) == SECTION_LIST_VIEW) {
        if (view == null){
            view = newSectionView(mContext, getCursor(), parent);
        }
        bindSectionView(view, mContext, (char)sections.get(position));
    } else {
        if (view == null){
        } else {
            view = new ViewStub(mContext);
        }
    }
    return view;
}

public abstract View newSectionView(Context context, Cursor cursor, ViewGroup parent);

public abstract void bindSectionView(View view, Context context, char text);

public abstract void bindView(View view, Context context, Cursor cursor, int position);

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEnabled(int position) {
    return cursorPositions.get(position) >= 0;
}

@Override
public int getItemViewType(int position) {
    if (cursorPositions.get(position) >= 0){
        return NORMAL_LIST_VIEW;
    }else if (cursorPositions.get(position) == -1){
        return SECTION_LIST_VIEW;
    } else {
        return NULL_LIST_VIEW;
    }
}

@Override
public int getViewTypeCount() {
    return 3;
}

private void putCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition) {
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(position));
        cursorPositions.put(actualPosition, -position);
    }
}

private void removeCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition){
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(-position));
        cursorPositions.put(actualPosition, position);
    }
}

@Override
public int getCount() {
    return cursorPositions == null ? 0 : cursorPositions.size();
}

public SparseIntArray getSections() {
    return sections;
}

public SparseIntArray getCursorPositions() {
    return cursorPositions;
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    //do nothing here
}

@Override
public Cursor swapCursor(Cursor newCursor) {
    return super.swapCursor(newCursor);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void changeCursor(Cursor cursor) {
    setSortedCursorColumn(cursor);
    super.changeCursor(cursor);
}
}

公共抽象类SectionListAdapter扩展了ResourceCursorAdapter{
私人SparseIntArray路段；
私人SparseIntArray光标位置；
私有上下文；
私有int-sortedColumnIndex；
私有静态最终int正常列表视图=0；
私有静态最终整型部分列表视图=1；
私有静态final int NULL_LIST_VIEW=2；
公共分区ListAdapter（上下文上下文、int布局、游标c、，
布尔自动请求，int-sortedColumnIndex，int-defaultBitmapResId）{
超级（上下文、布局、c、自动请求）；
this.mContext=上下文；
this.sortedColumnIndex=sortedColumnIndex；
setSortedCursorColumn（c）；
}
public void setSortedCursorColumn（光标）{
if（游标==null）{
返回；
}
字母索引器字母索引器=新的字母索引器（光标，分类列索引，“ABCDEFGHIJKLMNOPQRSTUVWXYZ”）；
截面=新SparseIntArray（）；
int m=0；
int t='A'；
对于（int i=0；i<26；i++）{
如果（（i+1）<26）{
int position=字母索引器。getPositionForSection（i）；
int temp=字母索引器getPositionForSection（i+1）；
如果（温度！=位置）{
放置（位置+m，t+i）；
m++；
}
}否则{
int position=字母索引器。getPositionForSection（i）；
int temp=字母索引器getPositionForSection（i-1）；
如果（位置！=温度）{
放置（位置+m，t+i）；
}
}
}
内部温度=0；
cursorPositions=新SparseIntArray（）；
对于（int i=0；i=0；
}
@凌驾
public int getItemViewType（int位置）{
if（cursorPositions.get（position）>=0）{
返回正常列表视图；
}else if（cursorPositions.get（position）=-1）{
返回节列表视图；
}否则{
返回空的列表视图；
}
}
@凌驾
public int getViewTypeCount（）{
返回3；
}
私有void putCursorExclusion（int位置，布尔值isActualPosition）{
如果（isActualPosition）{
放置（位置，-cursorPositions.get（位置））；
}否则{
int actualPosition=cursorPositions.keyAt（cursorPositions.indexOfValue（position））；
放置（实际位置，-位置）；
}
}
私有void removeCursorExclusion（int位置，布尔值isActualPosition）{
如果（isActualPosition）{
放置（位置，-cursorPositions.get（位置））；
}否则{
int actualPosition=cursorPositions.keyAt（cursorPositions.indexOfValue（-position））；
光标位置。放置（实际位置、位置）；
}
}
@凌驾
public int getCount（）{
返回cursorPositions==null？0:cursorPositions.size（）；
}
公共SparseIntArray getSections（）{
回流段；
}
公共SparseIntArray getCursorPositions（）{
返回光标位置；
}
@凌驾
公共void bindView（视图、上下文上下文、光标）{
//在这里什么也不做
}
@凌驾
公共游标交换游标（游标新建游标）{
返回super.swapCursor（newCursor）；
}
@凌驾
public void notifyDataSetChanged（）{
super.notifyDataSetChanged（）；
}
@凌驾
公共void changeCursor（游标）{
setSortedCursorColumn（光标）；
super.changeCursor（游标）；
}
}

要使用它，只需创建一个新类extensedSectionListAdapter，然后提供所需的详细信息
这里
创建新的字母索引器
AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, alphabets);

String[] sections = (String[]) alphabetIndexer.getSections();

public abstract class SectionedListAdapter extends ResourceCursorAdapter {

private SparseIntArray sections;
private SparseIntArray cursorPositions;
private Context mContext;
private int sortedColumnIndex;

private static final int NORMAL_LIST_VIEW = 0;
private static final int SECTION_LIST_VIEW = 1;
private static final int NULL_LIST_VIEW = 2;

public SectionedListAdapter(Context context, int layout, Cursor c,
                            boolean autoRequery, int sortedColumnIndex, int defaultBitmapResId) {
    super(context, layout, c, autoRequery);
    this.mContext = context;
    this.sortedColumnIndex = sortedColumnIndex;
    setSortedCursorColumn(c);
}

public void setSortedCursorColumn(Cursor cursor){
    if (cursor == null){
        return;
    }
    AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    sections = new SparseIntArray();
    int m=0;
    int t = 'A';
    for (int i=0; i < 26; i++){
        if ((i+1) < 26) {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i + 1);
            if (temp != position){
                sections.put(position + m, t+i);
                m++;
            }
        } else {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i-1);
            if (position != temp){
                sections.put(position + m, t+i);
            }
        }
    }
    int temp = 0;
    cursorPositions = new SparseIntArray();
    for (int i=0; i<cursor.getCount() + sections.size(); i++){
        if (sections.get(i, -1) != -1){
            temp ++;
            cursorPositions.put(i, -1);
        } else {
            cursorPositions.put(i, i - temp);
        }
    }
}

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (getItemViewType(position) == NORMAL_LIST_VIEW){
        if (view == null){
            view = newView(mContext, getCursor(), parent);
        }
        getCursor().moveToPosition(cursorPositions.get(position));
        bindView(view, mContext, getCursor(), position);
    } else if (getItemViewType(position) == SECTION_LIST_VIEW) {
        if (view == null){
            view = newSectionView(mContext, getCursor(), parent);
        }
        bindSectionView(view, mContext, (char)sections.get(position));
    } else {
        if (view == null){
        } else {
            view = new ViewStub(mContext);
        }
    }
    return view;
}

public abstract View newSectionView(Context context, Cursor cursor, ViewGroup parent);

public abstract void bindSectionView(View view, Context context, char text);

public abstract void bindView(View view, Context context, Cursor cursor, int position);

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEnabled(int position) {
    return cursorPositions.get(position) >= 0;
}

@Override
public int getItemViewType(int position) {
    if (cursorPositions.get(position) >= 0){
        return NORMAL_LIST_VIEW;
    }else if (cursorPositions.get(position) == -1){
        return SECTION_LIST_VIEW;
    } else {
        return NULL_LIST_VIEW;
    }
}

@Override
public int getViewTypeCount() {
    return 3;
}

private void putCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition) {
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(position));
        cursorPositions.put(actualPosition, -position);
    }
}

private void removeCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition){
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(-position));
        cursorPositions.put(actualPosition, position);
    }
}

@Override
public int getCount() {
    return cursorPositions == null ? 0 : cursorPositions.size();
}

public SparseIntArray getSections() {
    return sections;
}

public SparseIntArray getCursorPositions() {
    return cursorPositions;
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    //do nothing here
}

@Override
public Cursor swapCursor(Cursor newCursor) {
    return super.swapCursor(newCursor);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void changeCursor(Cursor cursor) {
    setSortedCursorColumn(cursor);
    super.changeCursor(cursor);
}
}

getSections（）检索提供给字母索引器的字母表的字符串[]
AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, alphabets);

String[] sections = (String[]) alphabetIndexer.getSections();

public abstract class SectionedListAdapter extends ResourceCursorAdapter {

private SparseIntArray sections;
private SparseIntArray cursorPositions;
private Context mContext;
private int sortedColumnIndex;

private static final int NORMAL_LIST_VIEW = 0;
private static final int SECTION_LIST_VIEW = 1;
private static final int NULL_LIST_VIEW = 2;

public SectionedListAdapter(Context context, int layout, Cursor c,
                            boolean autoRequery, int sortedColumnIndex, int defaultBitmapResId) {
    super(context, layout, c, autoRequery);
    this.mContext = context;
    this.sortedColumnIndex = sortedColumnIndex;
    setSortedCursorColumn(c);
}

public void setSortedCursorColumn(Cursor cursor){
    if (cursor == null){
        return;
    }
    AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    sections = new SparseIntArray();
    int m=0;
    int t = 'A';
    for (int i=0; i < 26; i++){
        if ((i+1) < 26) {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i + 1);
            if (temp != position){
                sections.put(position + m, t+i);
                m++;
            }
        } else {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i-1);
            if (position != temp){
                sections.put(position + m, t+i);
            }
        }
    }
    int temp = 0;
    cursorPositions = new SparseIntArray();
    for (int i=0; i<cursor.getCount() + sections.size(); i++){
        if (sections.get(i, -1) != -1){
            temp ++;
            cursorPositions.put(i, -1);
        } else {
            cursorPositions.put(i, i - temp);
        }
    }
}

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (getItemViewType(position) == NORMAL_LIST_VIEW){
        if (view == null){
            view = newView(mContext, getCursor(), parent);
        }
        getCursor().moveToPosition(cursorPositions.get(position));
        bindView(view, mContext, getCursor(), position);
    } else if (getItemViewType(position) == SECTION_LIST_VIEW) {
        if (view == null){
            view = newSectionView(mContext, getCursor(), parent);
        }
        bindSectionView(view, mContext, (char)sections.get(position));
    } else {
        if (view == null){
        } else {
            view = new ViewStub(mContext);
        }
    }
    return view;
}

public abstract View newSectionView(Context context, Cursor cursor, ViewGroup parent);

public abstract void bindSectionView(View view, Context context, char text);

public abstract void bindView(View view, Context context, Cursor cursor, int position);

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEnabled(int position) {
    return cursorPositions.get(position) >= 0;
}

@Override
public int getItemViewType(int position) {
    if (cursorPositions.get(position) >= 0){
        return NORMAL_LIST_VIEW;
    }else if (cursorPositions.get(position) == -1){
        return SECTION_LIST_VIEW;
    } else {
        return NULL_LIST_VIEW;
    }
}

@Override
public int getViewTypeCount() {
    return 3;
}

private void putCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition) {
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(position));
        cursorPositions.put(actualPosition, -position);
    }
}

private void removeCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition){
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(-position));
        cursorPositions.put(actualPosition, position);
    }
}

@Override
public int getCount() {
    return cursorPositions == null ? 0 : cursorPositions.size();
}

public SparseIntArray getSections() {
    return sections;
}

public SparseIntArray getCursorPositions() {
    return cursorPositions;
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    //do nothing here
}

@Override
public Cursor swapCursor(Cursor newCursor) {
    return super.swapCursor(newCursor);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void changeCursor(Cursor cursor) {
    setSortedCursorColumn(cursor);
    super.changeCursor(cursor);
}
}

getSectionForPosition（position）检索当前位置的节
考虑给定的情况
position  Data             getSectionForPosition(position)
________  _________            __________

   0      Ajdhfj j             0
   1      Aadf hdsf            0
   2      Ajfkldsahf           0
   3      Asdhfa df            0
   4      Badhf                1
   5      Bdfj sadif           1
   6      Bghoi ij             1
   7      Bjkojg o             1
   8      Cadj fkljsdf         2
   9      Cgjds kfja           2
   10     Cn khdfaj            2
   11     Cph iohsdf           2
   12     Czjfa sh             2
   13     Dfgoa hjoifaj        3
   14     Dzfjdak sfh          3
   15     Fhf adhf             5
   16     Zdfh ajdf            25

获取该职位的部门
String section = sections[getSectionForPosition(position)];

getPositionForSection（section）检索数据从该节开始的第一个位置
section      getPositionForSection(section)
_________    ____________________
0            0
1            4
2            8
3            13
4            13
5            15
6            15
7            15
8            15
.            .
.            .
.            .
23           15
24           15          
25           16

希望这对你有帮助
使用字母索引器的示例
AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, alphabets);

String[] sections = (String[]) alphabetIndexer.getSections();

public abstract class SectionedListAdapter extends ResourceCursorAdapter {

private SparseIntArray sections;
private SparseIntArray cursorPositions;
private Context mContext;
private int sortedColumnIndex;

private static final int NORMAL_LIST_VIEW = 0;
private static final int SECTION_LIST_VIEW = 1;
private static final int NULL_LIST_VIEW = 2;

public SectionedListAdapter(Context context, int layout, Cursor c,
                            boolean autoRequery, int sortedColumnIndex, int defaultBitmapResId) {
    super(context, layout, c, autoRequery);
    this.mContext = context;
    this.sortedColumnIndex = sortedColumnIndex;
    setSortedCursorColumn(c);
}

public void setSortedCursorColumn(Cursor cursor){
    if (cursor == null){
        return;
    }
    AlphabetIndexer alphabetIndexer = new AlphabetIndexer(cursor, sortedColumnIndex, "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
    sections = new SparseIntArray();
    int m=0;
    int t = 'A';
    for (int i=0; i < 26; i++){
        if ((i+1) < 26) {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i + 1);
            if (temp != position){
                sections.put(position + m, t+i);
                m++;
            }
        } else {
            int position = alphabetIndexer.getPositionForSection(i);
            int temp = alphabetIndexer.getPositionForSection(i-1);
            if (position != temp){
                sections.put(position + m, t+i);
            }
        }
    }
    int temp = 0;
    cursorPositions = new SparseIntArray();
    for (int i=0; i<cursor.getCount() + sections.size(); i++){
        if (sections.get(i, -1) != -1){
            temp ++;
            cursorPositions.put(i, -1);
        } else {
            cursorPositions.put(i, i - temp);
        }
    }
}

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (getItemViewType(position) == NORMAL_LIST_VIEW){
        if (view == null){
            view = newView(mContext, getCursor(), parent);
        }
        getCursor().moveToPosition(cursorPositions.get(position));
        bindView(view, mContext, getCursor(), position);
    } else if (getItemViewType(position) == SECTION_LIST_VIEW) {
        if (view == null){
            view = newSectionView(mContext, getCursor(), parent);
        }
        bindSectionView(view, mContext, (char)sections.get(position));
    } else {
        if (view == null){
        } else {
            view = new ViewStub(mContext);
        }
    }
    return view;
}

public abstract View newSectionView(Context context, Cursor cursor, ViewGroup parent);

public abstract void bindSectionView(View view, Context context, char text);

public abstract void bindView(View view, Context context, Cursor cursor, int position);

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEnabled(int position) {
    return cursorPositions.get(position) >= 0;
}

@Override
public int getItemViewType(int position) {
    if (cursorPositions.get(position) >= 0){
        return NORMAL_LIST_VIEW;
    }else if (cursorPositions.get(position) == -1){
        return SECTION_LIST_VIEW;
    } else {
        return NULL_LIST_VIEW;
    }
}

@Override
public int getViewTypeCount() {
    return 3;
}

private void putCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition) {
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(position));
        cursorPositions.put(actualPosition, -position);
    }
}

private void removeCursorExclusion(int position, boolean isActualPosition){
    if (isActualPosition){
        cursorPositions.put(position, -cursorPositions.get(position));
    } else {
        int actualPosition = cursorPositions.keyAt(cursorPositions.indexOfValue(-position));
        cursorPositions.put(actualPosition, position);
    }
}

@Override
public int getCount() {
    return cursorPositions == null ? 0 : cursorPositions.size();
}

public SparseIntArray getSections() {
    return sections;
}

public SparseIntArray getCursorPositions() {
    return cursorPositions;
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    //do nothing here
}

@Override
public Cursor swapCursor(Cursor newCursor) {
    return super.swapCursor(newCursor);
}

@Override
public void notifyDataSetChanged() {
    super.notifyDataSetChanged();
}

@Override
public void changeCursor(Cursor cursor) {
    setSortedCursorColumn(cursor);
    super.changeCursor(cursor);
}
}

公共抽象类SectionListAdapter扩展了ResourceCursorAdapter{
私人SparseIntArray路段；
私人SparseIntArray光标位置；
私有上下文；
私有int-sortedColumnIndex；
私有静态最终int正常列表视图=0；
私有静态最终整型部分列表视图=1；
私有静态final int NULL_LIST_VIEW=2；
公共分区ListAdapter（上下文上下文、int布局、游标c、，
布尔自动请求，int-sortedColumnIndex，int-defaultBitmapResId）{
超级（上下文、布局、c、自动请求）；
this.mContext=上下文；
this.sortedColumnIndex=sortedColumnIndex；
setSortedCursorColumn（c）；
}
public void setSortedCursorColumn（光标）{
if（游标==null）{
返回；
}
字母索引器字母索引器=新的字母索引器（光标，分类列索引，“ABCDEFGHIJKLMNOPQRSTUVWXYZ”）；
截面=新SparseIntArray（）；
int m=0；
int t='A'；
对于（int i=0；i<26；i++）{
如果（（i+1）<26）{
int position=字母索引器。getPositionForSection（i）；
int temp=字母索引器getPositionForSection（i+1）；
如果（温度！=位置）{
放置（位置+m，t+i）；