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//按字母a~z排序
Collections.sort(mList, new Comparator<FriendInfo>() {
@Override
public int compare(FriendInfo o1, FriendInfo o2) {
char str1 = PinYinUtils.getPinYinFirstChar(o1.getName());
char str2 = PinYinUtils.getPinYinFirstChar(o2.getName());
if (str1 < str2){
return -1;
}else {
return 1;
}
}
});
adapter.notifyDataSetChanged(mList);
//适配器adapter
public class FriendAdapter extends RecyclerView.Adapter<FriendAdapter.ViewHolder> {
private Context mContext;
private List<FriendInfo> mList = new ArrayList<>();
private LayoutInflater inflater;
public FriendAdapter(Context context, List<FriendInfo> list){
this.mContext = context;
this.mList = list;
initPinYin(mList);
this.inflater = LayoutInflater.from(mContext);
}
@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
View view = inflater.inflate(R.layout.friend_item, viewGroup, false);
ViewHolder holder = new ViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(@NonNull ViewHolder viewHolder, int i) {
String currentStr = PinYinUtils.getPinYinFirstLetter(mList.get(i).getName());
String previewStr = (i - 1)>= 0? PinYinUtils.getPinYinFirstLetter(mList.get(i - 1).getName()): "";
if (!currentStr.equals(previewStr)){
viewHolder.tv_pinyin.setVisibility(View.VISIBLE);
viewHolder.tv_pinyin.setText(currentStr.toUpperCase());
}else {
viewHolder.tv_pinyin.setVisibility(View.GONE);
}
Glide.with(mContext).load(mList.get(i).getFaddr()).into(viewHolder.iv_icon);
viewHolder.tv_name.setText(mList.get(i).getName());
}
@Override
public int getItemCount() {
return mList.size();
}
public static class ViewHolder extends RecyclerView.ViewHolder{
private TextView tv_pinyin;
private ImageView iv_icon;
private TextView tv_name;
public ViewHolder(@NonNull View itemView) {
super(itemView);
tv_pinyin = itemView.findViewById(R.id.tv_pinyin);
iv_icon = itemView.findViewById(R.id.iv_icon);
tv_name = itemView.findViewById(R.id.tv_name);
}
}
public void notifyDataSetChanged(List<FriendInfo> list){
mList = list;
initPinYin(mList);
notifyDataSetChanged();
}
private HashMap<String, Integer> pyMap = new HashMap<>();
/***
* 获取好友对应首字母下标排序
* @param list
*/
private void initPinYin(List<FriendInfo> list){
for (int i = 0; i < list.size(); i++) {
String currentStr = PinYinUtils.getPinYinFirstLetter(list.get(i).getName());
String previewStr = (i - 1)>= 0? PinYinUtils.getPinYinFirstLetter(list.get(i - 1).getName()): "";
if (!currentStr.equals(previewStr)){
pyMap.put(currentStr, i);
}
}
}
}
//xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="@+id/tv_pinyin"
android:layout_width="match_parent"
android:layout_height="45dp"
android:background="@color/pinyin1"
android:paddingLeft="20dp"
android:textSize="18sp"
android:gravity="center_vertical"
android:text="A"/>
<TextView
android:id="@+id/tv_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:gravity="center"
android:text="阿牛"
android:textColor="@color/text_color"
android:textSize="15sp" />
</LinearLayout>
/**
* 获取汉字字符串的第一个字母
*/
public static String getPinYinFirstLetter(String str) {
sb.setLength(0);
char c = str.charAt(0);
String[] pinyinArray = PinyinHelper.toHanyuPinyinStringArray(c);
if (pinyinArray != null) {
sb.append(pinyinArray[0].charAt(0));
} else {
sb.append(c);
}
return sb.toString();
}
/**
* 获取汉字字符串的第一个字母
*/
public static char getPinYinFirstChar(String str) {
char c = str.charAt(0);
String[] pinyinArray = PinyinHelper.toHanyuPinyinStringArray(c);
if (pinyinArray != null) {
c = pinyinArray[0].charAt(0);
}
return c;
}
/***
* 右侧字母自定义view
*
*/
public class QuickLocationBar extends View {
private String characters[] = { "#", "A", "B", "C", "D", "E", "F", "G",
"H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T",
"U", "V", "W", "X", "Y", "Z" };
private int choose = -1;
private Paint paint = new Paint();
private OnTouchLetterChangedListener mOnTouchLetterChangedListener;
private TextView mTextDialog;
public QuickLocationBar(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
public QuickLocationBar(Context context, AttributeSet attrs) {
super(context, attrs);
}
public QuickLocationBar(Context context) {
super(context);
}
public void setOnTouchLitterChangedListener(
OnTouchLetterChangedListener onTouchLetterChangedListener) {
this.mOnTouchLetterChangedListener = onTouchLetterChangedListener;
}
public void setTextDialog(TextView dialog) {
this.mTextDialog = dialog;
}
@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
int width = getWidth();
int height = getHeight();
int singleHeight = height / characters.length;
for (int i = 0; i < characters.length; i++) {
// 对paint进行相关的参数设置
paint.setColor(getResources().getColor(R.color.huise));
paint.setTypeface(Typeface.DEFAULT_BOLD);
paint.setAntiAlias(true);
paint.setTextSize(150*(float) width/320);
if (i == choose) {// choose变量表示当前显示的字符位置，若没有触摸则为-1
paint.setColor(getResources().getColor(R.color.huise));
paint.setFakeBoldText(true);
}
// 计算字符的绘制的位置
float xPos = width / 2 - paint.measureText(characters[i]) / 2;
float yPos = singleHeight * i + singleHeight;
// 在画布上绘制字符
canvas.drawText(characters[i], xPos, yPos, paint);
paint.reset();// 每次绘制完成后不要忘记重制Paint
}
}
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
int action = event.getAction();
float y = event.getY();
int c = (int) (y / getHeight() * characters.length);
switch (action) {
case MotionEvent.ACTION_UP:
choose = -1;//
setBackgroundColor(0x0000);
invalidate();
if (mTextDialog != null) {
mTextDialog.setVisibility(View.GONE);
}
break;
case MotionEvent.ACTION_DOWN:
case MotionEvent.ACTION_MOVE:
//setBackgroundColor(getResources().getColor(R.color.bg_653fac));
if (choose != c) {
if (c >= 0 && c < characters.length) {
if (mOnTouchLetterChangedListener != null) {
mOnTouchLetterChangedListener
.touchLetterChanged(characters[c]);
}
if (mTextDialog != null) {
mTextDialog.setText(characters[c]);
mTextDialog.setVisibility(View.VISIBLE);
}
choose = c;
invalidate();
}
}
break;
}
return true;
}
public interface OnTouchLetterChangedListener {
public void touchLetterChanged(String s);
}
}