public class Content {

Private String letter; 
private String name; 



Public Content (String letter, String name) {
Enclosing letter=letter; 
This. Name=name; 
} 
Public String getLetter () {
The return letter; 
} 
Public void setLetter (String letter) {
Enclosing letter=letter; 
} 
Public String getName () {
Return the name; 
} 
Public void elegantly-named setName (String name) {
This. Name=name; 
} 


} 

 public class MainActivity extends the Activity 
{

Private ListView mListView; 

Public void onCreate (Bundle savedInstanceState) 
{
Super. OnCreate (savedInstanceState); 
The setContentView (R.l ayout. Activity_main); 
MListView=(ListView) the findViewById (R.i d.l istInfo); 


//initialization data 
List List=new ArrayList (a); 
For (int I=0; I & lt; 10; I++) {
The Content of m. 
If (I & lt; 3) 
M=new Content (" A ", "b"); 
Else if (I & lt; 6) 
M=new Content (" F ", "party"); 
The else 
M=new Content (" D ", "east"); 
List. Add (m); 
} 

//instantiate custom content adaptation class 
MyAdapter adapter=new MyAdapter (this, a list); 
//for listView 
MListView. SetAdapter (adapter); 

} 

} 

 public class MyAdapter extends BaseAdapter {

Private List List=null; 
Private Context mContext; 

Public MyAdapter (Context mContext List The list) {
Enclosing mContext=mContext; 
Enclosing a list=list; 

} 

Public int getCount () {
Return this. The list. The size (); 
} 

Public Object the getItem (int position) {
return null; 
} 

Public long getItemId (int position) {
Return the position; 
} 

Public View getView (final int position, View View and ViewGroup arg2) {
ViewHolder ViewHolder=null; 
If (view==null) {
ViewHolder=new viewHolder (); 
View=LayoutInflater. The from (mContext). Inflate (R.l ayout. Item, null); 
ViewHolder. TvTitle=(TextView) view. The findViewById (R.i which itle); 
ViewHolder. TvLetter=(TextView) view. The findViewById (R.i, dc atalog); 
The setTag (viewHolder); 
} else {
ViewHolder=(viewHolder) the getTag (); 
} 
The final Content mContent=list. Get (position); 
If (position==0) {
ViewHolder. TvLetter. SetVisibility (the VISIBLE). 
ViewHolder. TvLetter. SetText (mContent getLetter ()); 
} else {
String lastCatalog=list. Get (position 1) getLetter (); 
If (mContent. GetLetter (.) the equals (lastCatalog)) {
ViewHolder. TvLetter. SetVisibility (View. GONE); 
} else {
ViewHolder. TvLetter. SetVisibility (the VISIBLE). 
ViewHolder. TvLetter. SetText (mContent getLetter ()); 
} 
} 

ViewHolder. TvTitle. SetText (enclosing a list. The get (position). The getName ()); 

Return the view; 

} 



Final static class ViewHolder {
TextView tvTitle; 
TextView tvLetter; 
} 


Public Object [] getSections () {
//TODO Auto - generated method stub 
return null; 
} 

Public int getSectionForPosition (int position) {

return 0; 
} 

Public int getPositionForSection (int section) {
The Content mContent; 
String l; 
If (section=='! ') {
return 0; 
} else {
For (int I=0; I & lt; GetCount (); I++) {
MContent=(Content) list. Get (I); 
L=mContent. GetLetter (); 
Char firstChar=l.t oUpperCase (). The charAt (0); 
If (firstChar==section) {
Return the I + 1; 
} 

} 
} 
MContent=null; 
L=null; 
return -1; 
} 
} 

CodePudding user response:

 & lt; RelativeLayout XMLNS: android="http://schemas.android.com/apk/res/android" 
XMLNS: tools="http://schemas.android.com/tools" 
Android: layout_width="match_parent" 
Android: layout_height="match_parent" 
Tools: context="com. Example. Action. MainActivity" & gt; 

The android: id="@ + id/list_title" 
Android: layout_width="fill_parent" 
Android: layout_height="wrap_content" 
Android: textSize="18 dp" 
Android: padding="5 dp" 
Android: background="# e1e1e1" 
Android: textColor="# f00" 
Android: text="B" 
Android: layout_alignParentTop="true" 
Android: visibility="visible"/& gt; 

Android: layout_below="@ id/list_title" 
Android: focusable="true" 
Android: layout_height="wrap_content" 
Android: layout_width="fill_parent" 
Android: scrollbars="none" 
Android: cacheColorHint="# 00000000" 
Android: background="# FFF"/& gt; 

 

 & lt; ? The XML version="1.0" encoding="utf-8"?> 
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