How to get Android phone contacts and show them by Alphabet (i)

Android provides a query URI for the local database that can be queried for data:

The use of a asyncqueryhandler to query, Asyncqueryhandler himself opened a thread for data query, very convenient

Protected Asyncqueryhandler mqueryhandler;protected final void querypersonal () {Mqueryhandler.startquery (QUERY_TOKEN , NULL, ContactsContract.Contacts.CONTENT_URI, personal.contacts_summary_projection, NULL, NULL, Getsortorder ( ContactsContract.Contacts.DISPLAY_NAME));} protected static string Getsortorder (String fieldName) {//substr is the Intercept function, taking the first letter//collate is primarily used to rank characters//collate localized Sort by local language return "case when substr (UPPER (" + FieldName + "), 1, 1) between ' A ' and ' Z ' then 1 else ten END," +fieldname + " COLLATE localized ASC ";} Protected final class MyHandler extends Asyncqueryhandler {/** * Asynchronous Query handler constructor. */public Myhandl ER (context context) {super (Context.getcontentresolver ());} /** * on query completion. */@Override <strong>protected void onquerycomplete (int token, Object cookie, cursor cursor) </strong>{// Handler query completed callback if (cursor = = NULL | | cursor.isclosed ()) {return;} if (!isfinishing ()) {setloading (false); if (madapter! = null) {madapter.setloading (FALSE); madapter.changecursor (cursor);} if (cursor.getcount () = = 0) {memtytext.setvisibility (view.visible);} else {memtytext.setvisibility (view.invisible);}} else {if (cursor! = NULL &&!cursor.isclosed ()) {cursor.close ();}}}}

This layout is:

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "xmlns:rcm=" Http://schemas.android.com/apk/res/com.ringcentral.android "android:id=" @+id/contact_list_ View "android:layout_width=" Match_parent "android:layout_height=" match_parent "android:background=" @color/bgcolor Main "android:orientation=" vertical "> <listview android:id=" @android: Id/list "Android:layout_wid        Th= "Match_parent" android:layout_height= "match_parent" android:cachecolorhint= "@android: Color/transparent" Android:descendantfocusability= "afterdescendants" android:divider= "@null" android:fastscrollenabled= "t Rue "android:listselector=" @drawable/bg_list_item_selector "/> <relativelayout android:id=" @+id/no_ Contact_indication "android:layout_width=" match_parent "android:layout_height=" Match_parent "> < TextView android:id= "@+id/emptYlisttext "android:layout_width=" wrap_content "android:layout_height=" Wrap_content "Andro Id:layout_centerinparent= "true" android:singleline= "true" android:text= "No Contacts" Android Oid:textcolor= "@color/text_no_items" android:textsize= "20sp"/> <progressbar android:id = "@+id/loading" style= "@style/rcmprogressbar" android:layout_width= "Wrap_content" Android    : layout_height= "Wrap_content" android:layout_centerinparent= "true" android:visibility= "Gone"/> </RelativeLayout></LinearLayout>

Then the list adapter is written:

Protected static Final class Sectionedcontactlistitemcache {public TextView sectionheader;public TextView Nameview;        Public TextView typeview;public ImageView photoview;public ImageView Detailitemicon; <span style= "White-space:pre" ></span>public View Nametypewrapper;} Protected final class Contactsadapter extends Resourcecursoradapter {public Contactsadapter (context context) {Super ( context, r.layout.contacts_list_item_photo,null);} @Overridepublic void Changecursor (Cursor c) {super.changecursor (c);} Protected string GetTitle (String displayName) {string title;/** Check if the first letter is 中文版 letter */matcher MATC her = Mpattern.matcher (DisplayName), if (!matcher.find ()) {title = None_english_letter_title;} else {title = Displayname.trim (). substring (0, 1). toUpperCase (locale.us);} return title;} Protected string GetDisplayName (Cursor c) {String displayName = c.getstring (Personal.name_column_index); Textutils.isempty (DisplayName)) {return "";} return displayName;} @Overridepublic void BindView (view view, context context, cursor cursor) {final Sectionedcontactlistitemcache cache = (Sectione Dcontactlistitemcache) View.gettag (); cache.typeView.setVisibility (View.gone); Cache.photoView.setVisibility ( view.visible); String name = cursor.getstring (Personal.name_column_index), if (Textutils.isempty (name)) {Cache.nameView.setText ( R.string.contact_no_name);} else {cache.nameView.setText (name);}}  @Overridepublic View Newview (context context, cursor cursor, viewgroup parent) {View view = Super.newview (context, cursor,            parent); final Sectionedcontactlistitemcache cache = new Sectionedcontactlistitemcache (); Cache.nametypewrapper = View.findviewbyid (r.id.name_type); cache.sectionheader = (TextView) View.findviewbyid ( R.id.txtsectionheader); Cache.nameview = (TextView) View.findviewbyid (r.id.name); Cache.typeview = (TextView) View.findviewbyid (r.id.type); Cache.photoview = (ImageView) View.findviewbyid (r.id.photo); Cache.detailitemicon = ( ImageView) view.findviewbyiD (R.id.contacts_detail_item_icon); View.settag (cache); return view;}} End of Adapter

Item Adapter Layout:

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "Android:layout_width=" Match_parent "android:layout_height=" wrap_content "android:orientation=" vertical "&    Gt <textview android:id= "@+id/txtsectionheader" android:layout_width= "Match_parent" android:layout_he ight= "@dimen/list_item_section_height" android:background= "@drawable/bg_contacts_section_header" Android:gra Vity= "Center_vertical|left" android:paddingleft= "@dimen/default_padding_to_side" android:textcolor= "@color/C Ontacts_text_separator_text_color "android:textsize=" @dimen/font_size_medium "/> <relativelayout an Droid:id= "@+id/contact_item" android:layout_width= "match_parent" android:layout_height= "@dimen/general_list_ View_item_height "> <imageview android:id=" @+id/photo "android:layout_width=" @dimen/favo   Rites_item_picture_width "         android:layout_height= "Match_parent" android:layout_alignparentleft= "true" android:layout_a Lignwithparentifmissing= "true" android:paddingtop= "6DP" android:paddingbottom= "6DP" Andro        id:layout_marginleft= "@dimen/contact_photo_margin_left_right" android:scaletype= "Fitcenter"/> <!--This icon is added in next version, and now it would is hidden---<imageview and            Roid:id= "@+id/contacts_detail_item_icon" android:layout_width= "50dip" android:layout_height= "60dip" Android:layout_alignparentright= "true" android:layout_marginright= "0dip" Android:croptopa Dding= "true" android:duplicateparentstate= "false" android:paddingbottom= "3dip" Android:pa ddingtop= "3dip" android:scaletype= "Fitcenter" android:src= "@drawable/ic_list_link" Androi D:visibility= "Gone"/> <relativelayout android:id= "@+id/name_type" android:layout_width= "Match_parent" Androi d:layout_height= "Match_parent" android:layout_alignwithparentifmissing= "true" Android:layout_tolefto            f= "@id/contacts_detail_item_icon" android:layout_marginleft= "@dimen/contact_photo_margin_left_right" android:layout_torightof= "@id/photo" android:background= "@drawable/bg_list_item_divider" > <te Xtview android:id= "@+id/type" android:layout_width= "Wrap_content" Android:lay out_height= "Wrap_content" android:layout_alignbaseline= "@+id/name" Android:layout_alignparen Tright= "true" android:layout_marginright= "@dimen/contact_type_margin_left_right" Android:ell                Ipsize= "marquee" android:gravity= "Center_vertical|right" android:singleline= "true" Android:tExtcolor= "@color/refresh_control_text_color" android:textsize= "@dimen/font_size_small"/> &lt ; TextView android:id= "@+id/name" android:layout_width= "Match_parent" android:l ayout_height= "Wrap_content" android:layout_centervertical= "true" android:layout_marginright= "@dimen/contact_name_margin_left_right" android:layout_toleftof= "@id/type" android:ellipsize = "marquee" android:gravity= "Center_vertical|left" android:singleline= "true" a Ndroid:textcolor= "@color/text_color_main" android:textsize= "@dimen/font_size_medium"/> </rela Tivelayout> </RelativeLayout></LinearLayout>