Drop-down Refresh (ii)

First look at the main layout activity_main.xml

<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 "    android:background= "@color/white"    tools:context= ". Mainactivity ">    <com.imooc.listviewfrashdemo1.reflashlistview        android:id=" @+id/listview "        Android:layout_width= "Fill_parent"        android:layout_height= "fill_parent"        android:background= "@color/ White "        android:cachecolorhint=" #00000000 "        android:dividerheight=" 5dip "/></relativelayout>

Re-header_layout.xml 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 " > <relativelayout android:layout_width= "match_parent" android:layout_height= "Wrap_content" a Ndroid:paddingbottom= "10dip" android:paddingtop= "10dip" > <linearlayout android:id= "@+id/la Yout "android:layout_width=" wrap_content "android:layout_height=" Wrap_content "Android:la Yout_centerinparent= "true" android:gravity= "center" android:orientation= "vertical" > & Lt TextView android:id= "@+id/tip" android:layout_width= "Wrap_content" Android:la yout_height= "Wrap_content" android:text= "drop-down can be refreshed!           "/> <textview android:id=" @+id/lastupdate_time "     Android:layout_width= "Wrap_content" android:layout_height= "wrap_content"/> </linearlayou t> <imageview android:id= "@+id/arrow" android:layout_width= "Wrap_content" an droid:layout_height= "Wrap_content" android:layout_toleftof= "@id/layout" android:layout_marginright= " 20dip "android:src=" @drawable/pull_to_refresh_arrow "/> <progressbar android:id=" @+id/p            Rogress "style="? Android:attr/progressbarstylesmall "Android:layout_width=" Wrap_content " android:layout_height= "Wrap_content" android:layout_toleftof= "@id/layout" android:layout_marginright = "20dip" android:visibility= "Gone"/> </RelativeLayout></LinearLayout>

Look at the layout of each item in the ListView

Item_layout.xml

<?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=" match_parent "android:orientation=" vertical " > <linearlayout android:layout_width= "fill_parent" android:layout_height= "60dip" Android:gra        Vity= "center_vertical" android:background= "@drawable/app_item_bg" android:orientation= "Horizontal" > <imageview android:id= "@+id/item3_apkiv" android:layout_width= "50dip" android:layou        t_height= "50dip" android:background= "@drawable/test_icon" android:layout_marginleft= "10dip"/>            <linearlayout android:layout_width= "wrap_content" android:layout_height= "Wrap_content" android:layout_weight= "1" android:layout_marginleft= "10dip" android:orientation= "vertical"            ;          <textview      Android:id= "@+id/item3_apkname" android:layout_width= "Wrap_content" Android:layout_hei ght= "Wrap_content" android:text= "Application Name" android:textcolor= "@color/black" and Roid:textsize= "18dip"/> <textview android:id= "@+id/item3_apkinfo" Android: Layout_width= "Wrap_content" android:layout_height= "Wrap_content" android:layout_margintop= "5        Dip "android:text=" Application Information "android:textsize=" 14dip "/> </LinearLayout> <button android:layout_width= "60dip" android:layout_height= "30dip" Android:backgroun            d= "@drawable/ic_launcher" android:id= "@+id/item3_dlbtn" android:layout_marginright= "10dip"        android:text= "Install"/> </LinearLayout> <textview android:id= "@+id/item3_apkdes" Android:layout_width= "FIll_parent "android:layout_height=" 30dip "android:layout_marginleft=" 5dip "android:layout_marginright = "5dip" android:gravity= "center_vertical" android:text= "Application description" android:textsize= "14dip"/></li Nearlayout>

The above three layouts can be seen, know a ballpark, this is not the main

Next look at the Bean class

Apkentity

Package Com.imooc.listviewfrashdemo1;public class Apkentity {private string Name;private string Des;private string info; Public String GetName () {return name;} public void SetName (String name) {this.name = name;} Public String Getdes () {return des;} public void Setdes (String des) {this.des = des;} Public String GetInfo () {return info;} public void SetInfo (String info) {this.info = info;}}

Next look at the main process code

Mainactivity

Package Com.imooc.listviewfrashdemo1;import Java.util.arraylist;import Android.app.activity;import Android.os.bundle;import Android.os.handler;import Com.example.listviewfrashdemo1.r;import Com.imooc.listviewfrashdemo1.reflashlistview.ireflashlistener;public class Mainactivity extends Activity implements Ireflashlistener {arraylist<apkentity> apk_list; Myadapter adapter; Reflashlistview listview, @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate ( savedinstancestate);//Load layout--only one listviewsetcontentview (r.layout.activity_main);//Set Data SetData ();//Fill Data showlist ( apk_list);} /** * Set data source */private void SetData () {apk_list = new arraylist<apkentity> (); for (int i = 0; i < i++) {Apkenti Ty entity = new apkentity (), Entity.setname ("Default data"), Entity.setinfo ("50w user") Entity.setdes ("This is a magical application"); Apk_list.add (entity);}} private void Showlist (arraylist<apkentity> apk_list) {if (adapter = = NULL) {ListView = (Reflashlistview) Findviewby Id (R.id.listview);//Set the listener for this class, and thenImplements Ireflashlistenerlistview.setinterface (This): adapter = new Myadapter (this, apk_list);//If the adapter is null, Set the adapter to Listview.setadapter (adapter);} else {//If the adapter is not NULL, update the data source for notifydatasetchanged () Adapter.ondatechange (apk_list);}} /** * Callback method to implement refresh operation */@Overridepublic void Onreflush () {Handler Handler = new Handler (); handler.postdelayed (new Runnable () {@Overridepublic void Run () {//Gets the latest data setreflashdata ();//Notification interface displays showlist (apk_list);//Notify ListView to Refresh Data!!!!!!!!!!!!!! Listview.reflashcomplete ();}}, 2000);} private void Setreflashdata () {for (int i = 0; i < 2; i++) {apkentity entity = new apkentity (); Entity.setname ("Refresh Data"); E Ntity.setdes ("This is a magical application"); Entity.setinfo ("50w user"); Apk_list.add (0, entity);}}

Next look at the adapter code

Myadapter

Package Com.imooc.listviewfrashdemo1;import Java.util.arraylist;import Com.example.listviewfrashdemo1.r;import Android.content.context;import Android.view.layoutinflater;import Android.view.view;import Android.view.ViewGroup ; Import Android.widget.baseadapter;import Android.widget.textview;public class Myadapter extends Baseadapter { Arraylist<apkentity> apk_list; Layoutinflater Inflater;public Myadapter (context context, arraylist<apkentity> apk_list) {this.apk_list = Apk_ List;this.inflater = Layoutinflater.from (context);} public void Ondatechange (arraylist<apkentity> apk_list) {this.apk_list = Apk_list;this.notifydatasetchanged ();} @Overridepublic int GetCount () {return apk_list.size ();} @Overridepublic Object getItem (int position) {return apk_list.get (position);} @Overridepublic long Getitemid (int position) {return position;} @Overridepublic view GetView (int position, view Convertview, ViewGroup parent) {apkentity entity = apk_list.get (position) ; Viewholder Holder;if (converTView = = null) {holder = new Viewholder (); Convertview = Inflater.inflate (r.layout.item_layout, null); HOLDER.NAME_TV = (Te Xtview) Convertview.findviewbyid (r.id.item3_apkname); holder.des_tv = (TextView) Convertview.findviewbyid ( R.id.item3_apkdes); Holder.info_tv = (TextView) Convertview.findviewbyid (r.id.item3_apkinfo); Convertview.settag ( Holder);} Else{holder = (Viewholder) Convertview.gettag ();} Holder.name_tv.setText (Entity.getname ()); Holder.des_tv.setText (Entity.getdes ()); Holder.info_tv.setText ( Entity.getinfo ()); return Convertview;} Class Viewholder {TextView name_tv; TextView Des_tv; TextView Info_tv;}}

Next look at the custom ListView class (inside the code details)

Reflashlistview

Package Com.imooc.listviewfrashdemo1;import Java.text.simpledateformat;import Java.util.date;import Android.content.context;import Android.util.attributeset;import Android.util.log;import Android.view.layoutinflater;import Android.view.motionevent;import Android.view.view;import Android.view.viewgroup;import Android.view.animation.rotateanimation;import Android.widget.abslistview;import Android.widget.abslistview.onscrolllistener;import Android.widget.imageview;import Android.widget.ListView; Import Android.widget.progressbar;import android.widget.textview;import com.example.listviewfrashdemo1.r;/** * Hide header Layout--first measure parent layout, layout height, set padding, then hide header layout, listview in Add header layout * Set Listener event * Determine ontouch time * Set listener load refreshed data */public class Reflashlistview extends ListView implements Onscrolllistener {View header;//top layout file; int headerheight;//height of top layout file; int firstvisibleitem;//the position of the currently first visible item, int scrollstate;//listview Current scrolling state; Boolean isremark;//tag, currently at the top of the listview; int starty;//the Y value when pressed, int state;//the current state; final int NONE = 0;//normal state; final int pull = 1;//hint drop-down state; final int relese = 2;//prompt release status; final int reflashing = 3;//refresh State; Ireflashlistener ireflushlistener;//refreshes the data interface/** * Three constructor methods, and initializes the view */public Reflashlistview (context context) {super (context); Initview ( context);} Public Reflashlistview (context context, AttributeSet Attrs) {Super (context, attrs); Initview (context);} Public Reflashlistview (context context, AttributeSet attrs, int defstyle) {Super (context, attrs, Defstyle); Initview ( context);} /** * Initialize interface, add top layout file to ListView */private void Initview (context context) {Layoutinflater inflater = Layoutinflater.from (co ntext); header = Inflater.inflate (r.layout.header_layout, NULL);//First measure parent layout, otherwise headerheight is 0measureView (header);// Gets the height of the header layout file Headerheight = Header.getmeasuredheight (); LOG.I ("tag", "headerheight =" + headerheight);//Hide Header Layout file toppadding (-headerheight);//listview Add header Layout This.addheaderview (header);//Set Slide monitor this.setonscrolllistener (this);} /** * Notifies the parent layout, occupies a wide, high, */private void Measureview (view view) {Viewgroup.layoutparAMS P = view.getlayoutparams (); if (p = = null) {p = new Viewgroup.layoutparams (ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);} /** * Because the ListView does not limit height. How high the child is, the ListView gives it much space * But the ListView is limited in width, so it needs getchildmeasurespec */int width = viewgroup.getchildmeasurespec (0, 0 , p.width); int height;//Gets the height value of itme int tempheight = p.height;if (Tempheight > 0) {height = Measurespec.makemeasurespec ( tempheight,measurespec.exactly);} else {height = measurespec.makemeasurespec (0, measurespec.unspecified);} View.measure (width, height);} /** * Sets the top margin of the header layout;--look at the problem from the perspective of the parent layout */private void toppadding (int toppadding) {header.setpadding (header.getpaddingleft (), Toppadding,header.getpaddingright (), Header.getpaddingbottom ()); Header.invalidate ();} /** * Implement Interface method */@Overridepublic void onscroll (abslistview view, int firstvisibleitem,int visibleitemcount, int Totalitemco UNT) {this.firstvisibleitem = Firstvisibleitem;} @Overridepublic void onscrollstatechanged (abslistview view, int scrollstate) {this.scrollstate = scrollstate;} /** * Implement Touch Method */@Overridepublic Boolean ontouchevent (motionevent ev) {switch (ev.getaction ()) {/** * If the finger is pressed, if Firstvisi Bleitem = = 0 Sets the mark to True, which represents the top pressed * and gets the coordinates of the y-axis distance */case MotionEvent.ACTION_DOWN:if (Firstvisibleitem = = 0) {Isremark = tr Ue;starty = (int) ev.gety ();} Break;case motionevent.action_move:/** * Judge the movement process operation; */onmove (EV); break;case MotionEvent.ACTION_UP:if (state = = Relese) { state = reflashing;//Load up-to-date data; Reflashviewbystate (); Ireflushlistener.onreflush ();} else if (state = = pull) {state = None;isremark = False;reflashviewbystate ();} break;} return super.ontouchevent (EV);} /** * When the finger is pressed */private void OnMove (motionevent ev) {//If it is not pressed at the top of the ListView, return directly, do not process if (!isremark) {return;} int tempy = (int) ev.gety ();//Gets the moving distance int space = tempy-starty;//Gets the padding value of the latest header layout int toppadding = Space-headerheight;s Witch (state) {/** * Determines the status value of the refresh arrow */case none://If you move it a little bit to the state--drop-down can refresh if (Space > 0) {///if it is normal, modify the state to a drop-down to refresh states = pull;// Change the interface display according to the current state; REFLASHVIEWBYstate ();} Break;case pull://Redraw The latest head layout hiding degree toppadding (toppadding);//If you change the state value directly if it is greater than 30 of the head layout height if (space-headerheight> 30& & scrollstate = = Scroll_state_touch_scroll) {//Modify status is--release can refresh state = Relese;reflashviewbystate ();} Break;case relese://Redraw The latest header layout hiding degree toppadding (toppadding); if (Space-headerheight < 30) {//Change state--the drop-down can be refreshed by the status = pull; Reflashviewbystate ();} else if (space <= 0) {//when space<=0, the visible item index is not 0state = none;//restore Isremark = False;reflashviewbystate ();} Break;}} /** * Changes the interface display according to the current state, */private void Reflashviewbystate () {TextView tip = (TextView) Header.findviewbyid (r.id.tip); I Mageview arrow = (ImageView) Header.findviewbyid (R.id.arrow); ProgressBar progress = (ProgressBar) Header.findviewbyid (r.id.progress); Rotateanimation anim = new Rotateanimation (0, 180,rotateanimation.relative_to_self, 0.5f,rotateanimation.relative_to _self, 0.5f); anim.setduration (+); Anim.setfillafter (true); Rotateanimation anim1 = new Rotateanimation (0,rotateanimation.relative_to_self, 0.5f,rotateanimation. Relative_to_self, 0.5f); anim1.setduration (+); Anim1.setfillafter (true); switch (state) {case NONE: Arrow.clearanimation (); toppadding (-headerheight); Break;case PULL:arrow.setVisibility (view.visible); Progress.setvisibility (View.gone); Tip.settext ("Pull down to refresh! "); Arrow.clearanimation (); arrow.setanimation (ANIM1); Break;case RELESE:arrow.setVisibility (view.visible); Progress.setvisibility (View.gone); Tip.settext ("Release can be refreshed! "); Arrow.clearanimation (); arrow.setanimation (anim); break;case reflashing:toppadding (); Arrow.setvisibility ( View.gone);p rogress.setvisibility (view.visible); Tip.settext ("refreshing ..."); Arrow.clearanimation (); break;}} /** * get finished data; */public void Reflashcomplete () {//Restores the refresh state to a normal state = none;//Restore state Isremark = False;reflashviewbystate (); TextView lastupdatetime = (TextView) Header.findviewbyid (r.id.lastupdate_time); SimpleDateFormat format = new SimpleDateFormat ("yyyy mm month DD Day HH:MM:SS");D ate date = new Date (System.currenttimemillis ()) ; String time = Format.format (date); Lastupdatetime.settext (TiMe);} public void Setinterface (Ireflashlistener ireflushlistener) {this.ireflushlistener = Ireflushlistener;} /** * Refresh Data interface * @author Administrator */public interface ireflashlistener{public void Onreflush ();}}

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Drop-down Refresh (ii)