How does Android implement the status of the wireless loop slide of the focus graph?

Reference URL: http://my.oschina.net/xsk/blog/119167

The original implementation principle: Here is a simulation way to achieve the "wireless loop", in fact, is not the real sense of the wireless loop. Instead, the set value is large and is used as a wireless loop.

Code:

Package Stu.hades;import Android.content.context;import Android.support.v4.view.viewpager;import Android.util.attributeset;import Android.widget.imageview;import Android.widget.linearlayout;import Android.widget.relativelayout;import Com.example.hadesviewpagerdemo.r;public class MyViewPager extends ViewPager { protected Context mcontext = null;    protected Viewpager Viewpager = null; 1, define the image resource array, there are several write several, you can also dynamically fill public static int[] Imageresid = new int[] {R.drawable.aaa,r.drawable.aab, R.DRAWABLE.AAC,    R.drawable.aad};        2. Initialize some parameters public Myviewpager (context context, AttributeSet Attrs) {Super (context, attrs);        This.mcontext = context; Viewpager = this;        }//3, configure the adapter after the view is initialized and listen @Override protected void Onfinishinflate () {super.onfinishinflate ();        Viewpager.setadapter (New Myadapter (Mcontext));        Set the revelation location so big so that you can loop 100,000 times left, and no one should slide so often!        Viewpager.setcurrentitem (100000 * imageresid.length); Viewpager.setonpagechangelistener (New MyPagechangelistener ()); }//3, Picture Change listener private class Mypagechangelistener implements Onpagechangelistener {protected int oldposit        ion = 0; Below is a circle showing the current picture position, here is a reference, you can write yourself, even if the comment does not affect the sliding public void onpageselected (int position) {//LinearLayout ima Ge_viewpager_circle = (linearlayout) ((relativelayout) viewpager.getparent ()). Findviewbyid (R.id.main_image_ viewpager_circle);//((ImageView) Image_viewpager_circle.getchildat (oldposition)). Setimageresource (R.DRAWABLE.D Ot_normal);//((ImageView) Image_viewpager_circle.getchildat (position% imageresid.length)). Setimageresource (R.D            rawable.dot_focused);        oldposition = position% Imageresid.length;  } public void onpagescrollstatechanged (int arg0) {} public void onpagescrolled (int arg0, float arg1, int arg2) {}} @Override protected void onmeasure (int arg0, int arg1) {super.onmeasure (arg0, arg    1); }}

2 Adapter

Package Stu.hades;import Android.content.context;import Android.os.parcelable;import Android.support.v4.view.pageradapter;import Android.support.v4.view.viewpager;import Android.view.View;import Android.view.viewgroup.layoutparams;import Android.widget.imageview;public class Myadapter extends PagerAdapter { Public Context mcontext;public Myadapter (context mcontext) {this.mcontext = Mcontext;} To adjust the maximum number of elements set, you can infinitely right swipe, left slide cannot exceed 100,000 times @overridepublic int GetCount () {return integer.max_value;} @Overridepublic int GetItemPosition (Object object) {//TODO auto-generated method Stubreturn super.getitemposition ( object);} This everybody understands, the usage can Baidu or Oschina, I vernacular: each time initializes the current view and the left and right side view @overridepublic Object instantiateitem (view arg0, int position) {/ /TODO auto-generated method stubint posi = position% myviewpager.imageresid.length;//Each time a new view is added, it is a bit resource-intensive, but there is no conflict. And in the process of view switching, useless views are destroyed. ImageView Ximageview = new ImageView (mcontext); Ximageview.setbackgroundresource (Myviewpager.imageresid[posi]); Android.view.ViewGroup.LayoutParams para = new Android.view.ViewGroup.LayoutParams (layoutparams.wrap_content, layoutparams.wrap_content); Ximageview.setadjustviewbounds (True); Ximageview.setlayoutparams (para);((viewpager) arg0). AddView (Ximageview, 0); return Ximageview;} @Overridepublic void Destroyitem (view arg0, int position, Object arg2) {//Destroy unwanted views ((Viewpager) arg0). Removeview (view) a RG2);} @Overridepublic boolean isviewfromobject (View arg0, Object arg1) {return arg0 = = arg1;} @Overridepublic void Restorestate (parcelable arg0, ClassLoader arg1) {} @Overridepublic parcelable saveState () {return null;} @Overridepublic void Startupdate (view arg0) {} @Overridepublic void Finishupdate (view arg0) {}}

Code URL: http://pan.baidu.com/s/1pJMDVMb

How does Android implement the status of the wireless loop slide of the focus graph?