Android Learning Scroller (i)

Mainactivity as follows:

Package Cc.cn;import Android.os.bundle;import Android.view.view;import android.view.view.onclicklistener;import Android.widget.button;import android.app.activity;/** * Demo Description: * Scroller Use example-let the control pan across the screen * reference: * HTTP://BLOG.CSDN.N et/c_weibin/article/details/7438323 * Thank you very much * * NOTE: * 1 Set the width of the Cc.cn.LinearLayoutSubClass control in the layout to "Fill_par    ENT "* Easy to observe the effect of sliding */public class Mainactivity extends Activity {private Button Mbutton; Private Linearlayoutsubclass mlinearlayoutsubclass; @Overrideprotected void OnCreate (Bundle savedinstancestate) { Super.oncreate (savedinstancestate); Setcontentview (R.layout.main); init ();} private void Init () {mlinearlayoutsubclass= (Linearlayoutsubclass) Findviewbyid (r.id.linearlayoutsubclass); mButton= (Button) Findviewbyid (R.id.button), Mbutton.setonclicklistener (new Onclicklistener () {@Overridepublic void OnClick ( View view) {Mlinearlayoutsubclass.beginscroll ();}});}}

Linearlayoutsubclass as follows:

Package Cc.cn;import Android.content.context;import Android.util.attributeset;import android.widget.LinearLayout; Import android.widget.scroller;/** * API NOTE: * * 1//First, two parameter start position; third, four scrolling offset; fifth parameter duration * Startscroll (int startX, int sta rty, int dx, int dy, int duration) * * 2//During the execution of the Startscroll () method The Computescrolloffset () * method will always return true during the duration time, but when the animation Returns False when execution is complete.  * Computescrolloffset () * * 3 when executing ontouch () or invalidate () or postinvalidate () will call the method * Computescroll () * */public class Linearlayoutsubclass extends LinearLayout {private Scroller mscroller;private boolean flag=true;public Linearlayoutsubclass (Context context) {super (context);} Public Linearlayoutsubclass (context context, AttributeSet Attrs) {Super (context, attrs);//You can also use this construction method to pass in a interpolator/ /mscroller=new Scroller (context, interpolator); mscroller=new Scroller (context);} @Overridepublic void Computescroll () {super.computescroll (); if (Mscroller.computescrolloffset ()) {ScrollTo ( Mscroller.getcurrx (), 0);//Make It call again Computescroll () until the end of the slide, i.e. not satisfying if condition postinvalidate ();}} public void Beginscroll () {if (flag) {mscroller.startscroll (0, 0, -2500, 0, 2500); flag = false;} else {Mscroller.startscrol L (0, 0, 0, 0,); flag = true;} Call invalidate (); Make it call Computescroll () invalidate ();}}

Main.xml as follows:

<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 "> <Butt        On android:id= "@+id/button" android:layout_width= "wrap_content" android:layout_height= "Wrap_content" Android:layout_centerhorizontal= "True" android:text= "click to Swipe"/> <cc.cn.linearlayoutsubclass A Ndroid:id= "@+id/linearlayoutsubclass" android:layout_width= "fill_parent" android:layout_height= "wrap_content            "Android:layout_centervertical=" true "> <textview android:layout_width=" wrap_content " android:layout_height= "Wrap_content" android:background= "#ff1100" android:text= "Test Scrolle R "/> </cc.cn.LinearLayoutSubClass></RelativeLayout>