android - How to know whether View inside Scroll is Visible completely or no -

there scroll view between header(at top of screen) , tabs(bottom of screen). want know whether imageview inside scrollview visible or not on phone screen window.

i suggest following way (the approach similar 1 in this question).

e.g. have following xml (i'm not sure header , tabs missed):

<scrollview     xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_height="match_parent"     android:layout_width="match_parent"     android:id="@+id/scroller">         <imageview             android:layout_height="wrap_content"             android:layout_width="wrap_content"             android:layout_gravity="center"             android:id="@+id/image"             android:src="@drawable/image001"             android:scaletype="fitxy" /> </scrollview> 

then activity might following:

public class myactivity extends activity {      private static final string tag = "myactivity";      private scrollview mscroll = null;     private imageview mimage = null;      private viewtreeobserver.ongloballayoutlistener mlayoutlistener = new viewtreeobserver.ongloballayoutlistener() {         @override         public void ongloballayout() {             final rect imagerect = new rect(0, 0, mimage.getwidth(), mimage.getheight());             final rect imagevisiblerect = new rect(imagerect);              mscroll.getchildvisiblerect(mimage, imagevisiblerect, null);              if (imagevisiblerect.height() < imagerect.height() ||                     imagevisiblerect.width() < imagerect.width()) {                 log.w(tag, "image not visible");             } else {                 log.w(tag, "image visible");             }              mscroll.getviewtreeobserver().removeongloballayoutlistener(mlayoutlistener);         }     };      @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);          // show layout test view         setcontentview(r.layout.main);          mscroll = (scrollview) findviewbyid(r.id.scroller);         mimage = (imageview) findviewbyid(r.id.image);          mscroll.getviewtreeobserver().addongloballayoutlistener(mlayoutlistener);     } } 

in case of small image log: image visible.

however, should aware following inconsistency (as per understanding): if have big image, doing scaling (e.g. set android:layout_width="wrap_content") when scaled, actual imageview height full height of image (and scrollview scrolling), adjustviewbounds might needed. reason behavious framelayout doesn't care layout_width , layout_height of childs.