android - Set the child view at the TopLeft and BottomRight in a viewgroup -

in application have layout this:

1) main view can moved , dragged.

2) controllers can added inside main view. , position can set topleft or else. topleft here means relative main view.(see this image)

now tried implement extending viewgroup, , main view , controllers extends view.

this have done now:

class myviewcontainer extends viewgroups{    @override    public void onlayout(boolean changed,int l,int t,int b, int r){        for(int i=0,len=getchildcounts,i<len;i++){         view v=getchildat(i);         if(v instanceof mainview){            v.layout(l,t,b,r);         }         else if(v instanceof mycontroller){           //here not know how layout childs according position         }       }    } } abstract mycontroller extends view{ } class zoomcontroller extends mycontroller{     @override     public void ondraw(canvas c){      } } class anothercontroller extends mycontroller{     @override     public void ondraw(canvas c){      } } class mainview extends view{     @override     public void ondraw(canvas c){      } } 

as can see, have no idea layout mycontrollers. since not know width , height of controller. beacuse size of controllers depended on how being drawn.

how make it?

try this. work, master view has come before controllers.

class myviewcontainer extends viewgroups{     @override     public void onlayout(boolean changed,int l,int t,int b, int r){         view masterview = null;         for(int i=0,len=getchildcounts,i<len;i++){             view v=getchildat(i);             if(v instanceof mainview){                 masterview = v;                 v.layout(l,t,b,r);             }             else if(v instanceof mycontroller){                 // layout views here.                 relativelayout.layoutparams params = new relativelayout.layoutparams(layoutparams.wrap_content, layoutparams.wrap_content);                 if (masterview != null && topleft) {                     params.addrule(relativelayout.align_left, masterview.getid());                     params.addrule(relativelayout.align_top, masterview.getid());                 }                 if (masterview != null && bottomright) {                     params.addrule(relativelayout.align_right, masterview.getid());                     params.addrule(relativelayout.align_bottom, masterview.getid());                 }                 v.setlayoutparams(params);             }         }     } }