java - Android - How to start a new activity -

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i'm trying make bull's eye random color, , instead of circles use squares.

but thing when run app on emulator , when starts new activity stops responding.

this main activity, 1 starts drawactivity.

public class mainactivity extends activity {      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);          intent coiso = new intent(this, draw.class);         startactivity(coiso);     }      @override     public boolean oncreateoptionsmenu(menu menu) {         // inflate menu; adds items action bar if present.         getmenuinflater().inflate(r.menu.main, menu);         return true;     } }

and draw activity, 1 want start. (it doesn't have things want do. because can't, problem ahead) 

public class draw extends view {      public draw(context context) {         super(context);         // todo auto-generated constructor stub     }      @override     protected void ondraw(canvas canvas) {         // todo auto-generated method stub         super.ondraw(canvas);        } }

can me? sorry english.

you have this

 public class draw extends view

your class not extend activity

instead can below

draw draw = new draw(this);  setcontentview(draw);

or have layout linear or relative , place add draw view layout after initializing.

setcontentview(r.layout.activity_main); linearlayout ll = (linearlayout)findviewbyid(r.id.linearlayout); // linear layout or relative layout in activity_main.xml. // place layout ahere want along other views   draw draw = new draw(this);  ll.addview(draw);   // add customview linearlayout

edit:

remove this

 intent coiso = new intent(this, draw.class);  startactivity(coiso);

in activity_main.xml

<?xml version="1.0" encoding="utf-8"?> <relativelayout xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_width="fill_parent"     android:layout_height="fill_parent" >      // customize linear layout needs.      <linearlayout         android:layout_width="200dp"         android:layout_height="200dp"         android:id="@+id/linearlayout"         android:orientation="vertical" >     </linearlayout>       // other widgets </relativelayout>

in oncreate

setcontentview(r.layout.activity_main); linearlayout ll = (linearlayout)findviewbyid(r.id.linearlayout); draw draw = new draw(this);  ll.addview(draw);

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