java - Clicking an ImageButton to change to a different image everytime -

i have imagebutton, false appears gray image, while true appears green image. if use state_pressed="true" , state_pressed="false" function work, need hold left-click button button change true.

p.s: believe using wrong state have tried others didn't work.

my question is: how keep image true clicking once on imagebutton?

code:

<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:drawable="@drawable/green_clock" android:state_selected= "true"> </item> <item android:drawable="@drawable/grey_clock" android:state_selected="false"> </item> </selector>

java file:

public void onclickclock(view v) {     imagebutton clockbtn = (imagebutton)findviewbyid(r.id.clock);     clockbtn.setimageresource(r.drawable.clock); } 

activity.xml:

<imagebutton     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:id="@+id/clock"     android:src="@drawable/clock"     android:background="@android:color/transparent"     android:layout_alignparenttop="true"     android:layout_alignparentright="true"     android:layout_alignparentend="true"     android:layout_margintop="73dp"     android:onclick="onclickclock" /> 

thanks!

add setselected()

public void onclickclock(view v) {     imagebutton clockbtn = (imagebutton)findviewbyid(r.id.clock);     clockbtn.setselected(!clockbtn.isselected()); }