android: stretch image in imageview to fit screen
to change pro-grammatically use :
imgview.setScaleType(ScaleType.FIT_XY);
OR
to change from xml use:
android:scaleType="fitXY"
Give in the xml file of your layout android:scaleType="fitXY"
P.S : this applies to when the image is set with android:src="..." rather than android:background="..." as backgrounds are set by default to stretch and fit to the View.