ImageButton btnTest = new ImageButton(this);
btnTest.setImageResource(R.drawable.title_web);
btnTest.setScaleType(ScaleType.FIT_START);
btnTest.setAdjustViewBounds(true);
btnTest.setLayoutParams(new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT));