<ImageButton

            android:id="@+id/tv3"

            android:layout_width="150dp"

            android:layout_height="150dp"

            android:layout_marginTop="20dp"

            android:src="@drawable/ic_alarm"

            android:background="#ff0000" />

        imagebutton.setBackgroundResource(R.drawable.ic_alarm);

        imagebutton.setImageResource(R.drawable.ic_alarm);

//得到src

Drawable drawable = imageView.getDrawable();

//得到background

Drawable drawable2 = imageView.getBackground();