Picture going outside the phones screen
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 I am trying to make an image application and i have a button and and image view in one of my xml files.  I have a default picture on the image view. On some devices its to small or its too big. I dont want the picture to go outside the screen or over the button.  How would i do this?
here is the xml code

    <Button
        android:id="@+id/btakePic"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentLeft="true"
        android:text="Take Picture" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="fill_parent"
        android:layout_height="400dp"
        android:gravity="center"
        android:src="@drawable/android_syh" />

