android - can't set alertdialog size -

i have problem alertdialog has fixed max size perfect square side length of min(parent width, parent height). creates problem can't alertdialog wide screen.

in dialog, have loaded imageview show image. want image shown wide screen , not in square - makes smaller.

code alertdialog in acivity:

alertdialog.builder alertadd = new alertdialog.builder(mainactivity.this); layoutinflater factory = layoutinflater.from(mainactivity.this); final view view = factory.inflate(r.layout.schematic_image_view, null); alertadd.setview(view); alertadd.show(); 

code xml file schematic_image_view.xml:

<linearlayout      xmlns:android="http://schemas.android.com/apk/res/android"     android:id="@+id/layout_root"      android:orientation="horizontal"     android:layout_width="match_parent"      android:layout_height="match_parent"     android:padding="0dp">      <imageview           android:id="@+id/schematic"           android:layout_width="match_parent"          android:layout_height="match_parent"          android:scaletype="fitxy"          android:src="@drawable/schematic">     </imageview>