Android custom dialog height -

i'm learning android dialogs , i'm confused determines height. if use xml dialog layout . . .

<?xml version="1.0" encoding="utf-8"?> <relativelayout   xmlns:android="http://schemas.android.com/apk/res/android"   android:layout_width="wrap_content"   android:layout_height="wrap_content">   <button      android:id="@+id/abutton"      android:layout_height="wrap_content"      android:layout_width="wrap_content"      android:layout_alignparentright="true"      android:layout_marginleft="10px"      android:text="click me dismiss"   />    <textview android:id="@+id/text"     android:layout_width="wrap_content"     android:layout_height="fill_parent"     android:layout_toleftof="@id/abutton"     android:text="click button: "      />    <imageview     android:id="@+id/an_image"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:layout_marginleft="42px"     android:src="@drawable/screw50">   </imageview>         /> 

i dialog . . .

but developer.android.com says that...

"wrap_content, means view wants big enough enclose content (plus padding)"

... why dialog higher needs be?

if replace layout height

  android:layout_height="200px" 

it makes short dialog don't want use explicit pixel heights (it's not practice). how make dialog big enough content?

you have height of textview fill_parent. possible this, combined height of relativelayout wrap_content pushing height maximum size? happens if change textview height wrap_content?

to add, the android sdk says children of relativelayout can not have dependency on layout, such align_parent_bottom. assume fill_parent dependency , breaking layout.