NativeScript: GridLayout alignment issue

I am very new to NativeScript. I am following its own document. I am trying for UI Alignment. I unable to achieve this. I am using Xcode IDE and running in iOS Simulator.

Groceries Logo should be in Top

Textfields should be in middle

Sign up button should be in Bottom

Attempt 1

<Page loaded="loaded">

<GridLayout height=auto horizontalAlignment="center" verticalAlignment="center" columns="*" rows="auto,auto,*"  backgroundColor="brown">
    <Image src="res://logo" stretch="aspectFit" horizontalAlignment="center" verticalAlignment="top" col="0" row="0"></Image>
    <GridLayout columns="*" rows="auto,auto,auto" verticalAlignment="center" backgroundColor="lightgray" col="0" row="1">

        <TextField class="userTxtFld" id="email" text="{{ email }}" hint="Email Address" keyboardType="email" autocorrect="false" autocapitalizationType="none"  col="0" row="0"/>
        <TextField secure="true" text="{{ password }}" hint="Password" col="0" row="1"/>
        <Button text="Sign in" tap="signIn"  col="0" row="2"/>

    </GridLayout>
    <Button text="Sign up for Groceries" class="link" tap="register" verticalAlignment="bottom" col="0" row="2"/>
</GridLayout>
</Page>

Attempt 2

<Page loaded="loaded">

<GridLayout height="auto" horizontalAlignment="center" verticalAlignment="center" columns="*" rows="auto,auto,*"  backgroundColor="brown">
    <Image src="res://logo" stretch="aspectFit" horizontalAlignment="center" verticalAlignment="top" col="0" row="0"></Image>
    <GridLayout columns="*" rows="auto,auto,auto" verticalAlignment="center" backgroundColor="lightgray" col="0" row="1">

        <TextField class="userTxtFld" id="email" text="{{ email }}" hint="Email Address" keyboardType="email" autocorrect="false" autocapitalizationType="none"  col="0" row="0"/>
        <TextField secure="true" text="{{ password }}" hint="Password" col="0" row="1"/>
        <Button text="Sign in" tap="signIn"  col="0" row="2"/>

    </GridLayout>
    <Button text="Sign up for Groceries" class="link" tap="register" verticalAlignment="bottom" col="0" row="2"/>
</GridLayout>
</Page>

Issue

In attempt 1, height=auto and in attempt 2, height="auto"

I need output as Attempt 1.

I dont know, why backgroundcolor is not displaying in height=auto

I dont know, why UI Alignment is not fixing in height="auto"

If height="auto" is right way, how to do get output as Attempt 1?

Kindly help me this.

Output

if you want first row to be top,second to be middle and last one to be at bottom then you should use rows="auto,*,auto" which will do that exactly.

try this

<Page loaded="loaded">

<GridLayout height="100%" horizontalAlignment="center" verticalAlignment="center" columns="*" rows="auto,*,auto"  backgroundColor="brown">
    <Image src="res://logo" stretch="aspectFit" horizontalAlignment="center" verticalAlignment="top" col="0" row="0"></Image>
    <GridLayout columns="*" rows="auto,auto,auto" verticalAlignment="center" backgroundColor="lightgray" col="0" row="1">

        <TextField class="userTxtFld" id="email" text="{{ email }}" hint="Email Address" keyboardType="email" autocorrect="false" autocapitalizationType="none"  col="0" row="0"/>
        <TextField secure="true" text="{{ password }}" hint="Password" col="0" row="1"/>
        <Button text="Sign in" tap="signIn"  col="0" row="2"/>

    </GridLayout>
    <Button text="Sign up for Groceries" class="link" tap="register" verticalAlignment="bottom" col="0" row="2"/>
</GridLayout>
</Page>

same output can also be achieve by using assigning same row number to all 3 rows and using rows="*".

like this.

<Page loaded="loaded">

<GridLayout height="100%" horizontalAlignment="center" verticalAlignment="center" columns="*" rows="*"  backgroundColor="brown">
    <Image src="res://logo" stretch="aspectFit" horizontalAlignment="center" verticalAlignment="top" col="0" row="0"></Image>
    <GridLayout columns="*" rows="auto,auto,auto" verticalAlignment="center" backgroundColor="lightgray" col="0" row="0">

        <TextField class="userTxtFld" id="email" text="{{ email }}" hint="Email Address" keyboardType="email" autocorrect="false" autocapitalizationType="none"  col="0" row="0"/>
        <TextField secure="true" text="{{ password }}" hint="Password" col="0" row="1"/>
        <Button text="Sign in" tap="signIn"  col="0" row="2"/>

    </GridLayout>
    <Button text="Sign up for Groceries" class="link" tap="register" verticalAlignment="bottom" col="0" row="0"/>
</GridLayout>
</Page>

by assigning same row number row="0" they will overlap to each other taking full height because of rows="*". now we will set verticalAllignment of respective row to set it's position on top,bottom or center.