Unable to use android:weightSum properly

Question

I'm trying to build a layout. The code is below. I'm unable to add proper weight to layouts. The code below doesn't create a layout with weights. The layout is same with and without the weights added! Forgive me if I've not explained it properly. I'm completely new to programming.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="100" >

<ScrollView
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_weight="30" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <EditText
            android:id="@+id/editText1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10" >
        </EditText>

        <TextView
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <EditText
            android:id="@+id/editText2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10" />

        <TextView
            android:id="@+id/textView3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <EditText
            android:id="@+id/editText3"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10" />

        <TextView
            android:id="@+id/textView4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <EditText
            android:id="@+id/editText4"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10" />

        <TextView
            android:id="@+id/textView5"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <EditText
            android:id="@+id/editText5"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10" />

        <TextView
            android:id="@+id/textView6"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView" />

        <EditText
            android:id="@+id/editText6"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10" />
    </LinearLayout>
</ScrollView>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="fill_parent"
    android:layout_weight="40"
    android:orientation="vertical" >

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button" />
</LinearLayout>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="fill_parent"
    android:layout_weight="30"
    android:orientation="vertical" >

    <AnalogClock
        android:id="@+id/analogClock1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
</LinearLayout>

Answer 1

Scroll View does not have Weight sum property if you want to set layout according to weight then remove Scroll View otherwise just use Scroll view you don't need weight sum in scroll view.

Answer 2

layout_weight mechanism distributes any remaining space in the layout in proportion to child weights. Your views already take up all space with fill_parent so there's no remaining space for the weight mechanism to distribute. Set the weighed layout children heights to 0px so that there is actually some space to distribute by weight.

Also, specifying the weight sum is often redundant. The layout itself can calculate the sum of child weights for you.