Question

I have the following application.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.currency.mobile.android">
    <uses-permission android:name="android.permission.INTERNET"/>
    <application android:icon="@drawable/icon" android:label="@string/app_name"
                 android:theme="@android:style/Theme.Light.NoTitleBar">

        <activity android:name=".MainActivity" android:noHistory="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

        <activity android:name=".LoginActivity"/>
        <activity android:name=".HomeActivity" />
        <activity android:name=".FriendsActivity"/>
        <activity android:name=".PlacesActivity"/>
        <activity android:name=".ProfileActivity"/>
        <activity android:name=".PurchasesActivity"/>
    </application>
</manifest>

This is my tab view:

<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
         android:id="@android:id/tabhost"
         android:layout_width="fill_parent"
         android:layout_height="fill_parent">
    <LinearLayout
            android:orientation="vertical"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:padding="5dp">
        <TabWidget
                android:id="@android:id/tabs"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"/>
        <FrameLayout
                android:id="@android:id/tabcontent"
                android:layout_width="fill_parent"
                android:layout_height="fill_parent"
                android:padding="5dp"/>
    </LinearLayout>
</TabHost>

When using Theme.Light.NoTitleBar I get this ugly line in the middle:

But when I use Theme.Black it doesn’t have such a weird line. Any way to fix it so that I can use light theme?

Answer 1

That’s actually the theme’s frame (or possibly the overlay, i can never remember which one specifically), and Android applies it to activities even when they’re nested inside tabs. The trick is to set a Theme (in res/value/theme.xml) with the windowFrame and windowContentOverlay properties set to @null on the container activity, like this one:

<style
    name="Theme.Light.NoFrame"
    parent="android:Theme.Light">
    <item
        name="android:windowFrame">@null</item>
    <item
        name="android:windowContentOverlay">@null</item>
</style>

I also recommend digging through style.xml and theme.xml in the AOSP to find out more; themes and styles are severely underdocumented but pretty easy to understand by just reading the source.