Android: Setting Window Background on launched Act

Question

So I've read Romain Guy's blog post on setting the Window background and percieved performance, and am trying to emulate that. It is such a simple solution and not sure why I can't get this working, but the activity simply refuses to pick-up the directed background.

I have a ListView that onListItemClick launches a new Activity, one that takes 3-5 seconds to fully load. While the user is waiting, I'd like to draw a windowBackground so that they 'see' the activity before it is actually ready. Here's my code:

AndroidManifest snippet for the launched Activity:

<activity 
        android:name=".activity.EditorActivity"
        android:screenOrientation="portrait"
        android:windowBackground="@drawable/background_editor">

The XML layout for the EditorActivity:

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView 
    android:id="@+id/editor"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:text="Editor" />
</FrameLayout>

And finally, the drawable being set in the Manifest, background_editor.xml:

<?xml version="1.0" encoding="utf-8"?>
<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
    android:src="@drawable/editor_bg"
    android:tileMode="repeat" />

editor_bg is a .png file located int he drawable folder.

The end result is the EditorActivity gets launched, and all I see is the default black background with the "Editor" text displayed in white (I added that to test that the XML file was loading correctly.

I've also tried setting the background of the FrameLayout and TextView to transparent via android:background="@android:color/transparent", thinking maybe they were defaulting to a black background, but no luck.

It's been a long few days, I'm sure I am missing something simple... any obvious mistakes I am making here?

Answer 1

it works for me if i declared this in a Theme Style in styles.xml :

<?xml version="1.0" encoding="utf-8"?>
<resources xmlns:android="http://schemas.android.com/apk/res/android"   
xmlns:app="http://schemas.android.com/apk/res-auto">

    <style name="CustomTheme" parent="android:Theme.Holo.NoActionBar">
        <item name="android:windowBackground">@color/bg_evening</item>
    </style>

</resources>

and in the manifest i set this theme to my application :

<application
    android:name="com.my_app.pack"
    android:theme="@style/CustomTheme" >
...

or to one of my activities :

<activity
    android:name="..."
    android:theme="@style/CustomTheme">
...

you can declare muliple theme styles and add any one of them to any of your activities, which will override the theme set to the application

Answer 2

Try setting window background before launching the new activity programmatically.

getWindow().setBackgroundDrawableResource(R.drawable.my_drawable);

Answer 3

I have ran into the same problem and wasted my day on it. We can't set the theme in java as in my case the control came to onCreate of my splash activity very late. Till that time black screen keep visible.

This gave me clue that window has to be managed from theme which we specify in manifest.

There is the manifest i have:

<activity
        android:name=".main.activities.SplashScreen"
        android:theme="@style/Splash"
        android:screenOrientation="portrait">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
</activity>

Now The theme i created is as follows:

<style name="Splash" parent="@style/Theme.AppCompat.Light">
    <item name="android:windowBackground">@drawable/splash</item>
    <item name="android:windowNoTitle">true</item>
    <item name="windowNoTitle">true</item>
    <item name="colorPrimaryDark">@color/green_09</item>
    <item name="colorPrimary">@color/green_09</item>
    <item name="windowActionBar">false</item>
</style>

Splash in the drawable resource which contains a bitmap resource, I have to tweak a bit to make it look perfect not stretched and in center:

<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
    android:antialias="true"
    android:dither="true"
    android:gravity="fill"
    android:src="@drawable/splash_screen" />