Setting android:windowBackground to @null makes scrolling to smear?

问题

i'm using the sherlock actionbar library in order to support many devices . i have a viewPager which has 3 fragments :

• one with a listView , each item has a textView and an imageView
• the second has a gridView , each item has a textView and an imageView
• the third just has a textView for now.

as i've heard in google IO videos (and since Lint tells me) , it's recommended to have the next style being used for all of the activities:

<resources xmlns:android="http://schemas.android.com/apk/res/android">

  <style name="AppTheme" parent="@style/Theme.Sherlock">
    <item name="android:windowBackground">@null</item>
  </style>

</resources>

this has worked for me on many devices .

however , on the emulator , using version 2.3.3 , and on galaxy nexus , when i scroll (either the viewPager or any of the adapterViews) , everything just smears , so i get a lot of white pixels as if nothing was refreshed.

i've even tried to set android:cacheColorHint="#00000000" for all of my adapterViews , but it still occurs.

what is going on? how can i fix this thing ? i like adding the above since it removes the ugly gradient background of galaxy S3 that appears for every app.

回答1:

You should only set the background to nul if you cover it with something else. Either: - Set the background to null in the theme and add a new background in your layout or - Set the background in your theme to the color/image you want.

来源：https://stackoverflow.com/questions/12150761/setting-androidwindowbackground-to-null-makes-scrolling-to-smear