I have used config.xml to configure my app.

    <preference name="AutoHideSplashScreen" value="true" />
        <preference name="BackupWebStorage" value="cloud" />
        <preference name="DisallowOverscroll" value="false" />
        <preference name="EnableViewportScale" value="false" />
        <preference name="FadeSplashScreen" value="true" />
        <preference name="FadeSplashScreenDuration" value=".25" />
        <preference name="KeyboardDisplayRequiresUserAction" value="true" />
        <preference name="MediaPlaybackRequiresUserAction" value="false" />
        <preference name="ShowSplashScreenSpinner" value="true" />
        <preference name="SuppressesIncrementalRendering" value="false" />
        <preference name="TopActivityIndicator" value="gray" />
        <preference name="GapBetweenPages" value="0" />
        <preference name="PageLength" value="0" />
        <preference name="PaginationBreakingMode" value="page" />
        <preference name="PaginationMode" value="unpaginated" />

But it has no effect on the code.
could any body tell me please.
why cordova config.xml does not work on ionic ?


I think you will need to provide more details. What exactly is not working?


and also provide us of how you test it and does you test it on Android or iOS, remember the more information you give the better help you get.

also is this the main config.xml file or its specific to Android, iOS … etc.


Yes, this is the main config.xml .
I made TopActivityIndicator to gray but is not converting to.
after made the main config.xml i use this command. “ionic build iOS”


I think you are doing it wrong, the main config.xml should only have the options which belongs to all the platforms, so here you have 2 options :
1- to add your options to the iOS config.xml file ( ).
2- to wrap your config preference which belongs to iOS inside the platform tag for example :

<platform name="android">
    <preference name="Fullscreen" value="true" />

the above code will only work for android, you should check the others for iOS.

hopefuly this will help