MarketUnknownSourceInformation.java

public class MarketUnknownSourceInformation {
    public static boolean getMarketUnknownSourceInformation() {
        boolean unknownSource = false;
        if (Build.VERSION.SDK_INT < 3) {
            unknownSource = Settings.System.getInt(getContentResolver(), 
                                                   Settings.System.INSTALL_NON_MARKET_APPS, 0) == 1;
  } else if (Build.VERSION.SDK_INT < 17) {
            unknownSource = Settings.Secure.getInt(getContentResolver(), 
                                                   Settings.Secure.INSTALL_NON_MARKET_APPS, 0) == 1;
        } else {
            unknownSource = isInstallNowMarketApps();
        }
 
        return unknownSource;
    }
 
    @TargetApi(17)
    private static boolean isInstallNowMarketApps() {
        return Settings.Global.getInt(getContentResolver(), Settings.Global.INSTALL_NON_MARKET_APPS, 0) == 1;
    }
}