Android API 版本兼容问题

Android

Android App 中targetSdkVersion的作用

加密算法的变动:

 SecureRandom sr = SecureRandom.getInstance(SHA1, CRYPTO);

public static SecureRandom getInstance(String algorithm, String provider)
        throws NoSuchAlgorithmException, NoSuchProviderException {
    try {
        Instance instance = GetInstance.getInstance("SecureRandom",
                SecureRandomSpi.class, algorithm, provider);
        return new SecureRandom((SecureRandomSpi) instance.impl,
                instance.provider, algorithm);
    } catch (NoSuchProviderException nspe) {
        if ("Crypto".equals(provider)) {
            System.logE(" ********** PLEASE READ ************ ");
            System.logE(" * ");
            System.logE(" * New versions of the Android SDK no longer support the Crypto provider.");
            System.logE(" * If your app was relying on setSeed() to derive keys from strings, you");
            System.logE(" * should switch to using SecretKeySpec to load raw key bytes directly OR");
            System.logE(" * use a real key derivation function (KDF). See advice here : ");
            System.logE(" * http://android-developers.blogspot.com/2016/06/security-crypto-provider-deprecated-in.html ");
            System.logE(" *********************************** ");
            // Target SDK <= 23 时使用旧版本的功能
            if (VMRuntime.getRuntime().getTargetSdkVersion()
                    <= sdkTargetForCryptoProviderWorkaround) {
                System.logE(" Returning an instance of SecureRandom from the Crypto provider");
                System.logE(" as a temporary measure so that the apps targeting earlier SDKs");
                System.logE(" keep working. Please do not rely on the presence of the Crypto");
                System.logE(" provider in the codebase, as our plan is to delete it");
                System.logE(" completely in the future.");
                return getInstanceFromCryptoProvider(algorithm);
            }
        }
        throw nspe;
    }
}

support library 变动

• v7 Toolbar 的Button对齐属性，在v7 support 24以前不能设置
  mButtonGravity = a.getInteger(R.styleable.Toolbar_buttonGravity, Gravity.TOP);