Android PIN 或模式更改监听器

Question

我有一个 Android 应用程序，它显示一个图标，上面写着“设备应使用 PIN 或模式进行保护”。然后用户转到“设置”并为其设备启用 PIN 码或图案，然后返回到应用程序。仍然显示该图标。我如何监听此事件并禁用图标？

该图标仅在应用终止并重新启动后消失。

Answer 1

我认为没有针对此类问题的任何事件监听器。

你可以做的是你可以在每次应用onResume()时检查它。

通过对以下代码进行一些操作。

public class LockType
{
    private final static String PASSWORD_TYPE_KEY = "lockscreen.password_type";

    /**
     * This constant means that android using some unlock method not described here.
     * Possible new methods would be added in the future releases.
     */
    public final static int SOMETHING_ELSE = 0;

    /**
     * Android using "None" or "Slide" unlock method. It seems there is no way to determine which method exactly used.
     * In both cases you'll get "PASSWORD_QUALITY_SOMETHING" and "LOCK_PATTERN_ENABLED" == 0.
     */
    public final static int NONE_OR_SLIDER = 1;

    /**
     * Android using "Face Unlock" with "Pattern" as additional unlock method. Android don't allow you to select
     * "Face Unlock" without additional unlock method.
     */
    public final static int FACE_WITH_PATTERN = 3;

    /**
     * Android using "Face Unlock" with "PIN" as additional unlock method. Android don't allow you to select
     * "Face Unlock" without additional unlock method.
     */
    public final static int FACE_WITH_PIN = 4;

    /**
     * Android using "Face Unlock" with some additional unlock method not described here.
     * Possible new methods would be added in the future releases. Values from 5 to 8 reserved for this situation.
     */
    public final static int FACE_WITH_SOMETHING_ELSE = 9;

    /**
     * Android using "Pattern" unlock method.
     */
    public final static int PATTERN = 10;

    /**
     * Android using "PIN" unlock method.
     */
    public final static int PIN = 11;

    /**
     * Android using "Password" unlock method with password containing only letters.
     */
    public final static int PASSWORD_ALPHABETIC = 12;

    /**
     * Android using "Password" unlock method with password containing both letters and numbers.
     */
    public final static int PASSWORD_ALPHANUMERIC = 13;

    /**
     * Returns current unlock method as integer value. You can see all possible values above
     * @param contentResolver we need to pass ContentResolver to Settings.Secure.getLong(...) and
     *                        Settings.Secure.getInt(...)
     * @return current unlock method as integer value
     */
    public static int getCurrent(ContentResolver contentResolver)
    {
        long mode = android.provider.Settings.Secure.getLong(contentResolver, PASSWORD_TYPE_KEY,
                DevicePolicyManager.PASSWORD_QUALITY_SOMETHING);
        if (mode == DevicePolicyManager.PASSWORD_QUALITY_SOMETHING)
        {
            if (android.provider.Settings.Secure.getInt(contentResolver, Settings.Secure.LOCK_PATTERN_ENABLED, 0) == 1)
            {
                return LockType.PATTERN;
            }
            else return LockType.NONE_OR_SLIDER;
        }
        else if (mode == DevicePolicyManager.PASSWORD_QUALITY_BIOMETRIC_WEAK)
        {
            String dataDirPath = Environment.getDataDirectory().getAbsolutePath();
            if (nonEmptyFileExists(dataDirPath + "/system/gesture.key"))
            {
                return LockType.FACE_WITH_PATTERN;
            }
            else if (nonEmptyFileExists(dataDirPath + "/system/password.key"))
            {
                return LockType.FACE_WITH_PIN;
            }
            else return FACE_WITH_SOMETHING_ELSE;
        }
        else if (mode == DevicePolicyManager.PASSWORD_QUALITY_ALPHANUMERIC)
        {
            return LockType.PASSWORD_ALPHANUMERIC;
        }
        else if (mode == DevicePolicyManager.PASSWORD_QUALITY_ALPHABETIC)
        {
            return LockType.PASSWORD_ALPHABETIC;
        }
        else if (mode == DevicePolicyManager.PASSWORD_QUALITY_NUMERIC)
        {
            return LockType.PIN;
        }
        else return LockType.SOMETHING_ELSE;
    }

    private static boolean nonEmptyFileExists(String filename)
    {
        File file = new File(filename);
        return file.exists() && file.length() > 0;
    }
}