For manipulating Android WindowManager LayoutParams dynamically at the application’s run-time, a Flutter plugin supports you.
While Android natively supports a variety of window modes, there was no good way to set these dynamically within a running Flutter application – instead of requiring that these flags are set within the native MainActivity of the Flutter application itself.
With our application, we only hoped to disable screenshots for specific screens, rather than across the entire application lifecycle. This can now be accomplished by simply calling:
for the relevant screen.
This can further be toggled for a specific screen by either using a
RouteAware mixin, or through direct toggling in
dispose() methods in the case of stateful widgets.
The full range of LayoutParams flags are passed through. The plugin
will carry out basic API level checking and throw an error on any
unsupported flag specification. Flags are implemented using a bitmask,
and may be specified individually or ORed together for setting/clearing
multiple flags at once.
The current list of flags is:
FLAG_ALLOW_LOCK_WHILE_SCREEN_ON FLAG_ALT_FOCUSABLE_IM FLAG_DIM_BEHIND FLAG_FORCE_NOT_FULLSCREEN FLAG_FULLSCREEN FLAG_HARDWARE_ACCELERATED FLAG_IGNORE_CHEEK_PRESSES FLAG_KEEP_SCREEN_ON FLAG_LAYOUT_INSET_DECOR FLAG_LAYOUT_IN_SCREEN FLAG_LAYOUT_NO_LIMITS FLAG_NOT_FOCUSABLE FLAG_NOT_TOUCHABLE FLAG_NOT_TOUCH_MODAL FLAG_SCALED FLAG_SECURE FLAG_SHOW_WALLPAPER FLAG_SPLIT_TOUCH FLAG_WATCH_OUTSIDE_TOUCH FLAG_BLUR_BEHIND FLAG_DISMISS_KEYGUARD FLAG_DITHER FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS FLAG_LAYOUT_ATTACHED_IN_DECOR FLAG_LAYOUT_IN_OVERSCAN FLAG_LOCAL_FOCUS_MODE FLAG_SHOW_WHEN_LOCKED FLAG_TOUCHABLE_WHEN_WAKING FLAG_TRANSLUCENT_NAVIGATION FLAG_TRANSLUCENT_STATUS FLAG_TURN_SCREEN_ON
In practice, this plugin was developed primarily for the toggling of
FLAG_SECURE. Other flags have not been tested, and we make no
guarantees that toggling with any of the other flags will interact well
with Flutter – if you find specific problems with any particular flag,
please let us know in the [issue tracker][tracker].