HyperDesktop Unlock

An LSPosed module that turns an external monitor into a separate display (not a mirror) on Xiaomi phones running HyperOS 4 (Android 17), where Xiaomi ships all of Android's connected-display / desktop code but keeps it disabled.

Tested on Xiaomi 15 (dada), HyperOS 4 beta based on Android 17, with a Dell S2725QC over USB-C (DisplayPort Alt Mode).

Italiano in fondo.

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What you get

• The native Android 17 "Connect to external display" dialog gains back its hidden Desktop button (Xiaomi labels it "Computer").
• Choosing it makes the monitor a real second display: its own status bar, mouse cursor, apps launched on it stay on it. No more 1:1 mirroring.
• Xiaomi's enforcer that silently re-enables mirroring is neutralised.
• Tick "Don't ask again" and the phone goes straight to desktop on every connect.
• With a dock app: the dock starts on the monitor by itself, the phone screen turns off, and Alt+Tab, monitor screenshots and other desktop keyboard shortcuts work. All of it can be changed in the module's settings app.
• Optional: the phone becomes a touchpad for the monitor (its screen stays black), with a real system pointer, tap to click, two-finger scroll and right click. Without a physical keyboard, the on-screen keyboard appears on the phone below the touchpad.
• Quick Settings tiles: Monitor (Computer ↔ Mirroring without unplugging) and Touchpad.
• A diagnostics report in the settings app, ready to paste into a GitHub issue.

Pair it with a secondary-display launcher such as SmartDock (recommended, works very well) or Taskbar to get a start menu, taskbar, app switching and Back/Home buttons on the monitor.

What you don't get (yet)

• AOSP desktop window decorations (title bar, free resizing, snapping). Xiaomi's SystemUI does not expose them, and forcing the framework gates crashed SystemUI on HyperOS 4 beta with no benefit.
• Resizable windows. HyperOS can only turn apps into its fixed-size, phone-shaped "floating windows", so apps run full screen on the monitor. (The experimental code for both is in the project history, tag v1.4.1.)
• A launcher on the monitor. HyperOS Home is single-display; use SmartDock/Taskbar.

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How it works

Everything needed is already in the firmware; Xiaomi disables it in four places. The module hooks each one (see app/src/main/java/.../):

Hook	Process	What Xiaomi did	What the module does
ConnectDialogHooks	SystemUI	In ExternalDisplayConnectionDialogDelegate the Desktop button (R.id.start_desktop_mode) is set GONE and its click listener is never attached	Makes it visible, clickable, and wires the original onStartDesktopClickListener from the ViewModel → enableForDesktop()
SettingsGuardHooks	system_server	3 ms after SystemUI writes Settings.Secure.mirror_built_in_display = 0, the framework writes it back to 1	Blocks writes of 1 coming from system_server (user choices from SystemUI/Settings still work); also protects force_desktop_mode_on_external_displays / enable_freeform_support from being reset
MirrorPolicyHooks	system_server	com.android.server.display.SecondaryDisplayPolicy (not AOSP) forces mirroring from DisplayManagerService$SettingsObserver.onChange	forceEnableMirrorBuiltInDisplaySettingIfNeeded() and enableMirrorBuiltInDisplaySetting() become no-ops
DesktopModeHooks	SystemUI + system_server	DesktopModeStatus.isDesktopModeSupported/canEnterDesktopMode are false; DesktopModeFlags.getToggleOverride() is OVERRIDE_UNSET (the "Enable desktop experience" developer option is hidden)	Forces them to true / OVERRIDE_ON; per-display checks (…OnDisplay(displayId)) only for displays other than the phone's. The framework's global DesktopModeHelper gates are left alone
LauncherHooks	SystemUI	HyperOS Home is single-display, so the monitor stays empty	When the Desktop choice is applied (applyConnectionChoice(enableMirroring=false), dialog or Don't ask again), launches the dock's desktop activity (SECONDARY_HOME, e.g. SmartDock SecondaryLauncherActivity) on the external display via ActivityOptions.setLaunchDisplayId, then any extra apps you listed in the settings. It first waits (up to 15 s) until the dock's accessibility service is connected: opening a dock activity on the monitor moves the whole app to the monitor's configuration, and SmartDock's service crashes if that change reaches it while it is starting (seen on the first connection after a reboot). Dock package from the settings (default cu.axel.smartdock)
PhoneScreen (+ ExternalDisplayGate)	system_server	Pressing power puts the whole device to sleep, monitor included	~2 s after an external physical display becomes a desktop display, turns off only the phone's panel (SurfaceControl.setDisplayPowerMode(internalToken, OFF), same technique as scrcpy --turn-screen-off), or, with the touchpad option, keeps it on but black (see Touchpad); waits for unlock if the phone is locked; restores it when the cable is unplugged, on Win+P and on an incoming call. Once per connection: lock + wake the phone to get its screen back. Virtual displays (screen recording, cast) are ignored
ModuleControl	system_server + SystemUI	—	Answers the settings app and the Quick Settings tiles: a signature-permission ordered broadcast, targeted at android and then com.android.systemui, returns status, the [diag] line and recent log lines kept in memory (XLog); also switches Computer ↔ Mirroring (mirror_built_in_display, bypassing the module's own guard for that write only) and the touchpad
Touchpad + VirtualMouse	system_server	With the panel powered off the touch sensor sleeps too, and injected mouse events reach apps but don't move the visible pointer	Keeps the panel on under an opaque black, non-focusable TYPE_SYSTEM_ERROR window (above status/navigation bars; on OLED black pixels are off at any brightness, and forcing brightness to 0 would put the touch sensor in low-power mode). Touches are read directly from the touchscreen driver (/dev/input/eventN, path and raw axes taken from InputReader's state; RawTouch), because HyperOS cancels the touch stream at the window as soon as the virtual mouse moves; the window's own touches are only a fallback. They drive a virtual HID mouse created through /dev/uhid (like scrcpy --mouse=uhid) and tied to the monitor's display (addUniqueIdAssociationByPort), so the real system pointer moves, with the system pointer speed. Falls back to powering the panel off if /dev/uhid is unavailable. While it is shown, the monitor's IME policy (DisplayContent.getImePolicy() → FALLBACK_DISPLAY) and the input-method service's display choice (computeImeDisplayIdForTarget) send the on-screen keyboard to the phone, in memory only and only when no physical keyboard is connected (otherwise every hardware key would go through an IME hidden behind the black screen); the overlay finds the visible TYPE_INPUT_METHOD window among the phone's windows (forAllWindows), shrinks above it, and the driver reader ignores fingers that land on the keyboard
DockAccessibility	system_server	Enabled accessibility services always start at boot, so the dock would also show up on the phone	Enables the dock's accessibility service (found dynamically in the dock package, e.g. SmartDock DockService) 4 s after the desktop starts, once the monitor's density/resolution are applied (SmartDock's service crashes on a configuration change while it is starting, and hardware keys, which pass through it, stall meanwhile), disables it when the cable is unplugged, and after boot if no monitor is attached. Also re-enables it if HyperOS turned it off
DesktopSession	system_server	The monitor keeps its default density (tiny UI on a 4K screen), can run at the wrong resolution/refresh, and the screen timeout can turn it off while you read	On connect, applies the monitor density (setForcedDisplayDensityForUser, like wm density), logical resolution (setForcedDisplaySize, like wm size) and, best-effort, refresh rate (Display.setUserPreferredDisplayMode, only choosing a mode the monitor actually reports — never a made-up one, so it can't blank the screen) chosen in the settings, each only if it differs from the current value; and, if enabled, holds a screen wake lock while the desktop is active. Changing any of them in the settings app triggers a signature-protected broadcast so system_server applies it at once
AltTabHooks	system_server	Alt+Tab is handled by the HyperOS launcher, which lives only on the phone: on the monitor it does nothing	Intercepts Alt+Tab at InputManagerService.interceptKeyBeforeQueueing only while a desktop display is active and has focus. While you hold Alt, a Windows-style preview bar of the open apps is drawn on the monitor (SwitcherOverlay, added from system_server); Tab moves the highlight, Alt+Shift+Tab the other way, and the app is switched when you release Alt. The bar can be turned off, then each Tab switches instantly. If the bar can't be drawn the module falls back to instant switching. On the phone, Alt+Tab is untouched
DesktopShortcuts	system_server	HyperOS screenshots only capture the phone display; no way to move apps between displays from the keyboard	More keyboard shortcuts at the same input hook as Alt+Tab, only while a desktop display is active (see Keyboard shortcuts). Monitor screenshots use DisplayManagerInternal.systemScreenshot(displayId) and are handed over a pipe to the module app (ShotProvider, protected by INTERACT_ACROSS_USERS_FULL), which saves them through MediaStore to Pictures/Screenshots (MediaProvider refuses to open files for writing to system_server). When a Win combination is consumed, the Win key-up is consumed too, so the system/dock does not treat it as "Win pressed alone"
SettingsHooks	Settings	The hidden AOSP External displays page crashes in DisplayTopologyPreferenceController (lateinit paneContent never set by the miuix adapter)	Marks that controller unavailable so the page renders

Settings are written by the module app (SettingsActivity) and read by the hooks through LSPosed's new XSharedPreferences (xposedsharedprefs), at the moment they are used, so changes need no reboot.

Logs go to logcat with the tag HyperDesktop (adb logcat -s HyperDesktop) and to LSPosed's log. At boot each process prints one summary line:

[diag] system_server v1.5.0: gate OK, desktop-flags OK, mirror-guard OK, mirror-policy OK, keys OK | settings: saved

MISSING there means a hook did not attach (usually because a firmware update renamed something) — please include that line in bug reports.

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Requirements

• Xiaomi phone with DisplayPort Alt Mode over USB-C (Xiaomi 15 has it; most Redmi/POCO do not).
• HyperOS 4 / Android 17 (the Android 17 connected-display code must be present; HyperOS 3 / Android 16 was not tested).
• Root (KernelSU/Magisk) with Zygisk and LSPosed.

Install

1. Grab the APK from Releases (or from the releases/ folder) and install it.
2. LSPosed → Modules → enable HyperDesktop Unlock.
3. Scope: System Framework, System UI, Settings.
4. Reboot.
5. Optional: open HyperDesktop Unlock from the app drawer (or the module's settings in LSPosed) to change the settings.

Use

1. Connect the monitor. The dialog now shows Computer above Mirroring.
2. Tap Computer (tick Don't ask again to make it automatic).
3. The monitor becomes a second display with its own status bar and cursor. If SmartDock (or the dock set in the settings) is installed, the module starts it on the monitor automatically. Otherwise launch apps from a shell:

   am start --display 2 -n com.android.settings/.Settings
   

   (dumpsys display | grep "Display [0-9]*:" lists display ids.)
4. The phone's own screen turns off automatically a couple of seconds later; the phone stays awake. Need the phone screen? Press power twice (lock + wake), or Win+P: it comes back and stays on until the next connection. It also comes back by itself for an incoming call. With Use the phone as a touchpad on, the screen stays black instead and works as a touchpad (see below).
5. Everything too small or too big on the monitor? Set Monitor density in the settings (4K monitors usually look right between 240 and 360 dpi); it applies immediately.
6. Back on the monitor: mouse side button, Esc on a keyboard, the launcher's Back button, or input -d 2 keyevent KEYCODE_BACK.

Settings

Setting	Default
Start the dock on the monitor	on	Launches the dock's desktop on the monitor when you choose Computer
Dock app (package name)	cu.axel.smartdock	e.g. com.farmerbb.taskbar for Taskbar
Also open on the monitor	none	Extra apps (package names) launched on the monitor after the dock, on connect
Manage the dock's accessibility service	on	On in desktop mode, off when unplugged and after boot
Turn off the phone screen in desktop mode	on	Power twice or Win+P brings it back
Use the phone as a touchpad	off	The phone screen stays black instead of off and works as a touchpad for the monitor
Touchpad sensitivity	6 of 20	Slider; higher = the pointer travels further. The system pointer speed applies on top
Keyboard on the phone	on	With the touchpad on and no physical keyboard, the on-screen keyboard opens on the phone, below the touchpad
Keep the monitor on	off	Ignores the screen timeout in desktop mode; the power button still works
Monitor density (dpi)	not set	100–800, or 0 for the monitor's default. Never touched until you set it; clear the field and Apply to stop changing it
Monitor resolution	not set	Picked from the sizes that fit the connected monitor, or Native. Lower = bigger UI, lighter on the GPU
Monitor refresh rate (Hz)	not set	Picked from the rates the monitor reports, or Native
Keep apps below the monitor's status bar (experimental)	off	For apps that draw under the monitor's status bar (e.g. a browser's tab strip). App windows on the monitor start below the bar; full-screen video is unaffected. Applies to apps opened afterwards
Desktop keyboard shortcuts	on	Alt+Tab and all the shortcuts below
Alt+Tab preview bar	on	Hold Alt for a Windows-style bar of the open apps; off = switch instantly on each Tab

If Show on-screen keyboard is on while you use a physical keyboard, the Keyboard section shows a warning with a Turn it off button (see If something goes wrong).

Touchpad (phone screen black, touch on)

Gesture	Action
One finger	Move the pointer on the monitor
Tap	Click
Tap, then touch and move	Drag
Two fingers	Scroll (natural direction, like on the phone)
Spread or pinch two fingers	Zoom (sent as Ctrl+wheel: works in apps that zoom with Ctrl+wheel, such as browsers)
Two-finger tap	Right click
Three fingers	Phone back to normal (so does Win+P)

Typing: tap a text field on the monitor; if no physical keyboard is connected, the on-screen keyboard opens on the phone and the touchpad shrinks above it.

Pointer speed: Touchpad sensitivity in the module's settings, on top of the system's pointer speed. The black screen shows a hint of the gestures for 15 seconds when it appears, then nothing.

Keyboard shortcuts (physical keyboard, desktop mode only)

Keys	Action
Alt+Tab	Switch apps on the monitor, with a preview bar while you hold Alt (can be turned off); keep Alt held and press Tab again to go further back, Alt+Shift+Tab for the other direction
Print Screen or Win+Shift+S	Screenshot of the monitor → Pictures/Screenshots (with focus on the phone: normal HyperOS screenshot)
Win+Shift+Arrow	Move the foreground app monitor → phone, or phone → monitor
Alt+F4	Close the foreground app on the monitor
Win+D	Show the dock's desktop on the monitor (starts it if it was closed)
Win+Backspace	Back, on the monitor
Win+1 … 9	Bring the Nth app open on the monitor to the front
Win+P	Turn the phone screen on/off

To go back to mirroring just pick Mirroring in the dialog (or clear the saved choice in Settings → External displays, reachable via am start -n com.android.settings/.SubSettings --es :settings:show_fragment com.android.settings.connecteddevice.display.ExternalDisplayPreferenceFragment).

Quick Settings tiles

Edit the tiles in the notification shade and add:

• Monitor: switches the connected monitor between Computer (desktop) and Mirroring without unplugging; going back to Computer starts the dock again.
• Touchpad: turns the phone into the touchpad right away (and back), and remembers the choice for the next connection.

Both need the phone unlocked.

If something goes wrong

• Open the module's settings → Diagnostics. The status line says whether the module is running in the system, whether a reboot is needed, and which parts did not attach. Create diagnostic report collects the phone model, Android and HyperOS version, the settings, the windows and insets on the monitor, and the module's recent log lines from the system and SystemUI; copy it, share it, or tap Report on GitHub and paste it.
• Or check the [diag] lines: adb logcat -s HyperDesktop | grep diag.
• Physical-keyboard text doesn't show up in apps on the monitor until you lock and unlock the phone (Delete and Backspace work, letters don't): turn off Show on-screen keyboard in the physical keyboard settings, or run adb shell settings put secure show_ime_with_hard_keyboard 0. With it on, the keyboard app keeps an on-screen keyboard session open for the app on the monitor and the letters get stuck in it. Apps with a plain text field (WhatsApp, for example) may work either way, which makes it look app-specific. Since 1.11.0 the module's settings warn you when it's on and can turn it off for you.
• An app on the monitor is covered by the status bar (its top row, such as a browser's tabs, sits under the clock and icons): since Android 15 apps draw edge to edge and must leave room for the bar themselves, and some don't on an external display. Turn on Keep apps below the monitor's status bar and reopen the app.
• After a reboot, SmartDock's settings open on the monitor with a permissions dialog, or its desktop shows a Let's start button: SmartDock's accessibility service crashed while starting (a SmartDock bug: a configuration change that arrives before onServiceConnected, reported upstream). Since 1.12.5 the module opens the dock's desktop only once the service is connected, which avoids it. If it still happens, unplug and replug the monitor.
• LSPosed disables a module automatically after repeated system crashes.
• Otherwise, with the phone plugged into a PC while booting:

  adb wait-for-device
  adb shell pm uninstall io.maurizio.hyperdesktop
  

  Uninstalling removes the module; nothing else is modified (no system partition changes). The persistent side effects are Settings.Secure.mirror_built_in_display = 0 (set it back to 1 to restore the stock behaviour without the module) and, only if you set them, the monitor's density, resolution and refresh rate, which Android remembers per monitor. The easiest way back: before uninstalling, with the monitor connected, set the density to 0 and resolution and refresh rate to Native in the module's settings. Or, after uninstalling, with adb (<id> is the monitor= line of the diagnostic report):

  adb shell wm density reset -d <id>
  adb shell wm size reset -d <id>
  adb shell cmd display clear-user-preferred-display-mode <id>
  

  Show on-screen keyboard (show_ime_with_hard_keyboard) is changed only when you tap Turn it off in the module's warning.
• Unplug the monitor before uninstalling. While a monitor is connected the module keeps the dock's accessibility service turned on, and turns it off when you unplug or at boot. Uninstalled with the monitor connected, nothing would turn it off again: in that case switch it off in Settings → Accessibility (the dock's service, e.g. SmartDock).

Build

Android Studio, or:

gradle assembleDebug        # debug-signed, for testing
gradle assembleRelease      # needs keystore.properties: without it the build stops

Create keystore.properties (git-ignored) next to settings.gradle:

storeFile=hyperdesktop-release.jks
storePassword=...
keyAlias=hyperdesktop
keyPassword=...

How it was found

Short version, in case you want to port it to another Xiaomi device:

1. aflags list showed every Android 17 desktop flag enabled but read-only.
2. The AOSP Settings page for external displays existed in Settings.apk (grep -ao 'connecteddevice/display/[A-Za-z$]*') and opened via am start.
3. Hooking DesktopModeStatus/DesktopModeFlags with discovery logging showed that the connect decision never consulted them.
4. The AOSP source of ExternalDisplayConnectionDialogDelegate proves the dialog always has two buttons → the Desktop button was hidden on purpose; hasOnClickListeners() was false → re-wire it.
5. A Settings.Secure.put* tracer with stack traces caught SecondaryDisplayPolicy re-enabling mirroring 3 ms after the desktop choice.
6. Blocking that write and neutralising the policy gave the separate display.

If your device differs, the [diag] line tells you which hook did not attach. The discovery logging used above (every call to the hooked classes with arguments and results, stack traces of settings writes) is in the project history up to tag v1.4.1.

Credits

Investigation and testing by Maurizio Laschi (@the-marox) on a Xiaomi 15; module written with the help of Claude (Anthropic). Built on LSPosed and the classic Xposed API.

Disclaimer

This modifies system behaviour at runtime on a rooted device. It works on the firmware it was tested on and may break on others. You are responsible for what you install. No warranty.

License

Copyright © 2026 Maurizio Laschi (@the-marox). Released under the MIT License — see LICENSE.

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🇮🇹 In breve

Modulo LSPosed per Xiaomi con HyperOS 4 (Android 17): ridà alla finestra "Connettiti a un display esterno" il pulsante Computer che Xiaomi nasconde, e neutralizza il meccanismo (SecondaryDisplayPolicy) che riporta il monitor in mirroring. Risultato: il monitor diventa un secondo display indipendente, con barra di stato, mouse e app a schermo intero. Per avere start menu, barra e cambio app sul monitor, abbina SmartDock: il modulo lo avvia da solo sul monitor, spegne lo schermo del telefono e aggiunge Alt+Tab, screenshot del monitor e altre scorciatoie da tastiera. Dalla 1.5.0 c'è un'app di impostazioni (in italiano) per scegliere il dock, lo spegnimento del telefono, la densità, risoluzione e frequenza del monitor, "tieni acceso" e le scorciatoie. Dalla 1.9 il telefono può fare da touchpad: lo schermo resta nero, un dito muove il puntatore, un tocco fa clic, due dita scorrono. Dalla 1.10 senza tastiera fisica la tastiera a schermo compare sul telefono, ci sono i riquadri rapidi Monitor (Computer ↔ Mirroring) e Touchpad, e nelle impostazioni c'è un report diagnostico da allegare alle segnalazioni. Le finestre ridimensionabili in stile AOSP non sono disponibili su questa build: Xiaomi non le espone e le finestre "mobili" di HyperOS hanno dimensione fissa. Dalla 1.11 allargando o stringendo due dita sul touchpad si fa lo zoom (Ctrl+rotella, nelle app che lo supportano, come i browser).

Se il testo dalla tastiera fisica non compare nelle app sul monitor finché non blocchi e sblocchi il telefono (Canc e Backspace funzionano, le lettere no), disattiva Mostra tastiera virtuale nelle impostazioni della tastiera fisica, oppure settings put secure show_ime_with_hard_keyboard 0. Dalla 1.11 le impostazioni del modulo te lo segnalano e possono disattivarlo con un tocco. Se un'app sul monitor finisce sotto la barra di stato (per esempio le schede di un browser), dalla 1.12 c'è l'opzione sperimentale App sotto la barra di stato del monitor. Dalla 1.12.5 il desktop di SmartDock si apre solo quando il suo servizio di accessibilità è già collegato: evita un crash di SmartDock al primo collegamento dopo un riavvio, che faceva comparire le sue impostazioni con il dialogo dei permessi. Prima di disinstallare il modulo, con il monitor collegato, rimetti la densità a 0 e risoluzione e frequenza su Nativa: Android le ricorda per ogni monitor (i comandi adb equivalenti sono nella sezione If something goes wrong). Poi scollega il monitor e solo dopo disinstalla: con il monitor collegato il modulo tiene acceso il servizio di accessibilità del dock, e dopo la disinstallazione nessuno lo spegnerebbe più (in quel caso: Impostazioni → Accessibilità).