Add SystemUI demo mode README to tree.

# SystemUI Documentation

---

 * [Demo Mode](/packages/SystemUI/docs/demo_mode.md)

# Demo Mode for the Android System UI

*Demo mode for the status bar allows you to force the status bar into a fixed state, useful for taking screenshots with a consistent status bar state, or testing different status icon permutations. Demo mode is available in recent versions of Android.*

## Enabling demo mode

Demo mode is protected behind a system setting. To enable it for a device, run:

```

adb shell settings put global sysui_demo_allowed 1

```

## Protocol

The protocol is based on broadcast intents, and thus can be driven via the command line (```adb shell am broadcast```) or an app (```Context.sendBroadcast```).

### Broadcast action

```

com.android.systemui.demo

```

### Commands

Commands and subcommands (below) are sent as string extras in the broadcast

intent.

<br/>

Commands are sent as string extras with key ```command``` (required). Possible values are:

Command              | Subcommand         | Argument      | Description

---                  | ---                | ---           | ---

```enter```          |                    |               | Enters demo mode, bar state allowed to be modified (for convenience, any of the other non-exit commands will automatically flip demo mode on, no need to call this explicitly in practice)

```exit```           |                    |               | Exits demo mode, bars back to their system-driven state

```battery```        |                    |               | Control the battery display

                     | ```level```        |               | Sets the battery level (0 - 100)

                     | ```plugged```      |               | Sets charging state (```true```, ```false```)

```network```        |                    |               | Control the RSSI display

                     | ```airplane```     |               | ```show``` to show icon, any other value to hide

                     | ```fully```        |               | Sets MCS state to fully connected (```true```, ```false```)

                     | ```wifi```         |               | ```show``` to show icon, any other value to hide

                     |                    |```level```    | Sets wifi level (null or 0-4)

                     | ```mobile```       |               | ```show``` to show icon, any other value to hide

                     |                    |```datatype``` | Values: ```1x```, ```3g```, ```4g```, ```e```, ```g```, ```h```, ```lte```, ```roam```, any other value to hide

                     |                    |```level```    | Sets mobile signal strength level (null or 0-4)

```bars```           |                    |               | Control the visual style of the bars (opaque, translucent, etc)

                     | ```mode```         |               | Sets the bars visual style (opaque, translucent, semi-transparent)

```status```         |                    |               | Control the system status icons

                     | ```volume```       |               | Sets the icon in the volume slot (```silent```, ```vibrate```, any other value to hide)

                     | ```bluetooth```    |               | Sets the icon in the bluetooth slot (```connected```, ```disconnected```, any other value to hide)

                     | ```location```     |               | Sets the icon in the location slot (```show```, any other value to hide)

                     | ```alarm```        |               | Sets the icon in the alarm_clock slot (```show```, any other value to hide)

                     | ```sync```         |               | Sets the icon in the sync_active slot (```show```, any other value to hide)

                     | ```tty```          |               | Sets the icon in the tty slot (```show```, any other value to hide)

                     | ```eri```          |               | Sets the icon in the cdma_eri slot (```show```, any other value to hide)

                     | ```mute```         |               | Sets the icon in the mute slot (```show```, any other value to hide)

                     | ```speakerphone``` |               | Sets the icon in the speakerphone slot (```show```, any other value to hide)

```notifications```  |                    |               | Control the notification icons

                     | ```visible```      |               | ```false``` to hide the notification icons, any other value to show

```clock```          |                    |               | Control the clock display

                     | ```millis```       |               | Sets the time in millis

                     | ```hhmm```         |               | Sets the time in hh:mm

## Examples

Enter demo mode

```

adb shell am broadcast -a com.android.systemui.demo -e command enter

```

Exit demo mode

```

adb shell am broadcast -a com.android.systemui.demo -e command exit

```

Set the clock to 12:31

```

adb shell am broadcast -a com.android.systemui.demo -e command clock -e hhmm

1231

```

Set the wifi level to max

```

adb shell am broadcast -a com.android.systemui.demo -e command network -e wifi

show -e level 4

```

Show the silent volume icon

```

adb shell am broadcast -a com.android.systemui.demo -e command status -e volume

silent

```

Empty battery, and not charging (red exclamation point)

```

adb shell am broadcast -a com.android.systemui.demo -e command battery -e level

0 -e plugged false

```

Hide the notification icons

```

adb shell am broadcast -a com.android.systemui.demo -e command notifications -e

visible false

```

Exit demo mode

```

adb shell am broadcast -a com.android.systemui.demo -e command exit

```

## Example demo controller app in AOSP

```

frameworks/base/tests/SystemUIDemoModeController

```

## Example script (for screenshotting purposes)

```bash

#!/bin/sh

CMD=$1

if [[ $ADB == "" ]]; then

  ADB=adb

fi

if [[ $CMD != "on" && $CMD != "off" ]]; then

  echo "Usage: $0 [on|off] [hhmm]" >&2

  exit

fi

if [[ "$2" != "" ]]; then

  HHMM="$2"

fi

$ADB root || exit

$ADB wait-for-devices

$ADB shell settings put global sysui_demo_allowed 1

if [ $CMD == "on" ]; then

  $ADB shell am broadcast -a com.android.systemui.demo -e command enter || exit

  if [[ "$HHMM" != "" ]]; then

    $ADB shell am broadcast -a com.android.systemui.demo -e command clock -e

hhmm ${HHMM}

  fi

  $ADB shell am broadcast -a com.android.systemui.demo -e command battery -e

plugged false

  $ADB shell am broadcast -a com.android.systemui.demo -e command battery -e

level 100

  $ADB shell am broadcast -a com.android.systemui.demo -e command network -e

wifi show -e level 4

  $ADB shell am broadcast -a com.android.systemui.demo -e command network -e

mobile show -e datatype none -e level 4

  $ADB shell am broadcast -a com.android.systemui.demo -e command notifications

-e visible false

elif [ $CMD == "off" ]; then

  $ADB shell am broadcast -a com.android.systemui.demo -e command exit

fi

```