HyTalkPTT

HyTalkPTT is an Android application that enables a configurable physical PTT (Push-To-Talk) button to activate the HyTalk application. It works with Motorola LEX F10, UROVO DT30, Ulefone, and other devices whose PTT keycode you configure in the app.

Overview

The app intercepts PTT button presses and converts them into broadcast intents that HyTalk recognizes. It uses an Accessibility Service to capture global key events and sends android.intent.action.PTT_DOWN and android.intent.action.PTT_UP broadcasts. The PTT keycode is stored in app preferences (default 228 for Motorola LEX F10) and can be changed via Configure PTT Key in the app.

Requirements

• Devices: Motorola LEX F10 (default keycode 228), UROVO DT30, Ulefone (26WT, 20WT, 18T, etc.), or any device with a configurable PTT keycode
• Android: Android 5.1.1 (API 22)
• Target app: HyTalk (com.hytera.ocean)
• Android Studio: Latest with Android SDK

Features

• Configurable PTT keycode: Set via Configure PTT Key (press your hardware PTT → Save). Default 228 (Motorola LEX F10).
• Intercepts only the configured PTT key and converts it to broadcast intents for HyTalk
• Automatically launches or brings HyTalk to foreground when PTT is pressed
• Works when the app is in the background or was killed
• Minimal resource usage

Setup Instructions

Configure these three steps (in order):

1. Set PTT Key code

1. Open HyTalkPTT from the launcher.
2. Tap Configure PTT Key.
3. Press your device’s physical PTT button.
4. Tap Save settings.

The app stores the keycode (e.g. 228 for LEX F10, 520–522 for UROVO DT30, 381/301/131 for Ulefone). You can change it anytime by repeating these steps.

2. Programmable Keys

1. Go to Settings → Programmable Keys
2. Set PTT Key app (or equivalent) to HyTalkPTT

This lets the app receive PTT events when the device is locked or the app is in the background.

3. Accessibility Service

1. Go to Settings → Accessibility
2. Find HyTalkPTT and enable it

This allows global interception of the PTT key.

Building the Project

Prerequisites

• Android Studio (latest)
• Android SDK API 22
• JDK 8+

Build steps

1. Clone the repo:

   git clone https://github.com/chepil/HyTalkPTT.git
   cd HyTalkPTT

2. Open the project in Android Studio and sync Gradle.

3. Build and install:

   ./gradlew installDebug

   Or: Build → Make Project, then Run → Run 'app' with the device connected via USB (USB debugging enabled).

How It Works

1. Configured PTT keycode: The app uses a single keycode from SharedPreferences (default 228). You set it in Configure PTT Key.

2. Key event interception: PTTAccessibilityService receives global key events and reacts only when keyCode matches the stored value.

3. Broadcast intents:

   • ACTION_DOWN → android.intent.action.PTT_DOWN
   • ACTION_UP → android.intent.action.PTT_UP

4. HyTalk: Listens for these broadcasts and activates PTT.

5. Launch: If HyTalk is not running, the app launches it (or brings it to foreground) when PTT is pressed.

Technical Details

• Min/Target/Compile SDK: 22 (Android 5.1.1)
• Package: ru.chepil.hytalkptt
• Components:
  • MainActivity: App entry, setup UI, HyTalk launch.
  • PttKeySetupActivity: “Configure PTT Key” — detect hardware key, show keycode, save to preferences.
  • PttPreferences: Stores PTT keycode in SharedPreferences (default 228).
  • PTTAccessibilityService: Intercepts only the configured keycode and sends PTT broadcasts.

Permissions

• BIND_ACCESSIBILITY_SERVICE: For intercepting key events.
• SYSTEM_ALERT_WINDOW: Optional, not used currently.

Troubleshooting

PTT button has no effect

1. Set Configure PTT Key (press PTT, then Save).
2. Configure Programmable Keys (PTT Key app → HyTalkPTT).
3. Enable Accessibility for HyTalkPTT.
4. Check logcat:

   adb logcat | grep -i "HyTalkPTT\|PTTAccessibilityService"

HyTalk doesn’t launch

1. Install HyTalk (com.hytera.ocean).
2. Check logcat for launch errors.

Wrong key detected

• Open Configure PTT Key, press your PTT, confirm the shown keycode, then Save settings.
• On some devices, PTT may use different keycodes (e.g. 520, 521, 522 for UROVO DT30).

License

The MIT License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Author

Denis Chepil — den@chepil.ru

Tested with

• Motorola LEX F10 (default keycode 228)
• UROVO DT30 (keycodes 520, 521, 522)
• Ulefone Armor 26 WT, 20 WT, 18T (e.g. 381, 301, 131)