Master Python + ADB: Build Multi‑Device Automation Scripts for Android Apps

1. Introduction

Group control—controlling several Android devices from a single computer—is common in automation testing. This article shows how to write a Python‑ADB script to automate tasks across multiple devices.

2. Preparation

Install the Android development environment, ensure adb is added to the system PATH, and connect the devices via USB or a hub. Verify the connections with:

# Below shows three connected devices
xag:Test xingag$ adb devices
List of devices attached
822QEDTL225T7    device
ca2b3455        device
DE45d9323SE96   device

3. Practical Example

Using the Xianyu app as a case study, the automation consists of seven steps: obtain the package name and launch activity, list online devices, start the app on each device, perform UI actions defined in a YAML file, and finally stop the app.

Step 1 – Get package name and launch activity

# Get current running app package and initial Activity
adb shell dumpsys activity | grep -i run

Run the command on the device; the output displays the package and activity.

Step 2 – Get all online devices

# All device IDs
device_ids = []

def get_online_devices(self):
    """Retrieve all online devices"""
    global device_ids
    try:
        for line in exec_cmd("adb devices"):
            # Skip the first line and offline entries
            if "device" in line:
                device_ids.append(line.split("\t")[0])
        device_ids = device_ids[1:]
    except Exception as e:
        print(e)
    # Return connected devices and count
    return device_ids

Step 3 – Launch the target app on each device

def start_app(self):
    """Open the app on all devices"""
    for device in device_ids:
        os.popen("adb -s " + device + " shell am start -W {}/{}".format(self.packageName, self.home_activity))
    print('Waiting for loading...')
    sleep(10)

Step 4 – Save UI hierarchy locally

def save_ui_tree_to_local(dName):
    """Dump the current Activity UI tree and pull it locally"""
    exec_cmd("adb -s %s shell uiautomator dump /data/local/tmp/%s.xml" % (dName, dName))
    sleep(2)
    exec_cmd("adb -s %s pull /data/local/tmp/%s.xml ./../" % (dName, dName))

Step 5 – Parse UI XML to obtain element coordinates

def get_element_position(element_id, uidump_name):
    """Parse the UI XML, find the element by id, and return its center coordinates"""
    tree = ET.parse('./../%s.xml' % uidump_name)
    root = tree.getroot()
    result_element = None
    for node in root.findall('.//node'):
        if node.attrib['resource-id'] == element_id:
            result_element = node
            break
    if result_element is None:
        print('Element not found!')
        return None
    coord = re.compile(r"\d+").findall(result_element.attrib['bounds'])
    center = (int((int(coord[0]) + int(coord[2])) / 2), int((int(coord[1]) + int(coord[3])) / 2))
    return center

Step 6 – Execute steps from a YAML file

# steps_adb.yaml

# Package and Activity
package_name:  com.taobao.idlefish
home_activity:  com.taobao.fleamarket.home.activity.InitActivity

# Execution steps
steps:
  - save_ui_tree_to_local:
      method: save_ui_tree_to_local
      args:
  - find_element_and_click:
      id: com.taobao.idlefish:id/tx_id
  - save_ui_tree_to_local:
      method: save_ui_tree_to_local
  - input_content:
      content: Python
  - find_element_and_click:
      id: com.taobao.idlefish:id/search_button

The script reads each step, iterates over all devices, and performs the corresponding action (save UI tree, locate element, click, input text, etc.).

# Execute steps
for step in self.steps:
    for device in device_ids:
        step_name = list(step)[0]
        if step_name == 'save_ui_tree_to_local':
            save_ui_tree_to_local(device)
        elif step_name == 'find_element_and_click':
            element_id = step[step_name]['id']
            pos = get_element_position(element_id, device)
            exec_cmd('adb -s %s shell input tap %s %s' % (device, pos[0], pos[1]))
        elif step_name == 'input_content':
            content = step[step_name]['content']
            exec_cmd('adb -s %s shell input text %s' % (device, content))
        else:
            print('Other operation')

Step 7 – Close the app on all devices

def stop_all(self):
    """Force‑stop the app on every device"""
    for device in device_ids:
        os.popen("adb -s " + device + " shell am force-stop %s" % self.packageName)

4. Conclusion

This article presents the simplest Python‑based group‑control implementation for Android apps; more advanced techniques will be explored in future posts.