emulator-control

Emulator Control — drive + inspect KotlinExampleApp

The Android sibling of simulator-control. When testing KotlinExampleApp on an Android emulator, you can do everything the user could: tap by Compose testTag, type, swipe, screenshot, dump the view tree, unlock the device for auth-bound signing, fund a wallet, and run identity/DPNS/DashPay flows against live testnet. Use it alongside the human — confirm before spending funds or broadcasting.

Setup (once per session)

export ANDROID_HOME=/opt/homebrew/share/android-commandlinetools
export PATH=$ANDROID_HOME/platform-tools:$PATH
export JAVA_HOME=/opt/homebrew/opt/openjdk@17        # for any gradle work
adb devices                                          # find the running emulator
D=emulator-5554                                      # this session's serial
adb -s $D shell getprop ro.product.cpu.abi           # MUST be arm64-v8a on Apple Silicon
PKG=org.dashfoundation.example                       # KotlinExampleApp
adb -s $D shell monkey -p $PKG -c android.intent.category.LAUNCHER 1   # launch

AVDs on this Mac: kotlin_sdk_ci (arm64-v8a — use this) and kotlin_sdk_ci_x86 (x86_64 — will NOT run the arm64-only native lib). API 35.

The killer feature: tap by Compose testTag

MainActivity sets Modifier.semantics { testTagsAsResourceId = true }, so every Compose testTag shows up as resource-id in a uiautomator dump. That makes the app fully scriptable by stable IDs — never hardcode pixel coords. The whole driver is this helper (write it to the scratchpad once per session):

# ui.sh — dump the tree, find a node by resource-id (testTag) or text, tap center.
D=emulator-5554; X=/tmp/ui.xml
dump(){ adb -s $D shell uiautomator dump /sdcard/ui.xml >/dev/null 2>&1; adb -s $D pull /sdcard/ui.xml $X >/dev/null 2>&1; }
center_of(){ python3 - "$X" "$1" <<'PY'
import sys,re,xml.etree.ElementTree as ET
root=ET.parse(sys.argv[1]).getroot()
for n in root.iter('node'):
    if n.get('resource-id','')==sys.argv[2]:
        m=re.findall(r'\[(\d+),(\d+)\]\[(\d+),(\d+)\]',n.get('bounds',''))
        if m: x1,y1,x2,y2=map(int,m[0]); print((x1+x2)//2,(y1+y2)//2); break
PY
}
tap_id(){ dump; read x y < <(center_of "$1"); [ -n "$x" ] && adb -s $D shell input tap $x $y || echo "NOT FOUND: $1"; }
shot(){ adb -s $D exec-out screencap -p > "/tmp/${1:-shot}.png"; }