isMissionReadyToExecute と MissionManager.isConnected をテストしたところ、いつ呼び出しても常に true が返されることがわかりました。したがって、SDK 内のバグである必要があると思います。
そして、この問題の回避策を見つけました。
ミッションを初期化します。
// Step 1: create mission
DJIWaypointMission waypointMission = new DJIWaypointMission();
waypointMission.maxFlightSpeed = 14;
waypointMission.autoFlightSpeed = 4;
List<DJIWaypoint> waypointsList = new LinkedList<>();
// Step 2: create waypoints and prepare coordinates
DJIWaypoint northPoint = new DJIWaypoint(mHomeLatitude + 10 * Utils.ONE_METER_OFFSET, mHomeLongitude, 10f);
DJIWaypoint eastPoint = new DJIWaypoint(mHomeLatitude, mHomeLongitude + 10 * Utils.calcLongitudeOffset(mHomeLatitude), 20f);
DJIWaypoint southPoint = new DJIWaypoint(mHomeLatitude - 10 * Utils.ONE_METER_OFFSET, mHomeLongitude, 30f);
DJIWaypoint westPoint = new DJIWaypoint(mHomeLatitude, mHomeLongitude - 10 * Utils.calcLongitudeOffset(mHomeLatitude), 40f);
//Step 3: add actions
northPoint.addAction(new DJIWaypoint.DJIWaypointAction(DJIWaypoint.DJIWaypointActionType.GimbalPitch, -60));
northPoint.addAction(new DJIWaypoint.DJIWaypointAction(DJIWaypoint.DJIWaypointActionType.StartTakePhoto, 0));
eastPoint.addAction(new DJIWaypoint.DJIWaypointAction(DJIWaypoint.DJIWaypointActionType.StartTakePhoto, 0));
southPoint.addAction(new DJIWaypoint.DJIWaypointAction(DJIWaypoint.DJIWaypointActionType.RotateAircraft, 60));
southPoint.addAction(new DJIWaypoint.DJIWaypointAction(DJIWaypoint.DJIWaypointActionType.StartRecord, 0));
westPoint.addAction(new DJIWaypoint.DJIWaypointAction(DJIWaypoint.DJIWaypointActionType.StopRecord, 0));
//Step 4: add waypoints into the mission
waypointsList.add(northPoint);
waypointsList.add(eastPoint);
waypointsList.add(southPoint);
waypointsList.add(westPoint);
waypointMission.addWaypoints(waypointsList);
mDJIMission = waypointMission;
ミッションを準備します。
mMissionManager.prepareMission(mDJIMission, new DJIMission.DJIMissionProgressHandler() {
@Override
public void onProgress(DJIMission.DJIProgressType type, float progress) {
setProgressBar((int)(progress * 100f));
}
}, new DJICompletionCallback() {
@Override
public void onResult(DJIError error) {
if (error == null) {
Utils.setResultToToast(mContext, "Success!");
} else {
Utils.setResultToToast(mContext, "Prepare: " + error.getDescription());
}
}
});