Overlapping collision area fails to fire touch event

Question

I have a "virtual" left button and right button for my game on my Android project using Godot 3.0. When the user presses/touches the left or right button, it will control the main character to move left or right. Here is the script for the right button.

func _on_RightButton_input_event(viewport, event, shape_idx):
    if (event is InputEventScreenTouch):
        if (event.pressed):
            emit_signal("right_btn_pressed", event)
        else:
            emit_signal("right_btn_released", event)

And this is the node structure of the right button:

RightButton (Area2D)
   +CollisionShape2D (a circle)
   +Sprite (a right arrow image)

I also have some enemy spawning randomly on the scene. They always move to the left and here is the script for the enemies

extends Node2D

enum MOVEMENT_TYPES{normal}
var movementType = MOVEMENT_TYPES.normal
export var motion = Vector2()
const UP = Vector2(0, -1)
var dyingBounce = true
var counter = 1

var enemyDie = false

func _physics_process(delta):
    if(enemyDie):
        if dyingBounce == true:
            motion.y = -100
            dyingBounce = false
        motion.y +=10
        if(movementType == MOVEMENT_TYPES.normal):
            motion = $Body.move_and_slide(motion, UP)
    else:
        var xf = Transform2D()
        xf[2]= motion * (delta * counter) 
        counter = counter - 2
        $Body.transform = xf


func hit_by_main_character():
    print("hit")
    $Body.get_node("CollisionShape2D").disabled = true
    enemyDie = true
    pass # replace with function body

func _on_VisibilityNotifier2D_screen_exited():
    queue_free()

And this is the node for the enemy:

Enemy
  + Body
    + VisibilityNotifier2D
    + ColorRect (just a rectangle as a place holder)
    + CollisionShape2D (also a rectangle)

Most of the time, the button works. However, when the enemy moves behind the right button, the right button will not emit the input_event signal. (I am connecting the input_event signal with _on_RightButton_input_event.) I am not sure if it is because of the overlapping CollisionShape2D, or some other issues. Please help. Any suggestions are welcome. Thank you!

Answer 1

Take me two whole days to figure it out. I am not sure why but the following config fixes the issues.

In the colorRect under Enemy, there is a "Mouse" section. Originally it was set to "stop". Change it to "Ignore" fixes the issue.