Adding support for Pillow Image Object in toga

changes/2142.feature.rst

@@ -0,0 +1,45 @@
+Added Pillow support in toga
+============================
+toga.Image
+----------
+`toga.Image` can now take Pillow Image Object. simply set pil_image parameter to the Pillow Object
+code-block::python
+    from PIL import Image as PIL_Image
+    import toga
+    myimg = PIL_Image.open("path/to/image.png")
+    image = toga.Image(pil_image=myimg)
+
+Also to convert a `toga.Image` object as Pillow Object
+code-block::python
+    pil_image = image.as_format(PIL_Image.Image)
+    #or
+    pil_image = image.as_format(format=PIL_Image.Image)
+
+toga.ImageView
+--------------
+pass a Pillow Object in `toga.ImageView` and it will show the image
+code-block::python
+    from PIL import Image as PIL_Image
+    import toga
+    myimg = PIL_Image.open("path/to/image.png")
+    imageview = toga.ImageView(myimg)
+
+Aslo to extract image as Pillow Object from the `imageview`
+code-block::python
+    pil_img = imageview.as_image(PIL_Image.Image)
+    #or
+    pil_img = imageview.as_image(format=PIL_Image.Image)
+
+toga.Canvas
+-----------
+`Canvas.as_image` now can return Pillow object if PIL.Image.Image set in the format parameter
+code-block::python
+    from PIL import Image as PIL_Image
+    pil_img = canvas.as_image(PIL_Image.Image)
+    #or
+    pil_img = canvas.as_image(format=PIL_Image.Image)
+
+When conversion format is `None`
+------------------------------
+Also when `format` is `None` in `Image.as_format` or `ImageView.as_image` or `Canvas.as_image`
+it will return a `toga.Image` object by default

core/tests/test_images.py

@@ -120,3 +120,23 @@ def test_image_save():
 
     image.save(save_path)
     assert_action_performed_with(image, "save", path=save_path)
+
+def test_pil_support():
+    from PIL import Image as PIL_Image
+
+    pil_img = PIL_Image.open("resources/toga.png")
+    toga_img = toga.Image("resources/toga.png")
+    toga_img_from_pil_img = toga.Image(pil_image = pil_img)
+
+    assert toga_img.width == toga_img_from_pil_img.width, "PIL support is faulty"
+    assert toga_img.height == toga_img_from_pil_img.height, "PIL support is faulty"
+
+    pil_img2 = toga_img_from_pil_img.as_format(PIL_Image.Image)
+
+    assert type(pil_img2) == type(pil_img), "Image.as_format(PIL_Image.Image) is faulty"
+    assert pil_img2.size == pil_img.size, "Image.as_format(PIL_Image.Image) is faulty"
+
+def test_as_format_none():
+    img = toga.Image("resources/toga.png")
+    img2 = img.as_format()
+    assert img == img2, "Image.as_format should return self when nothing is provided as arg, but failed"

core/tests/widgets/canvas/test_canvas.py

@@ -159,6 +159,11 @@ def test_as_image(widget):
     assert image is not None
     assert_action_performed(widget, "get image data")
 
+    from PIL import Image as PIL_Image
+    image = widget.as_image(format=PIL_Image.Image)
+    assert type(image) == PIL_Image.Image
+    assert_action_performed(widget, "get image data as Pillow Image Object")
+
 
 def test_deprecated_drawing_operations(widget):
     """Deprecated simple drawing operations raise a warning"""

core/tests/widgets/test_imageview.py

@@ -176,3 +176,21 @@ def test_rehint_empty_image(params):
     assert width == 0
     assert height == 0
     assert aspect_ratio is None
+
+def test_pil_support():
+    from PIL import Image as PIL_Image
+    pil_img = PIL_Image.open("resources/toga.png")
+    toga_img = PIL_Image.open("resources/toga.png")
+
+    imageview = toga.ImageView(pil_img)
+    assert type(imageview.image) == toga.Image, "Internal conversion from PIL_Image.Image to toga.Image is faulty"
+    assert (imageview.image.width, imageview.image.height) == (toga_img.width,toga_img.height) == pil_img.size, "PIL support for imageview is faulty"
+
+    pil_img2 = imageview.as_image(PIL_Image.Image)
+    assert pil_img2.size == pil_img2.size, "ImageView.as_image(PIL_Image.Image) is faulty"
+
+def test_as_image_format_is_none():
+    img = toga.Image("resources/toga.png")
+    imageview = toga.ImageView(image=img)
+    img2 = imageview.as_image()
+    assert (img2.width, img2.height) == (img.width, img.height), "ImageView.as_image should return toga.Image when nothing is provided as parameter, but failed"