[widget audit] toga.Label

android/src/toga_android/libs/android/graphics.py

@@ -13,3 +13,5 @@
 PorterDuffColorFilter = JavaClass("android/graphics/PorterDuffColorFilter")
 Rect = JavaClass("android/graphics/Rect")
 Typeface = JavaClass("android/graphics/Typeface")
+
+LineBreaker = JavaClass("android/graphics/text/LineBreaker")

android/src/toga_android/libs/android/os.py

@@ -0,0 +1,3 @@
+from rubicon.java import JavaClass
+
+Build = JavaClass("android/os/Build")

android/src/toga_android/widgets/label.py

@@ -1,7 +1,10 @@
 from travertino.size import at_least
 
+from toga.constants import JUSTIFY
 from toga_android.colors import native_color
 
+from ..libs.android.graphics import LineBreaker
+from ..libs.android.os import Build
 from ..libs.android.view import Gravity, View__MeasureSpec
 from ..libs.android.widget import TextView
 from .base import Widget, align
@@ -28,6 +31,9 @@ def create(self):
         self.native = TextView(self._native_activity)
         self.cache_textview_defaults()
 
+    def get_text(self):
+        return self.native.getText()
+
     def set_text(self, value):
         self.native.setText(value)
 
@@ -54,12 +60,15 @@ def rehint(self):
         self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
 
     def set_alignment(self, value):
-        # Refuse to set alignment if create() has not been called.
-        if self.native is None:
-            return
         # Refuse to set alignment if widget has no container.
         # On Android, calling setGravity() when the widget has no LayoutParams
         # results in a NullPointerException.
         if not self.native.getLayoutParams():
             return
+
+        # Justified text wasn't added until Android O (SDK 26)
+        if value == JUSTIFY and Build.VERSION.SDK_INT >= Build.VERSION_CODES.O:
+            self.native.setJustificationMode(LineBreaker.JUSTIFICATION_MODE_INTER_WORD)
+        else:
+            self.native.setJustificationMode(LineBreaker.JUSTIFICATION_MODE_NONE)
         self.native.setGravity(Gravity.CENTER_VERTICAL | align(value))

android/tests_backend/widgets/base.py

@@ -1,7 +1,6 @@
 import asyncio
 
 from java import dynamic_proxy
-from pytest import skip
 
 from android.view import ViewTreeObserver
 from toga.fonts import SYSTEM
@@ -48,8 +47,8 @@ def assert_container(self, container):
         else:
             raise AssertionError(f"cannot find {self.native} in {container_native}")
 
-    def assert_alignment_equivalent(self, actual, expected):
-        assert actual == expected
+    def assert_alignment(self, expected):
+        assert self.alignment == expected
 
     def assert_font_family(self, expected):
         actual = self.font.family
@@ -71,18 +70,6 @@ async def redraw(self):
     def enabled(self):
         return self.native.isEnabled()
 
-    @property
-    def background_color(self):
-        skip("not implemented: background_color")
-
-    @property
-    def color(self):
-        skip("not implemented: color")
-
-    @property
-    def hidden(self):
-        skip("not implemented: hidden")
-
     @property
     def width(self):
         # Return the value in DP

android/tests_backend/widgets/label.py

@@ -1,8 +1,7 @@
 from java import jclass
-from pytest import skip
 
 from .base import SimpleProbe
-from .properties import toga_color, toga_font
+from .properties import toga_alignment, toga_color, toga_font
 
 
 class LabelProbe(SimpleProbe):
@@ -30,4 +29,6 @@ def font(self):
 
     @property
     def alignment(self):
-        skip("Alignment probe not implemented")
+        return toga_alignment(
+            self.native.getGravity(), self.native.getJustificationMode()
+        )

android/tests_backend/widgets/properties.py

@@ -2,8 +2,11 @@
 from travertino.fonts import Font
 
 from android.graphics import Color, Typeface
+from android.graphics.text import LineBreaker
 from android.util import TypedValue
+from android.view import Gravity
 from toga.colors import TRANSPARENT, rgba
+from toga.constants import CENTER, JUSTIFY, LEFT, RIGHT
 from toga.fonts import (
     BOLD,
     ITALIC,
@@ -62,3 +65,20 @@ def toga_font(typeface, size, resources):
         variant=NORMAL,
         weight=BOLD if typeface.isBold() else NORMAL,
     )
+
+
+def toga_alignment(gravity, justification_mode):
+    horizontal_gravity = gravity & Gravity.HORIZONTAL_GRAVITY_MASK
+    if (
+        justification_mode == LineBreaker.JUSTIFICATION_MODE_INTER_WORD
+        and horizontal_gravity == Gravity.LEFT
+    ):
+        return JUSTIFY
+    elif justification_mode == LineBreaker.JUSTIFICATION_MODE_NONE:
+        return {
+            Gravity.LEFT: LEFT,
+            Gravity.RIGHT: RIGHT,
+            Gravity.CENTER_HORIZONTAL: CENTER,
+        }[horizontal_gravity]
+    else:
+        raise ValueError(f"unknown combination: {gravity=}, {justification_mode=}")

changes/1501.bugfix.rst

@@ -0,0 +1 @@
+iOS now supports newlines in Labels.

changes/1799.feature.rst

@@ -0,0 +1 @@
+The Label widget now has 100% test coverage, and complete API documentation.

cocoa/src/toga_cocoa/widgets/label.py

@@ -26,8 +26,11 @@ def set_color(self, value):
     def set_font(self, font):
         self.native.font = font._impl.native
 
+    def get_text(self):
+        return str(self.native.stringValue)
+
     def set_text(self, value):
-        self.native.stringValue = self.interface._text
+        self.native.stringValue = value
 
     def rehint(self):
         # Width & height of a label is known and fixed.

cocoa/tests_backend/widgets/base.py

@@ -17,8 +17,8 @@ def assert_container(self, container):
         else:
             raise ValueError(f"cannot find {self.native} in {container_native}")
 
-    def assert_alignment_equivalent(self, actual, expected):
-        assert actual == expected
+    def assert_alignment(self, expected):
+        assert self.alignment == expected
 
     def assert_font_family(self, expected):
         assert self.font.family == {

core/src/toga/widgets/label.py

@@ -1,5 +1,3 @@
-import warnings
-
 from .base import Widget
 
 
@@ -9,7 +7,6 @@ def __init__(
         text,
         id=None,
         style=None,
-        factory=None,  # DEPRECATED!
     ):
         """A text label.
 
@@ -19,35 +16,31 @@ def __init__(
         :param id: The ID for the widget.
         :param style: A style object. If no style is provided, a default style
             will be applied to the widget.
-        :param factory: *Deprecated*
         """
         super().__init__(id=id, style=style)
 
-        ######################################################################
-        # 2022-09: Backwards compatibility
-        ######################################################################
-        # factory no longer used
-        if factory:
-            warnings.warn("The factory argument is no longer used.", DeprecationWarning)
-        ######################################################################
-        # End backwards compatibility.
-        ######################################################################
-
         # Create a platform specific implementation of a Label
         self._impl = self.factory.Label(interface=self)
 
         self.text = text
 
     @property
     def text(self):
-        """The text displayed by the label."""
-        return self._text
+        """The text displayed by the label.
+
+        ``None``, and the Unicode codepoint U+200B (ZERO WIDTH SPACE), will be
+        interpreted and returned as an empty string. Any other object will be
+        converted to a string using ``str()``.
+
+        """
+        return self._impl.get_text()
 
     @text.setter
     def text(self, value):
-        if value is None:
-            self._text = ""
+        if value is None or value == "\u200B":
+            text = ""
         else:
-            self._text = str(value)
-        self._impl.set_text(value)
+            text = str(value)
+
+        self._impl.set_text(text)
         self.refresh()

core/tests/test_deprecated_factory.py

@@ -118,12 +118,6 @@ def test_image_view_created(self):
         self.assertEqual(widget._impl.interface, widget)
         self.assertNotEqual(widget.factory, self.factory)
 
-    def test_label_created(self):
-        with self.assertWarns(DeprecationWarning):
-            widget = toga.Label("Test", factory=self.factory)
-        self.assertEqual(widget._impl.interface, widget)
-        self.assertNotEqual(widget.factory, self.factory)
-
     def test_multiline_text_input_created(self):
         with self.assertWarns(DeprecationWarning):
             widget = toga.MultilineTextInput(factory=self.factory)

core/tests/widgets/test_label.py

@@ -1,27 +1,46 @@
+import pytest
+
 import toga
-from toga_dummy.utils import TestCase
+from toga_dummy.utils import (
+    EventLog,
+    assert_action_performed,
+    attribute_value,
+)
+
+
+@pytest.fixture
+def label():
+    return toga.Label("Test Label")
 
 
-class LabelTests(TestCase):
-    def setUp(self):
-        super().setUp()
+def test_label_created(label):
+    "A label can be created."
+    # Round trip the impl/interface
+    assert label._impl.interface == label
+    assert_action_performed(label, "create Label")
 
-        self.text = "test text"
 
-        self.label = toga.Label(self.text)
+@pytest.mark.parametrize(
+    "value, expected",
+    [
+        ("New Text", "New Text"),
+        (12345, "12345"),
+        (None, ""),
+        ("\u200B", ""),
+        ("Contains\nsome\nnewlines", "Contains\nsome\nnewlines"),
+    ],
+)
+def test_update_label_text(label, value, expected):
+    assert label.text == "Test Label"
 
-    def test_widget_created(self):
-        self.assertEqual(self.label._impl.interface, self.label)
-        self.assertActionPerformed(self.label, "create Label")
+    # Clear the event log
+    EventLog.reset()
 
-    def test_update_label_text(self):
-        new_text = "updated text"
-        self.label.text = new_text
-        self.assertEqual(self.label.text, new_text)
-        self.assertValueSet(self.label, "text", new_text)
-        self.assertActionPerformed(self.label, "refresh")
+    label.text = value
+    assert label.text == expected
 
-        self.label.text = None
-        self.assertEqual(self.label.text, "")
+    # test backend has the right value
+    assert attribute_value(label, "text") == expected
 
-        self.assertValueSet(self.label, "text", "")
+    # A rehint was performed
+    assert_action_performed(label, "refresh")

docs/reference/api/widgets/button.rst

@@ -27,7 +27,7 @@ A button has a text label. A handler can be associated with button press events.
         # handle event
         pass
 
-    button = toga.Button('Click me', on_press=my_callback)
+    button = toga.Button("Click me", on_press=my_callback)
 
 Notes
 -----

docs/reference/api/widgets/label.rst

@@ -20,7 +20,7 @@ Usage
 
     import toga
 
-    label = toga.Label('Hello world')
+    label = toga.Label("Hello world")
 
 Notes
 -----

docs/reference/data/widgets_by_platform.csv

@@ -9,7 +9,7 @@ DatePicker,General Widget,:class:`~toga.widgets.datepicker.DatePicker`,An input
 DetailedList,General Widget,:class:`~toga.widgets.detailedlist.DetailedList`,A list of complex content,|b|,|b|,,|b|,|b|,
 Divider,General Widget,:class:`~toga.widgets.divider.Divider`,A horizontal or vertical line,|b|,|b|,|b|,,,
 ImageView,General Widget,:class:`~toga.widgets.imageview.ImageView`,Image Viewer,|b|,|b|,|b|,|b|,|b|,
-Label,General Widget,:class:`~toga.widgets.label.Label`,Text label,|b|,|b|,|b|,|b|,|b|,|b|
+Label,General Widget,:class:`~toga.widgets.label.Label`,Text label,|y|,|y|,|y|,|y|,|y|,|b|
 MultilineTextInput,General Widget,:class:`~toga.widgets.multilinetextinput.MultilineTextInput`,Multi-line Text Input field,|b|,|b|,|b|,|b|,|b|,
 NumberInput,General Widget,:class:`~toga.widgets.numberinput.NumberInput`,Number Input field,|b|,|b|,|b|,|b|,|b|,
 PasswordInput,General Widget,:class:`~toga.widgets.passwordinput.PasswordInput`,A text input that hides it’s input,|b|,|b|,|b|,|b|,|b|,

dummy/src/toga_dummy/widgets/label.py

@@ -8,5 +8,8 @@ def create(self):
     def set_alignment(self, value):
         self._set_value("alignment", value)
 
+    def get_text(self):
+        return self._get_value("text")
+
     def set_text(self, value):
-        self._set_value("text", self.interface._text)
+        self._set_value("text", value)

gtk/src/toga_gtk/fonts.py

@@ -1,4 +1,11 @@
-from toga.constants import BOLD, ITALIC, OBLIQUE, SMALL_CAPS, SYSTEM
+from toga.constants import (
+    BOLD,
+    ITALIC,
+    OBLIQUE,
+    SMALL_CAPS,
+    SYSTEM,
+    SYSTEM_DEFAULT_FONT_SIZE,
+)
 
 from .libs import Pango
 
@@ -27,8 +34,9 @@ def __init__(self, interface):
 
             font.set_family(family)
 
-            # Set font size
-            font.set_size(self.interface.size * Pango.SCALE)
+            # If this is a non-default font size, set the font size
+            if self.interface.size != SYSTEM_DEFAULT_FONT_SIZE:
+                font.set_size(self.interface.size * Pango.SCALE)
 
             # Set font style
             if self.interface.style == ITALIC:

gtk/src/toga_gtk/widgets/button.py

@@ -13,7 +13,6 @@ def create(self):
         self.native.get_style_context().add_class("toga")
         self.native.interface = self.interface
 
-        self.native.connect("show", lambda event: self.refresh())
         self.native.connect("clicked", self.gtk_on_press)
 
     def get_text(self):