Merge pull request #2186 from mhsmith/scale-min-size

Correct scaling of MIN_WIDTH and MIN_HEIGHT on Android and WinForms

android/src/toga_android/widgets/base.py

@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from decimal import ROUND_HALF_EVEN, ROUND_UP, Decimal
+from decimal import ROUND_HALF_EVEN, Decimal
 
 from android.graphics import PorterDuff, PorterDuffColorFilter, Rect
 from android.graphics.drawable import ColorDrawable, InsetDrawable
@@ -182,18 +182,13 @@ def remove_child(self, child):
     # TODO: consider calling requestLayout or forceLayout here
     # (https://github.com/beeware/toga/issues/1289#issuecomment-1453096034)
     def refresh(self):
-        intrinsic = self.interface.intrinsic
-        intrinsic.width = intrinsic.height = None
+        # Default values; may be overwritten by rehint().
+        self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
+        self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)
         self.rehint()
-        assert intrinsic.width is not None, self
-        assert intrinsic.height is not None, self
 
-        intrinsic.width = self.scale_out(intrinsic.width, ROUND_UP)
-        intrinsic.height = self.scale_out(intrinsic.height, ROUND_UP)
-
-    @abstractmethod
     def rehint(self):
-        ...
+        pass
 
 
 def align(value):

android/src/toga_android/widgets/box.py

@@ -1,5 +1,4 @@
 from android.widget import RelativeLayout
-from travertino.size import at_least
 
 from .base import Widget
 
@@ -10,7 +9,3 @@ def create(self):
 
     def set_background_color(self, value):
         self.set_background_simple(value)
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(0)
-        self.interface.intrinsic.height = at_least(0)

android/src/toga_android/widgets/button.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android.view import View
 from android.widget import Button as A_Button
 from java import dynamic_proxy
@@ -40,5 +42,9 @@ def rehint(self):
             View.MeasureSpec.UNSPECIFIED,
             View.MeasureSpec.UNSPECIFIED,
         )
-        self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.getMeasuredWidth()), ROUND_UP
+        )
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/canvas.py

@@ -12,7 +12,6 @@
 from java import dynamic_proxy, jint
 from java.io import ByteArrayOutputStream
 from org.beeware.android import DrawHandlerView, IDrawHandler
-from travertino.size import at_least
 
 from toga.widgets.canvas import Baseline, FillRule
 
@@ -265,7 +264,3 @@ def get_image_data(self):
 
     def set_background_color(self, value):
         self.set_background_simple(value)
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(0)
-        self.interface.intrinsic.height = at_least(0)

android/src/toga_android/widgets/detailedlist.py

@@ -8,7 +8,6 @@
 from android.widget import ImageView, LinearLayout, RelativeLayout, ScrollView, TextView
 from androidx.swiperefreshlayout.widget import SwipeRefreshLayout
 from java import dynamic_proxy
-from travertino.size import at_least
 
 from .base import Widget
 
@@ -243,7 +242,3 @@ def scroll_to_row(self, row):
             hit_rect,
             True,  # Immediate, not animated
         )
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
-        self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)

android/src/toga_android/widgets/imageview.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android.widget import ImageView as A_ImageView
 
 from toga.widgets.imageview import rehint_imageview
@@ -21,7 +23,7 @@ def set_image(self, image):
 
     def rehint(self):
         # User specified sizes are in "pixels", which is DP;
-        # we need to convert all sizes into SP.
+        # we need to convert all sizes into physical pixels.
         dpi = self.native.getContext().getResources().getDisplayMetrics().densityDpi
         # Toga needs to know how the current DPI compares to the platform default,
         # which is 160: https://developer.android.com/training/multiscreen/screendensities
@@ -30,8 +32,8 @@ def rehint(self):
         width, height, aspect_ratio = rehint_imageview(
             image=self.interface.image, style=self.interface.style, scale=scale
         )
-        self.interface.intrinsic.width = width
-        self.interface.intrinsic.height = height
+        self.interface.intrinsic.width = self.scale_out(width, ROUND_UP)
+        self.interface.intrinsic.height = self.scale_out(height, ROUND_UP)
         if aspect_ratio is not None:
             self.native.setScaleType(A_ImageView.ScaleType.FIT_CENTER)
         else:

android/src/toga_android/widgets/internal/pickers.py

@@ -1,4 +1,5 @@
 from abc import ABC, abstractmethod
+from decimal import ROUND_UP
 
 from android.view import View
 from android.widget import EditText
@@ -42,4 +43,6 @@ def create(self):
     def rehint(self):
         self.interface.intrinsic.width = at_least(300)
         self.native.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/label.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android.os import Build
 from android.text import Layout
 from android.util import TypedValue
@@ -68,13 +70,15 @@ def rehint(self):
         # This is the height with word-wrapping disabled.
         self.native.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
         min_height = self.native.getMeasuredHeight()
-        self.interface.intrinsic.height = min_height
+        self.interface.intrinsic.height = self.scale_out(min_height, ROUND_UP)
         # Ask it how wide it would be if it had to be the minimum height.
         self.native.measure(
             View.MeasureSpec.UNSPECIFIED,
             View.MeasureSpec.makeMeasureSpec(min_height, View.MeasureSpec.AT_MOST),
         )
-        self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.getMeasuredWidth()), ROUND_UP
+        )
 
     def set_alignment(self, value):
         self.set_textview_alignment(value, Gravity.TOP)

android/src/toga_android/widgets/multilinetextinput.py

@@ -26,6 +26,7 @@ def _on_lose_focus(self):
     def set_alignment(self, value):
         self.set_textview_alignment(value, Gravity.TOP)
 
+    # This method is necessary to override the TextInput base class.
     def rehint(self):
         self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
         self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)

android/src/toga_android/widgets/progressbar.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android import R
 from android.view import View
 from android.widget import ProgressBar as A_ProgressBar
@@ -92,5 +94,9 @@ def rehint(self):
             View.MeasureSpec.UNSPECIFIED,
             View.MeasureSpec.UNSPECIFIED,
         )
-        self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.getMeasuredWidth()), ROUND_UP
+        )
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/scrollcontainer.py

@@ -3,7 +3,6 @@
 from android.view import Gravity, View
 from android.widget import HorizontalScrollView, LinearLayout, ScrollView
 from java import dynamic_proxy
-from travertino.size import at_least
 
 from ..container import Container
 from .base import Widget
@@ -103,7 +102,3 @@ def set_position(self, horizontal_position, vertical_position):
 
     def set_background_color(self, value):
         self.set_background_simple(value)
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(0)
-        self.interface.intrinsic.height = at_least(0)

android/src/toga_android/widgets/selection.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android import R
 from android.view import View
 from android.widget import AdapterView, ArrayAdapter, Spinner
@@ -84,5 +86,9 @@ def clear(self):
 
     def rehint(self):
         self.native.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
-        self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.getMeasuredWidth()), ROUND_UP
+        )
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/slider.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android import R
 from android.view import View
 from android.widget import SeekBar
@@ -67,5 +69,9 @@ def _load_tick_drawable(self):
 
     def rehint(self):
         self.native.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
-        self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.getMeasuredWidth()), ROUND_UP
+        )
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/switch.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 from android.view import View
 from android.widget import CompoundButton, Switch as A_Switch
 from java import dynamic_proxy
@@ -43,5 +45,9 @@ def set_value(self, value):
 
     def rehint(self):
         self.native.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
-        self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.getMeasuredWidth()), ROUND_UP
+        )
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/table.py

@@ -5,7 +5,6 @@
 from android.view import Gravity, View
 from android.widget import LinearLayout, ScrollView, TableLayout, TableRow, TextView
 from java import dynamic_proxy
-from travertino.size import at_least
 
 import toga
 
@@ -221,7 +220,3 @@ def set_background_color(self, value):
     def set_font(self, font):
         self._font_impl = font._impl
         self.change_source(self.interface.data)
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
-        self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)

android/src/toga_android/widgets/textinput.py

@@ -1,8 +1,9 @@
+from decimal import ROUND_UP
+
 from android.text import InputType, TextWatcher
 from android.view import Gravity, View
 from android.widget import EditText
 from java import dynamic_proxy
-from travertino.size import at_least
 
 from toga_android.keys import toga_key
 
@@ -123,6 +124,7 @@ def _on_lose_focus(self):
         self.interface.on_lose_focus()
 
     def rehint(self):
-        self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
         self.native.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
-        self.interface.intrinsic.height = self.native.getMeasuredHeight()
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.getMeasuredHeight(), ROUND_UP
+        )

android/src/toga_android/widgets/webview.py

@@ -2,7 +2,6 @@
 
 from android.webkit import ValueCallback, WebView as A_WebView, WebViewClient
 from java import dynamic_proxy
-from travertino.size import at_least
 
 from toga.widgets.webview import JavaScriptResult
 
@@ -81,7 +80,3 @@ def evaluate_javascript(self, javascript, on_result=None):
             javascript, ReceiveString(result.future, on_result)
         )
         return result
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
-        self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)

changes/2186.misc.rst

@@ -0,0 +1 @@
+Correct scaling of MIN_WIDTH and MIN_HEIGHT on Android and WinForms

core/src/toga/widgets/box.py

@@ -4,6 +4,9 @@
 
 
 class Box(Widget):
+    _MIN_WIDTH = 0
+    _MIN_HEIGHT = 0
+
     def __init__(
         self,
         id: str | None = None,

core/src/toga/widgets/canvas.py

@@ -1181,6 +1181,9 @@ def __call__(self, widget: Canvas, width: int, height: int, **kwargs):
 
 
 class Canvas(Widget):
+    _MIN_WIDTH = 0
+    _MIN_HEIGHT = 0
+
     def __init__(
         self,
         id=None,

core/src/toga/widgets/scrollcontainer.py

@@ -6,6 +6,9 @@
 
 
 class ScrollContainer(Widget):
+    _MIN_WIDTH = 0
+    _MIN_HEIGHT = 0
+
     def __init__(
         self,
         id=None,

winforms/src/toga_winforms/widgets/base.py

@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from decimal import ROUND_HALF_EVEN, ROUND_UP, Decimal
+from decimal import ROUND_HALF_EVEN, Decimal
 
 from System.Drawing import (
     Color,
@@ -144,15 +144,10 @@ def remove_child(self, child):
         child.container = None
 
     def refresh(self):
-        intrinsic = self.interface.intrinsic
-        intrinsic.width = intrinsic.height = None
+        # Default values; may be overwritten by rehint().
+        self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
+        self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)
         self.rehint()
-        assert intrinsic.width is not None
-        assert intrinsic.height is not None
 
-        intrinsic.width = self.scale_out(intrinsic.width, ROUND_UP)
-        intrinsic.height = self.scale_out(intrinsic.height, ROUND_UP)
-
-    @abstractmethod
     def rehint(self):
-        ...
+        pass

winforms/src/toga_winforms/widgets/box.py

@@ -1,13 +1,8 @@
 import System.Windows.Forms as WinForms
-from travertino.size import at_least
 
 from .base import Widget
 
 
 class Box(Widget):
     def create(self):
         self.native = WinForms.Panel()
-
-    def rehint(self):
-        self.interface.intrinsic.width = at_least(0)
-        self.interface.intrinsic.height = at_least(0)

winforms/src/toga_winforms/widgets/button.py

@@ -1,3 +1,5 @@
+from decimal import ROUND_UP
+
 import System.Windows.Forms as WinForms
 from travertino.size import at_least
 
@@ -31,7 +33,9 @@ def set_text(self, text):
         self.native.Text = text
 
     def rehint(self):
-        # self.native.Size = Size(0, 0)
-        # print("REHINT Button", self, self.native.PreferredSize)
-        self.interface.intrinsic.width = at_least(self.native.PreferredSize.Width)
-        self.interface.intrinsic.height = self.native.PreferredSize.Height
+        self.interface.intrinsic.width = self.scale_out(
+            at_least(self.native.PreferredSize.Width), ROUND_UP
+        )
+        self.interface.intrinsic.height = self.scale_out(
+            self.native.PreferredSize.Height, ROUND_UP
+        )