Modify container handling for GTK

android/src/toga_android/widgets/base.py

@@ -1,5 +1,6 @@
-from toga.constants import CENTER, JUSTIFY, LEFT, RIGHT
+from toga.constants import CENTER, JUSTIFY, LEFT, RIGHT, TRANSPARENT
 
+from ..colors import native_color
 from ..libs.activity import MainActivity
 from ..libs.android.view import Gravity, View
 
@@ -111,6 +112,14 @@ def set_background_color(self, color):
         # By default, background color can't be changed.
         pass
 
+    # Although setBackgroundColor is defined in the View base class, we can't use it as
+    # a default implementation because it often overwrites other aspects of the widget's
+    # appearance.
+    def set_background_color_simple(self, value):
+        self.native.setBackgroundColor(
+            native_color(TRANSPARENT if (value is None) else value)
+        )
+
     def set_alignment(self, alignment):
         pass  # If appropriate, a widget subclass will implement this.
 
@@ -132,6 +141,9 @@ def insert_child(self, index, child):
     def remove_child(self, child):
         child.container = None
 
+    def refresh(self):
+        self.rehint()
+
     def rehint(self):
         pass
 

android/src/toga_android/widgets/box.py

@@ -1,6 +1,5 @@
-from travertino.constants import TRANSPARENT
+from travertino.size import at_least
 
-from ..colors import native_color
 from ..libs.activity import MainActivity
 from ..libs.android.widget import RelativeLayout, RelativeLayout__LayoutParams
 from .base import Widget
@@ -24,6 +23,8 @@ def set_child_bounds(self, widget, x, y, width, height):
         self.native.updateViewLayout(widget.native, layout_params)
 
     def set_background_color(self, value):
-        self.native.setBackgroundColor(
-            native_color(TRANSPARENT if (value is None) else value)
-        )
+        self.set_background_color_simple(value)
+
+    def rehint(self):
+        self.interface.intrinsic.width = at_least(0)
+        self.interface.intrinsic.height = at_least(0)

android/src/toga_android/widgets/datepicker.py

@@ -74,6 +74,3 @@ def _create_dialog(self):
         self.set_min_date(self.interface._min_date)
         self.set_max_date(self.interface._max_date)
         self._dialog.show()
-
-    def rehint(self):
-        return super().rehint()

android/src/toga_android/widgets/label.py

@@ -20,6 +20,9 @@ def set_font(self, font):
             self.native.setTextSize(TypedValue.COMPLEX_UNIT_SP, font._impl.get_size())
             self.native.setTypeface(font._impl.get_typeface(), font._impl.get_style())
 
+    def set_background_color(self, value):
+        self.set_background_color_simple(value)
+
     def set_color(self, color):
         if color:
             self.native.setTextColor(native_color(color))

android/src/toga_android/widgets/switch.py

@@ -32,7 +32,6 @@ def set_text(self, text):
         # is required to get the text to truly **use** one single line!
         self.native.setSingleLine(False)
         self.native.setText(str(self.interface.text))
-        self.rehint()
 
     def set_value(self, value):
         self.native.setChecked(bool(value))

android/src/toga_android/widgets/timepicker.py

@@ -62,6 +62,3 @@ def _create_dialog(self):
             True,
         )
         self._dialog.show()
-
-    def rehint(self):
-        return super().rehint()

changes/1205.bugfix.rst

@@ -0,0 +1 @@
+Issues with reducing the size of windows on GTK have been resolved.

changes/1794.bugfix.rst

@@ -0,0 +1 @@
+The handling of GTK layouts has been modified to reduce the frequency and increase the accuracy of layout results.

cocoa/src/toga_cocoa/widgets/activityindicator.py

@@ -16,7 +16,6 @@ def create(self):
 
         # Add the layout constraints
         self.add_constraints()
-        self.rehint()
 
     def start(self):
         self.native.startAnimation(self.native)

cocoa/src/toga_cocoa/widgets/base.py

@@ -114,5 +114,8 @@ def add_constraints(self):
         self.native.translatesAutoresizingMaskIntoConstraints = False
         self.constraints = Constraints(self)
 
+    def refresh(self):
+        self.rehint()
+
     def rehint(self):
         pass

cocoa/src/toga_cocoa/widgets/progressbar.py

@@ -13,7 +13,6 @@ def create(self):
 
         # Add the layout constraints
         self.add_constraints()
-        self.rehint()
 
     def set_value(self, value):
         self.native.doubleValue = self.interface.value

core/src/toga/style/applicator.py

@@ -28,7 +28,7 @@ def set_hidden(self, hidden):
 
     def set_font(self, font):
         self.widget._impl.set_font(font)
-        self.widget._impl.rehint()
+        self.widget.refresh()
 
     def set_color(self, color):
         self.widget._impl.set_color(color)

core/src/toga/widgets/base.py

@@ -274,6 +274,8 @@ def enabled(self, value):
         self._impl.set_enabled(value)
 
     def refresh(self):
+        self._impl.refresh()
+
         # Refresh the layout
         if self._root:
             self._root.refresh()

core/src/toga/widgets/button.py

@@ -98,7 +98,7 @@ def text(self, value):
         else:
             self._text = str(value)
         self._impl.set_text(value)
-        self._impl.rehint()
+        self.refresh()
 
     @property
     def on_press(self):

core/src/toga/widgets/divider.py

@@ -55,4 +55,4 @@ def direction(self):
     def direction(self, value):
         self._direction = value
         self._impl.set_direction(value)
-        self._impl.rehint()
+        self.refresh()

core/src/toga/widgets/imageview.py

@@ -51,7 +51,7 @@ def image(self, image):
 
         if self._image is not None:
             self._impl.set_image(image)
-            self._impl.rehint()
+            self.refresh()
 
         # @property
         # def alignment(self):

core/src/toga/widgets/label.py

@@ -50,4 +50,4 @@ def text(self, value):
         else:
             self._text = str(value)
         self._impl.set_text(value)
-        self._impl.rehint()
+        self.refresh()

core/src/toga/widgets/multilinetextinput.py

@@ -114,7 +114,7 @@ def value(self):
     def value(self, value):
         cleaned_value = "" if value is None else str(value)
         self._impl.set_value(cleaned_value)
-        self._impl.rehint()
+        self.refresh()
 
     def clear(self):
         """Clears the text from the widget."""

core/src/toga/widgets/scrollcontainer.py

@@ -81,7 +81,7 @@ def content(self, widget):
             self._content = widget
 
             self._impl.set_content(widget._impl)
-            self._impl.rehint()
+            self.refresh()
 
             widget.refresh()
 

core/src/toga/widgets/splitcontainer.py

@@ -134,4 +134,4 @@ def direction(self):
     def direction(self, value):
         self._direction = value
         self._impl.set_direction(value)
-        self._impl.rehint()
+        self.refresh()

core/src/toga/widgets/switch.py

@@ -140,7 +140,7 @@ def text(self, value):
         else:
             self._text = str(value)
         self._impl.set_text(value)
-        self._impl.rehint()
+        self.refresh()
 
     @property
     def on_change(self):

dummy/src/toga_dummy/widgets/base.py

@@ -71,5 +71,5 @@ def remove_child(self, child):
     def add_constraints(self):
         self._action("add constraints")
 
-    def rehint(self):
+    def refresh(self):
         self._action("rehint")

examples/resize/README.rst

@@ -0,0 +1,13 @@
+Resize Test
+===========
+
+Test app that demonstrates resizing of widgets and windows.
+
+Quickstart
+~~~~~~~~~~
+
+To run this example:
+
+    $ pip install toga
+    $ cd src
+    $ python -m resize

examples/resize/pyproject.toml

@@ -0,0 +1,55 @@
+[build-system]
+requires = ["briefcase"]
+
+[tool.briefcase]
+project_name = "Resize Test"
+bundle = "org.beeware"
+version = "0.0.1"
+url = "https://beeware.org"
+license = "BSD license"
+author = 'Tiberius Yak'
+author_email = "[email protected]"
+
+[tool.briefcase.app.resize]
+formal_name = "Resize Test"
+description = "A testing app"
+sources = ['src/resize']
+requires = [
+    '../../core',
+]
+
+
+[tool.briefcase.app.resize.macOS]
+requires = [
+    '../../cocoa',
+    'std-nslog>=1.0.0',
+]
+
+[tool.briefcase.app.resize.linux]
+requires = [
+    '../../gtk',
+]
+
+[tool.briefcase.app.resize.windows]
+requires = [
+    '../../winforms',
+]
+
+# Mobile deployments
+[tool.briefcase.app.resize.iOS]
+requires = [
+    '../../iOS',
+    'std-nslog>=1.0.0',
+]
+
+[tool.briefcase.app.resize.android]
+requires = [
+    '../../android',
+]
+
+# Web deployment
+[tool.briefcase.app.resize.web]
+requires = [
+    '../../web',
+]
+style_framework = "Bootstrap v4.6"

examples/resize/src/resize/__main__.py

@@ -0,0 +1,4 @@
+from resize.app import main
+
+if __name__ == "__main__":
+    main().main_loop()

examples/resize/src/resize/app.py

@@ -0,0 +1,99 @@
+import toga
+from toga.style import Pack
+from toga.style.pack import COLUMN, ROW
+
+
+class SizeButton(toga.Button):
+    def __init__(self, text, *, value, max, on_press):
+        self.value = value
+        self.max = max
+        self.on_press_impl = on_press
+        super().__init__(text, on_press=self.on_press_wrapper)
+
+    def on_press_wrapper(self, button):
+        self.value = (self.value + 1) % (self.max + 1)
+        self.on_press_impl(button)
+
+
+class SizePanel(toga.Box):
+    def __init__(self, title, *, on_change):
+        self.on_change = on_change
+        self.width, self.height = (
+            SizeButton(text, value=1, max=6, on_press=self.on_press)
+            for text in ["W", "H"]
+        )
+        self.flex = SizeButton("F", value=0, max=3, on_press=self.on_press)
+        super().__init__(
+            style=Pack(direction=COLUMN, alignment="center"),
+            children=[
+                toga.Label(title.upper(), style=Pack(font_weight="bold")),
+                toga.Box(
+                    style=Pack(direction=ROW),
+                    children=[self.width, self.height, self.flex],
+                ),
+            ],
+        )
+        self.on_press(None)
+
+    def on_press(self, button):
+        self.on_change(self, self.width.value, self.height.value, self.flex.value)
+
+
+class Resize(toga.App):
+    def startup(self):
+        self.text_label, self.style_label = (
+            toga.Label("", style=Pack(background_color="cyan")) for i in range(2)
+        )
+        main_box = toga.Box(
+            style=Pack(direction=COLUMN),
+            children=[
+                toga.Box(
+                    style=Pack(direction=ROW),
+                    children=[
+                        SizePanel("Text", on_change=self.on_change_text),
+                        toga.Box(style=Pack(flex=1)),
+                        SizePanel("Style", on_change=self.on_change_style),
+                    ],
+                ),
+                toga.Box(
+                    style=Pack(direction=ROW),
+                    children=[
+                        self.text_label,
+                        toga.Label("", style=Pack(background_color="pink", flex=1)),
+                        toga.Label("", style=Pack(background_color="yellow", flex=1)),
+                        self.style_label,
+                    ],
+                ),
+                toga.Box(style=Pack(background_color="pink", flex=1)),
+                toga.Box(style=Pack(background_color="yellow", flex=1)),
+            ],
+        )
+
+        self.main_window = toga.MainWindow(title=self.formal_name)
+        self.main_window.content = main_box
+        self.main_window.show()
+
+    def on_change_text(self, panel, width, height, flex):
+        text = "\n".join(" ".join("X" for i in range(width)) for j in range(height))
+        setattr_if_changed(self.text_label, "text", text)
+        setattr_if_changed(self.text_label.style, "flex", flex)
+
+    def on_change_style(self, panel, width, height, flex):
+        # Increment should be large enough that the minimum window width can be determined
+        # by either the buttons or the labels, depending on the labels' size.
+        INCREMENT = 70
+        setattr_if_changed(self.style_label.style, "width", width * INCREMENT)
+        setattr_if_changed(self.style_label.style, "height", height * INCREMENT)
+        setattr_if_changed(self.style_label.style, "flex", flex)
+
+
+def setattr_if_changed(obj, name, value):
+    """Ensure that each button click only changes one thing."""
+
+    old_value = getattr(obj, name)
+    if old_value != value:
+        setattr(obj, name, value)
+
+
+def main():
+    return Resize()