[widget audit] toga.MultilineTextInput

.github/workflows/ci.yml

@@ -205,9 +205,21 @@ jobs:
           - backend: linux
             runs-on: ubuntu-22.04
             # The package list should be the same as in tutorial-0.rst, and the BeeWare
-            # tutorial.
-            pre-command: "sudo apt-get update -y && sudo apt-get install -y python3-dev python3-cairo-dev python3-gi-cairo libgirepository1.0-dev libcairo2-dev libpango1.0-dev gir1.2-webkit2-4.0 pkg-config"
-            briefcase-run-prefix: 'xvfb-run -a -s "-screen 0 2048x1536x24"'
+            # tutorial, plus flwm to provide a window manager
+            pre-command: |
+                sudo apt-get update -y && sudo apt-get install -y python3-dev python3-cairo-dev python3-gi-cairo libgirepository1.0-dev libcairo2-dev libpango1.0-dev gir1.2-webkit2-4.0 pkg-config flwm
+
+                # Start Virtual X server
+                echo "Start X server..."
+                Xvfb :99 -screen 0 2048x1536x24 &
+                sleep 1
+
+                # Start Window manager
+                echo "Start window manager..."
+                DISPLAY=:99 flwm &
+                sleep 1
+
+            briefcase-run-prefix: 'DISPLAY=:99'
             setup-python: false  # Use the system Python packages.
 
           - backend: windows

android/src/toga_android/libs/android/drawable.py

@@ -0,0 +1,4 @@
+from rubicon.java import JavaClass
+
+ColorDrawable = JavaClass("android/graphics/drawable/ColorDrawable")
+InsetDrawable = JavaClass("android/graphics/drawable/InsetDrawable")

android/src/toga_android/widgets/base.py

@@ -4,6 +4,8 @@
 
 from ..colors import native_color
 from ..libs.activity import MainActivity
+from ..libs.android.drawable import ColorDrawable, InsetDrawable
+from ..libs.android.graphics import PorterDuff__Mode, PorterDuffColorFilter, Rect
 from ..libs.android.view import Gravity, View
 
 
@@ -109,18 +111,39 @@ def set_font(self, font):
         # By default, font 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. So each widget must decide how to implement this method, possibly
+    # using one of the utility functions below.
     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):
-        if value is None:
-            self.native.setBackgroundColor(native_color(TRANSPARENT))
+    def set_background_simple(self, value):
+        if not hasattr(self, "_default_background"):
+            self._default_background = self.native.getBackground()
+
+        if value in (None, TRANSPARENT):
+            self.native.setBackground(self._default_background)
         else:
-            self.native.setBackgroundColor(native_color(value))
+            background = ColorDrawable(native_color(value))
+            if isinstance(self._default_background, InsetDrawable):
+                outer_padding = Rect()
+                inner_padding = Rect()
+                self._default_background.getPadding(outer_padding)
+                self._default_background.getDrawable().getPadding(inner_padding)
+                insets = [
+                    getattr(outer_padding, name) - getattr(inner_padding, name)
+                    for name in ["left", "top", "right", "bottom"]
+                ]
+                background = InsetDrawable(background, *insets)
+            self.native.setBackground(background)
+
+    def set_background_filter(self, value):
+        self.native.getBackground().setColorFilter(
+            None
+            if value in (None, TRANSPARENT)
+            else PorterDuffColorFilter(native_color(value), PorterDuff__Mode.SRC_IN)
+        )
 
     def set_alignment(self, alignment):
         pass  # If appropriate, a widget subclass will implement this.

android/src/toga_android/widgets/box.py

@@ -20,7 +20,7 @@ def set_child_bounds(self, widget, x, y, width, height):
         self.native.updateViewLayout(widget.native, layout_params)
 
     def set_background_color(self, value):
-        self.set_background_color_simple(value)
+        self.set_background_simple(value)
 
     def rehint(self):
         self.interface.intrinsic.width = at_least(0)

android/src/toga_android/widgets/button.py

@@ -1,9 +1,5 @@
 from travertino.size import at_least
 
-from toga.colors import TRANSPARENT
-from toga_android.colors import native_color
-
-from ..libs.android.graphics import PorterDuff__Mode, PorterDuffColorFilter
 from ..libs.android.view import OnClickListener, View__MeasureSpec
 from ..libs.android.widget import Button as A_Button
 from .label import TextViewWidget
@@ -34,12 +30,7 @@ def set_enabled(self, value):
         self.native.setEnabled(value)
 
     def set_background_color(self, value):
-        # Do not use self.native.setBackgroundColor - this messes with the button style!
-        self.native.getBackground().setColorFilter(
-            None
-            if value is None or value == TRANSPARENT
-            else PorterDuffColorFilter(native_color(value), PorterDuff__Mode.SRC_IN)
-        )
+        self.set_background_filter(value)
 
     def rehint(self):
         # Like other text-viewing widgets, Android crashes when rendering

android/src/toga_android/widgets/label.py

@@ -25,6 +25,18 @@ def set_color(self, value):
         else:
             self.native.setTextColor(native_color(value))
 
+    def set_textview_alignment(self, value, vertical_gravity):
+        # Justified text wasn't added until API level 26.
+        # We only run the test suite on API 31, so we need to disable branch coverage.
+        if Build.VERSION.SDK_INT >= 26:  # pragma: no branch
+            self.native.setJustificationMode(
+                Layout.JUSTIFICATION_MODE_INTER_WORD
+                if value == JUSTIFY
+                else Layout.JUSTIFICATION_MODE_NONE
+            )
+
+        self.native.setGravity(vertical_gravity | align(value))
+
 
 class Label(TextViewWidget):
     def create(self):
@@ -38,7 +50,7 @@ def set_text(self, value):
         self.native.setText(value)
 
     def set_background_color(self, value):
-        self.set_background_color_simple(value)
+        self.set_background_simple(value)
 
     def rehint(self):
         # Refuse to rehint an Android TextView if it has no LayoutParams yet.
@@ -60,19 +72,4 @@ def rehint(self):
         self.interface.intrinsic.width = at_least(self.native.getMeasuredWidth())
 
     def set_alignment(self, value):
-        # 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 API level 26.
-        # We only run the test suite on API 31, so we need to disable branch coverage.
-        if Build.VERSION.SDK_INT >= 26:  # pragma: no branch
-            self.native.setJustificationMode(
-                Layout.JUSTIFICATION_MODE_INTER_WORD
-                if value == JUSTIFY
-                else Layout.JUSTIFICATION_MODE_NONE
-            )
-
-        self.native.setGravity(Gravity.CENTER_VERTICAL | align(value))
+        self.set_textview_alignment(value, Gravity.TOP)

android/src/toga_android/widgets/multilinetextinput.py

@@ -1,71 +1,72 @@
 from travertino.size import at_least
 
-from toga.constants import LEFT
-
 from ..libs.android.text import InputType, TextWatcher
 from ..libs.android.view import Gravity
 from ..libs.android.widget import EditText
-from .base import align
 from .label import TextViewWidget
 
 
 class TogaTextWatcher(TextWatcher):
     def __init__(self, impl):
         super().__init__()
-        self.impl = impl
         self.interface = impl.interface
 
     def beforeTextChanged(self, _charSequence, _start, _count, _after):
         pass
 
     def afterTextChanged(self, _editable):
-        if self.interface.on_change:
-            self.interface.on_change(widget=self.interface)
+        self.interface.on_change(widget=self.interface)
 
     def onTextChanged(self, _charSequence, _start, _before, _count):
         pass
 
 
 class MultilineTextInput(TextViewWidget):
     def create(self):
-        self._textChangedListener = None
         self.native = EditText(self._native_activity)
         self.native.setInputType(
             InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_FLAG_MULTI_LINE
         )
-        # Set default alignment
-        self.set_alignment(LEFT)
+        self.native.addTextChangedListener(TogaTextWatcher(self))
         self.cache_textview_defaults()
 
     def get_value(self):
-        return self.native.getText().toString()
+        return str(self.native.getText())
+
+    def set_value(self, value):
+        self.native.setText(value)
+
+    def get_readonly(self):
+        return not self.native.isFocusable()
 
-    def set_readonly(self, value):
-        self.native.setFocusable(not value)
+    def set_readonly(self, readonly):
+        if readonly:
+            # Implicitly calls setFocusableInTouchMode(False)
+            self.native.setFocusable(False)
+        else:
+            # Implicitly calls setFocusable(True)
+            self.native.setFocusableInTouchMode(True)
+
+    def get_placeholder(self):
+        return str(self.native.getHint())
 
     def set_placeholder(self, value):
-        # Android EditText's setHint() requires a Python string.
-        self.native.setHint(value if value is not None else "")
+        self.native.setHint(value)
 
     def set_alignment(self, value):
-        self.native.setGravity(Gravity.TOP | align(value))
-
-    def set_value(self, value):
-        self.native.setText(value)
+        self.set_textview_alignment(value, Gravity.TOP)
 
-    def set_on_change(self, handler):
-        if self._textChangedListener:
-            self.native.removeTextChangedListener(self._textChangedListener)
-        self._textChangedListener = TogaTextWatcher(self)
-        self.native.addTextChangedListener(self._textChangedListener)
+    def set_background_color(self, value):
+        # This causes any custom color to hide the bottom border line, but it's better
+        # than set_background_filter, which affects *only* the bottom border line.
+        self.set_background_simple(value)
 
     def rehint(self):
         self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
         self.interface.intrinsic.height = at_least(self.interface._MIN_HEIGHT)
 
     def scroll_to_bottom(self):
-        last_line = (self.native.getLineCount() - 1) * self.native.getLineHeight()
-        self.native.scrollTo(0, last_line)
+        self.native.setSelection(self.native.length())
 
     def scroll_to_top(self):
-        self.native.scrollTo(0, 0)
+        self.native.setSelection(0)

android/src/toga_android/widgets/textinput.py

@@ -5,7 +5,6 @@
 from ..libs.android.text import InputType, TextWatcher
 from ..libs.android.view import Gravity, OnKeyListener, View__MeasureSpec
 from ..libs.android.widget import EditText
-from .base import align
 from .label import TextViewWidget
 
 
@@ -64,12 +63,7 @@ def set_placeholder(self, value):
         self.native.setHint(value if value is not None else "")
 
     def set_alignment(self, value):
-        # Refuse to set alignment unless widget has been added to a container.
-        # This is because Android EditText requires LayoutParams before
-        # setGravity() can be called.
-        if not self.native.getLayoutParams():
-            return
-        self.native.setGravity(Gravity.CENTER_VERTICAL | align(value))
+        self.set_textview_alignment(value, Gravity.CENTER_VERTICAL)
 
     def set_value(self, value):
         self.native.setText(value)

android/src/toga_android/widgets/webview.py

@@ -3,9 +3,9 @@
 
 from travertino.size import at_least
 
-from ..libs.android.view import Gravity, View__MeasureSpec
+from ..libs.android.view import View__MeasureSpec
 from ..libs.android.webkit import ValueCallback, WebView as A_WebView, WebViewClient
-from .base import Widget, align
+from .base import Widget
 
 
 class ReceiveString(ValueCallback):
@@ -72,13 +72,6 @@ async def evaluate_javascript(self, javascript):
     def invoke_javascript(self, javascript):
         self.native.evaluateJavascript(str(javascript), ReceiveString())
 
-    def set_alignment(self, value):
-        # Refuse to set alignment unless widget has been added to a container.
-        # This is because this widget's setGravity() requires LayoutParams before it can be called.
-        if not self.native.getLayoutParams():
-            return
-        self.native.setGravity(Gravity.CENTER_VERTICAL | align(value))
-
     def rehint(self):
         self.interface.intrinsic.width = at_least(self.interface._MIN_WIDTH)
         # Refuse to call measure() if widget has no container, i.e., has no LayoutParams.

android/tests_backend/widgets/base.py

@@ -3,8 +3,15 @@
 from java import dynamic_proxy
 from pytest import approx
 
+from android.graphics.drawable import (
+    ColorDrawable,
+    DrawableContainer,
+    DrawableWrapper,
+    LayerDrawable,
+)
 from android.os import Build
 from android.view import View, ViewTreeObserver
+from toga.colors import TRANSPARENT
 from toga.fonts import SYSTEM
 from toga.style.pack import JUSTIFY, LEFT
 
@@ -122,7 +129,34 @@ def assert_layout(self, size, position):
 
     @property
     def background_color(self):
-        return toga_color(self.native.getBackground().getColor())
+        background = self.native.getBackground()
+        while True:
+            if isinstance(background, ColorDrawable):
+                return toga_color(background.getColor())
+
+            # The following complex Drawables all apply color filters to their children,
+            # but they don't implement getColorFilter, at least not in our current
+            # minimum API level.
+            elif isinstance(background, LayerDrawable):
+                background = background.getDrawable(0)
+            elif isinstance(background, DrawableContainer):
+                background = background.getCurrent()
+            elif isinstance(background, DrawableWrapper):
+                background = background.getDrawable()
+
+            else:
+                break
+
+        if background is None:
+            return TRANSPARENT
+        filter = background.getColorFilter()
+        if filter:
+            # PorterDuffColorFilter.getColor is undocumented, but continues to work for
+            # now. If this method is blocked in the future, another option is to use the
+            # filter to draw something and see what color comes out.
+            return toga_color(filter.getColor())
+        else:
+            return TRANSPARENT
 
     async def press(self):
         self.native.performClick()