From 93e23c58dc0c7dd997f20734dafdf37802854f2c Mon Sep 17 00:00:00 2001
From: Hawkwood Glazier <jglazier@google.com>
Date: Thu, 11 May 2023 23:02:45 +0000
Subject: [PATCH] Prevent alpha transitions from clipping out-of-bounds clocks

In order to do this, we bypass the default alpha mechaism used by views,
and call saveLayerAlpha ourselves on several views. This allows us to
set bounds for this area outside of the measured bounds.

Clipping still appears to occur after a user switch. b/282226587 will
track that follow up issue.

This is effectively a revert of Ia73ea00920ca0147e0acc5d2919b457203b7575e

Bug: 280113068
Bug: 281697986
Test: Manually checked several transitions
Change-Id: I9112efab88facd0f32daa5cd7377b8184658c159
---
 .../layout/keyguard_clock_switch.xml          |  4 +-
 .../layout/keyguard_status_view.xml           |  4 +-
 .../android/keyguard/KeyguardClockFrame.kt    | 39 +++++++++++++++++++
 .../android/keyguard/KeyguardClockSwitch.java | 20 ++++++++--
 .../KeyguardClockSwitchController.java        | 14 -------
 .../keyguard/KeyguardStatusContainer.kt       | 24 ++++++++++++
 .../android/keyguard/KeyguardStatusView.java  | 38 +++++++-----------
 .../KeyguardStatusViewController.java         |  3 +-
 .../KeyguardClockSwitchControllerTest.java    | 14 +------
 .../keyguard/KeyguardStatusViewTest.kt        | 27 ++++---------
 10 files changed, 107 insertions(+), 80 deletions(-)
 create mode 100644 packages/SystemUI/src/com/android/keyguard/KeyguardClockFrame.kt
 create mode 100644 packages/SystemUI/src/com/android/keyguard/KeyguardStatusContainer.kt

diff --git a/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml b/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml
index 4b9470728dc64..3fc0965f4a813 100644
--- a/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml
+++ b/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml
@@ -25,7 +25,7 @@
     android:layout_height="wrap_content"
     android:clipChildren="false"
     android:layout_gravity="center_horizontal|top">
-    <FrameLayout
+    <com.android.keyguard.KeyguardClockFrame
         android:id="@+id/lockscreen_clock_view"
         android:layout_width="wrap_content"
         android:layout_height="@dimen/small_clock_height"
@@ -34,7 +34,7 @@
         android:clipChildren="false"
         android:paddingStart="@dimen/clock_padding_start"
         android:visibility="invisible" />
-    <FrameLayout
+    <com.android.keyguard.KeyguardClockFrame
         android:id="@+id/lockscreen_clock_view_large"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
diff --git a/packages/SystemUI/res-keyguard/layout/keyguard_status_view.xml b/packages/SystemUI/res-keyguard/layout/keyguard_status_view.xml
index 647abee9a99b0..557fbf21d5c48 100644
--- a/packages/SystemUI/res-keyguard/layout/keyguard_status_view.xml
+++ b/packages/SystemUI/res-keyguard/layout/keyguard_status_view.xml
@@ -30,7 +30,7 @@
     android:clipChildren="false"
     android:layout_width="0dp"
     android:layout_height="wrap_content">
-    <LinearLayout
+    <com.android.keyguard.KeyguardStatusContainer
         android:id="@+id/status_view_container"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
@@ -48,5 +48,5 @@
             android:layout_height="wrap_content"
             android:padding="@dimen/qs_media_padding"
             />
-    </LinearLayout>
+    </com.android.keyguard.KeyguardStatusContainer>
 </com.android.keyguard.KeyguardStatusView>
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockFrame.kt b/packages/SystemUI/src/com/android/keyguard/KeyguardClockFrame.kt
new file mode 100644
index 0000000000000..d821d309adde7
--- /dev/null
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockFrame.kt
@@ -0,0 +1,39 @@
+package com.android.keyguard
+
+import android.content.Context
+import android.graphics.Canvas
+import android.util.AttributeSet
+import android.view.View
+import android.widget.FrameLayout
+
+class KeyguardClockFrame(
+    context: Context,
+    attrs: AttributeSet,
+) : FrameLayout(context, attrs) {
+    private var drawAlpha: Int = 255
+
+    protected override fun onSetAlpha(alpha: Int): Boolean {
+        drawAlpha = alpha
+        return true
+    }
+
+    protected override fun dispatchDraw(canvas: Canvas) {
+        val restoreTo = saveCanvasAlpha(this, canvas, drawAlpha)
+        super.dispatchDraw(canvas)
+        canvas.restoreToCount(restoreTo)
+    }
+
+    companion object {
+        @JvmStatic
+        fun saveCanvasAlpha(view: View, canvas: Canvas, alpha: Int): Int {
+            var (x, y) =
+                run {
+                    val locationOnScreen = IntArray(2)
+                    view.getLocationOnScreen(locationOnScreen)
+                    Pair(locationOnScreen[0].toFloat(), locationOnScreen[1].toFloat())
+                }
+
+            return canvas.saveLayerAlpha(-1f * x, -1f * y, x + view.width, y + view.height, alpha)
+        }
+    }
+}
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
index 644a9bcdd588f..05a8f9fc9ae2d 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
@@ -5,11 +5,11 @@ import android.animation.AnimatorListenerAdapter;
 import android.animation.AnimatorSet;
 import android.animation.ObjectAnimator;
 import android.content.Context;
+import android.graphics.Canvas;
 import android.graphics.Rect;
 import android.util.AttributeSet;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.FrameLayout;
 import android.widget.RelativeLayout;
 
 import androidx.annotation.IntDef;
@@ -69,12 +69,13 @@ public class KeyguardClockSwitch extends RelativeLayout {
     /**
      * Frame for small/large clocks
      */
-    private FrameLayout mSmallClockFrame;
-    private FrameLayout mLargeClockFrame;
+    private KeyguardClockFrame mSmallClockFrame;
+    private KeyguardClockFrame mLargeClockFrame;
     private ClockController mClock;
 
     private View mStatusArea;
     private int mSmartspaceTopOffset;
+    private int mDrawAlpha = 255;
 
     /**
      * Maintain state so that a newly connected plugin can be initialized.
@@ -121,6 +122,19 @@ public class KeyguardClockSwitch extends RelativeLayout {
         onDensityOrFontScaleChanged();
     }
 
+    @Override
+    protected boolean onSetAlpha(int alpha) {
+        mDrawAlpha = alpha;
+        return true;
+    }
+
+    @Override
+    protected void dispatchDraw(Canvas canvas) {
+        int restoreTo = KeyguardClockFrame.saveCanvasAlpha(this, canvas, mDrawAlpha);
+        super.dispatchDraw(canvas);
+        canvas.restoreToCount(restoreTo);
+    }
+
     public void setLogBuffer(LogBuffer logBuffer) {
         mLogBuffer = logBuffer;
     }
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
index 676f342775efa..d8bf570954df6 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
@@ -178,20 +178,6 @@ public class KeyguardClockSwitchController extends ViewController<KeyguardClockS
         }
     }
 
-    /**
-     * Set alpha directly to mView will clip clock, so we set alpha to clock face instead
-     */
-    public void setAlpha(float alpha) {
-        ClockController clock = getClock();
-        if (clock != null) {
-            clock.getLargeClock().getView().setAlpha(alpha);
-            clock.getSmallClock().getView().setAlpha(alpha);
-        }
-        if (mStatusArea != null) {
-            mStatusArea.setAlpha(alpha);
-        }
-    }
-
     /**
      * Attach the controller to the view it relates to.
      */
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardStatusContainer.kt b/packages/SystemUI/src/com/android/keyguard/KeyguardStatusContainer.kt
new file mode 100644
index 0000000000000..d885892ec0abb
--- /dev/null
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardStatusContainer.kt
@@ -0,0 +1,24 @@
+package com.android.keyguard
+
+import android.content.Context
+import android.graphics.Canvas
+import android.util.AttributeSet
+import android.widget.LinearLayout
+
+class KeyguardStatusContainer(
+    context: Context,
+    attrs: AttributeSet,
+) : LinearLayout(context, attrs) {
+    private var drawAlpha: Int = 255
+
+    protected override fun onSetAlpha(alpha: Int): Boolean {
+        drawAlpha = alpha
+        return true
+    }
+
+    protected override fun dispatchDraw(canvas: Canvas) {
+        val restoreTo = KeyguardClockFrame.saveCanvasAlpha(this, canvas, drawAlpha)
+        super.dispatchDraw(canvas)
+        canvas.restoreToCount(restoreTo)
+    }
+}
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardStatusView.java b/packages/SystemUI/src/com/android/keyguard/KeyguardStatusView.java
index 23136097f41ff..553af5b8fa41e 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardStatusView.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardStatusView.java
@@ -19,6 +19,7 @@ package com.android.keyguard;
 import static java.util.Collections.emptySet;
 
 import android.content.Context;
+import android.graphics.Canvas;
 import android.os.Build;
 import android.os.Trace;
 import android.util.AttributeSet;
@@ -47,6 +48,7 @@ public class KeyguardStatusView extends GridLayout {
     private KeyguardSliceView mKeyguardSlice;
     private View mMediaHostContainer;
 
+    private int mDrawAlpha = 255;
     private float mDarkAmount = 0;
 
     public KeyguardStatusView(Context context) {
@@ -136,30 +138,16 @@ public class KeyguardStatusView extends GridLayout {
         Trace.endSection();
     }
 
-    /**
-     * Clock content will be clipped when goes beyond bounds,
-     * so we setAlpha for all views except clock
-     */
-    public void setAlpha(float alpha, boolean excludeClock) {
-        if (!excludeClock) {
-            setAlpha(alpha);
-            return;
-        }
-        if (alpha == 1 || alpha == 0) {
-            setAlpha(alpha);
-        }
-        for (int i = 0; i < getChildCount(); i++) {
-            View child = getChildAt(i);
-            if (child == mStatusViewContainer) {
-                for (int j = 0; j < mStatusViewContainer.getChildCount(); j++) {
-                    View innerChild = mStatusViewContainer.getChildAt(j);
-                    if (innerChild != mClockView) {
-                        innerChild.setAlpha(alpha);
-                    }
-                }
-            } else {
-                child.setAlpha(alpha);
-            }
-        }
+    @Override
+    protected boolean onSetAlpha(int alpha) {
+        mDrawAlpha = alpha;
+        return true;
+    }
+
+    @Override
+    protected void dispatchDraw(Canvas canvas) {
+        int restoreTo = KeyguardClockFrame.saveCanvasAlpha(this, canvas, mDrawAlpha);
+        super.dispatchDraw(canvas);
+        canvas.restoreToCount(restoreTo);
     }
 }
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardStatusViewController.java b/packages/SystemUI/src/com/android/keyguard/KeyguardStatusViewController.java
index af474661a67d6..794eeda86b0fc 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardStatusViewController.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardStatusViewController.java
@@ -180,8 +180,7 @@ public class KeyguardStatusViewController extends ViewController<KeyguardStatusV
      */
     public void setAlpha(float alpha) {
         if (!mKeyguardVisibilityHelper.isVisibilityAnimating()) {
-            mView.setAlpha(alpha, true);
-            mKeyguardClockSwitchController.setAlpha(alpha);
+            mView.setAlpha(alpha);
         }
     }
 
diff --git a/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java b/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java
index d8e2a3842e855..fb738454fc71b 100644
--- a/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java
+++ b/packages/SystemUI/tests/src/com/android/keyguard/KeyguardClockSwitchControllerTest.java
@@ -134,7 +134,6 @@ public class KeyguardClockSwitchControllerTest extends SysuiTestCase {
 
     private KeyguardClockSwitchController mController;
     private View mSliceView;
-    private LinearLayout mStatusArea;
     private FakeExecutor mExecutor;
 
     @Before
@@ -196,8 +195,8 @@ public class KeyguardClockSwitchControllerTest extends SysuiTestCase {
 
         mSliceView = new View(getContext());
         when(mView.findViewById(R.id.keyguard_slice_view)).thenReturn(mSliceView);
-        mStatusArea = new LinearLayout(getContext());
-        when(mView.findViewById(R.id.keyguard_status_area)).thenReturn(mStatusArea);
+        when(mView.findViewById(R.id.keyguard_status_area)).thenReturn(
+                new LinearLayout(getContext()));
     }
 
     @Test
@@ -402,15 +401,6 @@ public class KeyguardClockSwitchControllerTest extends SysuiTestCase {
         assertNull(mController.getClock());
     }
 
-    @Test
-    public void testSetAlpha_setClockAlphaForCLockFace() {
-        mController.onViewAttached();
-        mController.setAlpha(0.5f);
-        verify(mLargeClockView).setAlpha(0.5f);
-        verify(mSmallClockView).setAlpha(0.5f);
-        assertEquals(0.5f, mStatusArea.getAlpha(), 0.0f);
-    }
-
     private void verifyAttachment(VerificationMode times) {
         verify(mClockRegistry, times).registerClockChangeListener(
                 any(ClockRegistry.ClockChangeListener.class));
diff --git a/packages/SystemUI/tests/src/com/android/keyguard/KeyguardStatusViewTest.kt b/packages/SystemUI/tests/src/com/android/keyguard/KeyguardStatusViewTest.kt
index a8c281c247003..f8262d43cdbb5 100644
--- a/packages/SystemUI/tests/src/com/android/keyguard/KeyguardStatusViewTest.kt
+++ b/packages/SystemUI/tests/src/com/android/keyguard/KeyguardStatusViewTest.kt
@@ -24,46 +24,33 @@ class KeyguardStatusViewTest : SysuiTestCase() {
         get() = keyguardStatusView.findViewById(R.id.status_view_media_container)
     private val statusViewContainer: ViewGroup
         get() = keyguardStatusView.findViewById(R.id.status_view_container)
-    private val clockView: ViewGroup
-        get() = keyguardStatusView.findViewById(R.id.keyguard_clock_container)
     private val childrenExcludingMedia
         get() = statusViewContainer.children.filter { it != mediaView }
 
     @Before
     fun setUp() {
-        keyguardStatusView = LayoutInflater.from(context)
-                .inflate(R.layout.keyguard_status_view, /* root= */ null) as KeyguardStatusView
+        keyguardStatusView =
+            LayoutInflater.from(context).inflate(R.layout.keyguard_status_view, /* root= */ null)
+                as KeyguardStatusView
     }
 
     @Test
     fun setChildrenTranslationYExcludingMediaView_mediaViewIsNotTranslated() {
         val translationY = 1234f
 
-        keyguardStatusView.setChildrenTranslationY(translationY, /* excludeMedia= */true)
+        keyguardStatusView.setChildrenTranslationY(translationY, /* excludeMedia= */ true)
 
         assertThat(mediaView.translationY).isEqualTo(0)
 
-        childrenExcludingMedia.forEach {
-            assertThat(it.translationY).isEqualTo(translationY)
-        }
+        childrenExcludingMedia.forEach { assertThat(it.translationY).isEqualTo(translationY) }
     }
 
     @Test
     fun setChildrenTranslationYIncludeMediaView() {
         val translationY = 1234f
 
-        keyguardStatusView.setChildrenTranslationY(translationY, /* excludeMedia= */false)
+        keyguardStatusView.setChildrenTranslationY(translationY, /* excludeMedia= */ false)
 
-        statusViewContainer.children.forEach {
-            assertThat(it.translationY).isEqualTo(translationY)
-        }
-    }
-
-    @Test
-    fun setAlphaExcludeClock() {
-        keyguardStatusView.setAlpha(0.5f, /* excludeClock= */true)
-        assertThat(statusViewContainer.alpha).isNotEqualTo(0.5f)
-        assertThat(mediaView.alpha).isEqualTo(0.5f)
-        assertThat(clockView.alpha).isNotEqualTo(0.5f)
+        statusViewContainer.children.forEach { assertThat(it.translationY).isEqualTo(translationY) }
     }
 }