Add DeviceConfig flag for drag direction angle threshold for cursor drag

Bug: 160786691
Test: Manual and unit tests
  atest FrameworksCoreTests:EditorTouchStateTest
  atest FrameworksCoreTests:EditorCursorDragTest
Change-Id: Ib2e88fbdce4f901772d73bc7ee60483c98e02509

core/java/android/widget/Editor.java

@@ -385,6 +385,7 @@ public class Editor {
     private final SuggestionHelper mSuggestionHelper = new SuggestionHelper();
 
     private boolean mFlagCursorDragFromAnywhereEnabled;
+    private float mCursorDragDirectionMinXYRatio;
     private boolean mFlagInsertionHandleGesturesEnabled;
 
     // Specifies whether the new magnifier (with fish-eye effect) is enabled.
@@ -425,6 +426,11 @@ public class Editor {
         mFlagCursorDragFromAnywhereEnabled = AppGlobals.getIntCoreSetting(
                 WidgetFlags.KEY_ENABLE_CURSOR_DRAG_FROM_ANYWHERE,
                 WidgetFlags.ENABLE_CURSOR_DRAG_FROM_ANYWHERE_DEFAULT ? 1 : 0) != 0;
+        final int cursorDragMinAngleFromVertical = AppGlobals.getIntCoreSetting(
+                WidgetFlags.KEY_CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL,
+                WidgetFlags.CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL_DEFAULT);
+        mCursorDragDirectionMinXYRatio = EditorTouchState.getXYRatio(
+                cursorDragMinAngleFromVertical);
         mFlagInsertionHandleGesturesEnabled = AppGlobals.getIntCoreSetting(
                 WidgetFlags.KEY_ENABLE_INSERTION_HANDLE_GESTURES,
                 WidgetFlags.ENABLE_INSERTION_HANDLE_GESTURES_DEFAULT ? 1 : 0) != 0;
@@ -437,6 +443,8 @@ public class Editor {
         if (TextView.DEBUG_CURSOR) {
             logCursor("Editor", "Cursor drag from anywhere is %s.",
                     mFlagCursorDragFromAnywhereEnabled ? "enabled" : "disabled");
+            logCursor("Editor", "Cursor drag min angle from vertical is %d (= %f x/y ratio)",
+                    cursorDragMinAngleFromVertical, mCursorDragDirectionMinXYRatio);
             logCursor("Editor", "Insertion handle gestures is %s.",
                     mFlagInsertionHandleGesturesEnabled ? "enabled" : "disabled");
             logCursor("Editor", "New magnifier is %s.",
@@ -462,6 +470,11 @@ public class Editor {
         mFlagCursorDragFromAnywhereEnabled = enabled;
     }
 
+    @VisibleForTesting
+    public void setCursorDragMinAngleFromVertical(int degreesFromVertical) {
+        mCursorDragDirectionMinXYRatio = EditorTouchState.getXYRatio(degreesFromVertical);
+    }
+
     @VisibleForTesting
     public boolean getFlagInsertionHandleGesturesEnabled() {
         return mFlagInsertionHandleGesturesEnabled;
@@ -6127,10 +6140,11 @@ public class Editor {
                     if (mIsDraggingCursor) {
                         performCursorDrag(event);
                     } else if (mFlagCursorDragFromAnywhereEnabled
-                                && mTextView.getLayout() != null
+                            && mTextView.getLayout() != null
-                                && mTextView.isFocused()
+                            && mTextView.isFocused()
-                                && mTouchState.isMovedEnoughForDrag()
+                            && mTouchState.isMovedEnoughForDrag()
-                                && !mTouchState.isDragCloseToVertical()) {
+                            && (mTouchState.getInitialDragDirectionXYRatio()
+                            > mCursorDragDirectionMinXYRatio || mTouchState.isOnHandle())) {
                         startCursorDrag(event);
                     }
                     break;

core/java/android/widget/EditorTouchState.java

@@ -59,7 +59,7 @@ public class EditorTouchState {
     private boolean mMultiTapInSameArea;
 
     private boolean mMovedEnoughForDrag;
-    private boolean mIsDragCloseToVertical;
+    private float mInitialDragDirectionXYRatio;
 
     public float getLastDownX() {
         return mLastDownX;
@@ -98,8 +98,23 @@ public class EditorTouchState {
         return mMovedEnoughForDrag;
     }
 
-    public boolean isDragCloseToVertical() {
+    /**
-        return mIsDragCloseToVertical && !mIsOnHandle;
+     * When {@link #isMovedEnoughForDrag()} is {@code true}, this function returns the x/y ratio for
+     * the initial drag direction. Smaller values indicate that the direction is closer to vertical,
+     * while larger values indicate that the direction is closer to horizontal. For example:
+     * <ul>
+     *     <li>if the drag direction is exactly vertical, this returns 0
+     *     <li>if the drag direction is exactly horizontal, this returns {@link Float#MAX_VALUE}
+     *     <li>if the drag direction is 45 deg from vertical, this returns 1
+     *     <li>if the drag direction is 30 deg from vertical, this returns 0.58 (x delta is smaller
+     *     than y delta)
+     *     <li>if the drag direction is 60 deg from vertical, this returns 1.73 (x delta is bigger
+     *     than y delta)
+     * </ul>
+     * This function never returns negative values, regardless of the direction of the drag.
+     */
+    public float getInitialDragDirectionXYRatio() {
+        return mInitialDragDirectionXYRatio;
     }
 
     public void setIsOnHandle(boolean onHandle) {
@@ -155,7 +170,7 @@ public class EditorTouchState {
             mLastDownY = event.getY();
             mLastDownMillis = event.getEventTime();
             mMovedEnoughForDrag = false;
-            mIsDragCloseToVertical = false;
+            mInitialDragDirectionXYRatio = 0.0f;
         } else if (action == MotionEvent.ACTION_UP) {
             if (TextView.DEBUG_CURSOR) {
                 logCursor("EditorTouchState", "ACTION_UP");
@@ -164,7 +179,7 @@ public class EditorTouchState {
             mLastUpY = event.getY();
             mLastUpMillis = event.getEventTime();
             mMovedEnoughForDrag = false;
-            mIsDragCloseToVertical = false;
+            mInitialDragDirectionXYRatio = 0.0f;
         } else if (action == MotionEvent.ACTION_MOVE) {
             if (!mMovedEnoughForDrag) {
                 float deltaX = event.getX() - mLastDownX;
@@ -174,9 +189,8 @@ public class EditorTouchState {
                 int touchSlop = config.getScaledTouchSlop();
                 mMovedEnoughForDrag = distanceSquared > touchSlop * touchSlop;
                 if (mMovedEnoughForDrag) {
-                    // If the direction of the swipe motion is within 45 degrees of vertical, it is
+                    mInitialDragDirectionXYRatio = (deltaY == 0) ? Float.MAX_VALUE :
-                    // considered a vertical drag.
+                            Math.abs(deltaX / deltaY);
-                    mIsDragCloseToVertical = Math.abs(deltaX) <= Math.abs(deltaY);
                 }
             }
         } else if (action == MotionEvent.ACTION_CANCEL) {
@@ -185,7 +199,7 @@ public class EditorTouchState {
             mMultiTapStatus = MultiTapStatus.NONE;
             mMultiTapInSameArea = false;
             mMovedEnoughForDrag = false;
-            mIsDragCloseToVertical = false;
+            mInitialDragDirectionXYRatio = 0.0f;
         }
     }
 
@@ -201,4 +215,27 @@ public class EditorTouchState {
         float distanceSquared = (deltaX * deltaX) + (deltaY * deltaY);
         return distanceSquared <= maxDistance * maxDistance;
     }
+
+    /**
+     * Returns the x/y ratio corresponding to the given angle relative to vertical. Smaller angle
+     * values (ie, closer to vertical) will result in a smaller x/y ratio. For example:
+     * <ul>
+     *     <li>if the angle is 45 deg, the ratio is 1
+     *     <li>if the angle is 30 deg, the ratio is 0.58 (x delta is smaller than y delta)
+     *     <li>if the angle is 60 deg, the ratio is 1.73 (x delta is bigger than y delta)
+     * </ul>
+     * If the passed-in value is <= 0, this function returns 0. If the passed-in value is >= 90,
+     * this function returns {@link Float#MAX_VALUE}.
+     *
+     * @see #getInitialDragDirectionXYRatio()
+     */
+    public static float getXYRatio(int angleFromVerticalInDegrees) {
+        if (angleFromVerticalInDegrees <= 0) {
+            return 0.0f;
+        }
+        if (angleFromVerticalInDegrees >= 90) {
+            return Float.MAX_VALUE;
+        }
+        return (float) Math.tan(Math.toRadians(angleFromVerticalInDegrees));
+    }
 }

core/java/android/widget/WidgetFlags.java

@@ -40,6 +40,28 @@ public final class WidgetFlags {
      */
     public static final boolean ENABLE_CURSOR_DRAG_FROM_ANYWHERE_DEFAULT = true;
 
+    /**
+     * Threshold for the direction of a swipe gesture in order for it to be handled as a cursor drag
+     * rather than a scroll. The direction angle of the swipe gesture must exceed this value in
+     * order to trigger cursor drag; otherwise, the swipe will be assumed to be a scroll gesture.
+     * The value units for this flag is degrees and the valid range is [0,90] inclusive. If a value
+     * < 0 is set, 0 will be used instead; if a value > 90 is set, 90 will be used instead.
+     */
+    public static final String CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL =
+            "CursorControlFeature__min_angle_from_vertical_to_start_cursor_drag";
+
+    /**
+     * The key used in app core settings for the flag
+     * {@link #CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL}.
+     */
+    public static final String KEY_CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL =
+            "widget__min_angle_from_vertical_to_start_cursor_drag";
+
+    /**
+     * Default value for the flag {@link #CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL}.
+     */
+    public static final int CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL_DEFAULT = 45;
+
     /**
      * The flag of finger-to-cursor distance in DP for cursor dragging.
      * The value unit is DP and the range is {0..100}. If the value is out of range, the legacy

core/tests/coretests/src/android/widget/EditorCursorDragTest.java

@@ -200,6 +200,38 @@ public class EditorCursorDragTest {
         onView(withId(R.id.textview)).check(hasInsertionPointerAtIndex(index));
     }
 
+    @Test
+    public void testCursorDrag_diagonal_thresholdConfig() throws Throwable {
+        TextView tv = mActivity.findViewById(R.id.textview);
+        Editor editor = tv.getEditorForTesting();
+
+        StringBuilder sb = new StringBuilder();
+        for (int i = 1; i <= 9; i++) {
+            sb.append("here is some text").append(i).append("\n");
+        }
+        sb.append(Strings.repeat("abcdefghij\n", 400)).append("Last");
+        String text = sb.toString();
+        onView(withId(R.id.textview)).perform(replaceText(text));
+
+        int index = text.indexOf("text9");
+        onView(withId(R.id.textview)).perform(clickOnTextAtIndex(index));
+        onView(withId(R.id.textview)).check(hasInsertionPointerAtIndex(index));
+
+        // Configure the drag direction threshold to require the drag to be exactly horizontal. With
+        // this set, a swipe that is slightly off horizontal should not trigger cursor drag.
+        editor.setCursorDragMinAngleFromVertical(90);
+        int startIdx = text.indexOf("5");
+        int endIdx = text.indexOf("here is some text3");
+        onView(withId(R.id.textview)).perform(dragOnText(startIdx, endIdx));
+        onView(withId(R.id.textview)).check(hasInsertionPointerAtIndex(index));
+
+        // Configure the drag direction threshold to require the drag to be 45 degrees or more from
+        // vertical. With this set, the same swipe gesture as above should now trigger cursor drag.
+        editor.setCursorDragMinAngleFromVertical(45);
+        onView(withId(R.id.textview)).perform(dragOnText(startIdx, endIdx));
+        onView(withId(R.id.textview)).check(hasInsertionPointerAtIndex(endIdx));
+    }
+
     @Test
     public void testCursorDrag_vertical_whenTextViewContentsFitOnScreen() throws Throwable {
         String text = "012345_aaa\n"

core/tests/coretests/src/android/widget/EditorTouchStateTest.java

@@ -165,7 +165,7 @@ public class EditorTouchStateTest {
         long event2Time = 1001;
         MotionEvent event2 = moveEvent(event1Time, event2Time, 200f, 31f);
         mTouchState.update(event2, mConfig);
-        assertDrag(mTouchState, 20f, 30f, 0, 0, false);
+        assertDrag(mTouchState, 20f, 30f, 0, 0, 180f);
 
         // Simulate an ACTION_UP event with a delay that's longer than the double-tap timeout.
         long event3Time = 5000;
@@ -280,7 +280,7 @@ public class EditorTouchStateTest {
         long event3Time = 1002;
         MotionEvent event3 = moveEvent(event3Time, event3Time, newX, newY);
         mTouchState.update(event3, mConfig);
-        assertDrag(mTouchState, 20f, 30f, 0, 0, false);
+        assertDrag(mTouchState, 20f, 30f, 0, 0, Float.MAX_VALUE);
 
         // Simulate an ACTION_UP event.
         long event4Time = 1003;
@@ -301,15 +301,15 @@ public class EditorTouchStateTest {
         long event2Time = 1002;
         MotionEvent event2 = moveEvent(event1Time, event2Time, 100f, 174f);
         mTouchState.update(event2, mConfig);
-        assertDrag(mTouchState, 0f, 0f, 0, 0, true);
+        assertDrag(mTouchState, 0f, 0f, 0, 0, 100f / 174f);
 
         // Simulate another ACTION_MOVE event that is horizontal from the original down event.
-        // The value of `isDragCloseToVertical` should NOT change since it should only reflect the
+        // The drag direction ratio should NOT change since it should only reflect the initial
-        // initial direction of movement.
+        // direction of movement.
         long event3Time = 1003;
         MotionEvent event3 = moveEvent(event1Time, event3Time, 200f, 0f);
         mTouchState.update(event3, mConfig);
-        assertDrag(mTouchState, 0f, 0f, 0, 0, true);
+        assertDrag(mTouchState, 0f, 0f, 0, 0, 100f / 174f);
 
         // Simulate an ACTION_UP event.
         long event4Time = 1004;
@@ -330,15 +330,15 @@ public class EditorTouchStateTest {
         long event2Time = 1002;
         MotionEvent event2 = moveEvent(event1Time, event2Time, 100f, 90f);
         mTouchState.update(event2, mConfig);
-        assertDrag(mTouchState, 0f, 0f, 0, 0, false);
+        assertDrag(mTouchState, 0f, 0f, 0, 0, 100f / 90f);
 
         // Simulate another ACTION_MOVE event that is vertical from the original down event.
-        // The value of `isDragCloseToVertical` should NOT change since it should only reflect the
+        // The drag direction ratio should NOT change since it should only reflect the initial
-        // initial direction of movement.
+        // direction of movement.
         long event3Time = 1003;
         MotionEvent event3 = moveEvent(event1Time, event3Time, 0f, 200f);
         mTouchState.update(event3, mConfig);
-        assertDrag(mTouchState, 0f, 0f, 0, 0, false);
+        assertDrag(mTouchState, 0f, 0f, 0, 0, 100f / 90f);
 
         // Simulate an ACTION_UP event.
         long event4Time = 1004;
@@ -374,7 +374,7 @@ public class EditorTouchStateTest {
         long event2Time = 1002;
         MotionEvent event2 = moveEvent(event2Time, event2Time, 200f, 30f);
         mTouchState.update(event2, mConfig);
-        assertDrag(mTouchState, 20f, 30f, 0, 0, false);
+        assertDrag(mTouchState, 20f, 30f, 0, 0, Float.MAX_VALUE);
 
         // Simulate an ACTION_CANCEL event.
         long event3Time = 1003;
@@ -411,6 +411,84 @@ public class EditorTouchStateTest {
         assertSingleTap(mTouchState, 22f, 33f, 20f, 30f);
     }
 
+    @Test
+    public void testGetXYRatio() throws Exception {
+        doTestGetXYRatio(-1, 0.0f);
+        doTestGetXYRatio(0, 0.0f);
+        doTestGetXYRatio(30, 0.58f);
+        doTestGetXYRatio(45, 1.0f);
+        doTestGetXYRatio(60, 1.73f);
+        doTestGetXYRatio(90, Float.MAX_VALUE);
+        doTestGetXYRatio(91, Float.MAX_VALUE);
+    }
+
+    private void doTestGetXYRatio(int angleFromVerticalInDegrees, float expectedXYRatioRounded) {
+        float result = EditorTouchState.getXYRatio(angleFromVerticalInDegrees);
+        String msg = String.format(
+                "%d deg should give an x/y ratio of %f; actual unrounded result is %f",
+                angleFromVerticalInDegrees, expectedXYRatioRounded, result);
+        float roundedResult = (result == 0.0f || result == Float.MAX_VALUE) ? result :
+                Math.round(result * 100) / 100f;
+        assertThat(msg, roundedResult, is(expectedXYRatioRounded));
+    }
+
+    @Test
+    public void testUpdate_dragDirection() throws Exception {
+        // Simulate moving straight up.
+        doTestDragDirection(100f, 100f, 100f, 50f, 0f);
+
+        // Simulate moving straight down.
+        doTestDragDirection(100f, 100f, 100f, 150f, 0f);
+
+        // Simulate moving straight left.
+        doTestDragDirection(100f, 100f, 50f, 100f, Float.MAX_VALUE);
+
+        // Simulate moving straight right.
+        doTestDragDirection(100f, 100f, 150f, 100f, Float.MAX_VALUE);
+
+        // Simulate moving up and right, < 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 110f, 50f, 10f / 50f);
+
+        // Simulate moving up and right, > 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 150f, 90f, 50f / 10f);
+
+        // Simulate moving down and right, < 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 110f, 150f, 10f / 50f);
+
+        // Simulate moving down and right, > 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 150f, 110f, 50f / 10f);
+
+        // Simulate moving down and left, < 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 90f, 150f, 10f / 50f);
+
+        // Simulate moving down and left, > 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 50f, 110f, 50f / 10f);
+
+        // Simulate moving up and left, < 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 90f, 50f, 10f / 50f);
+
+        // Simulate moving up and left, > 45 deg from vertical.
+        doTestDragDirection(100f, 100f, 50f, 90f, 50f / 10f);
+    }
+
+    private void doTestDragDirection(float downX, float downY, float moveX, float moveY,
+            float expectedInitialDragDirectionXYRatio) {
+        EditorTouchState touchState = new EditorTouchState();
+
+        // Simulate an ACTION_DOWN event.
+        long event1Time = 1001;
+        MotionEvent event1 = downEvent(event1Time, event1Time, downX, downY);
+        touchState.update(event1, mConfig);
+
+        // Simulate an ACTION_MOVE event.
+        long event2Time = 1002;
+        MotionEvent event2 = moveEvent(event1Time, event2Time, moveX, moveY);
+        touchState.update(event2, mConfig);
+        String msg = String.format("(%.0f,%.0f)=>(%.0f,%.0f)", downX, downY, moveX, moveY);
+        assertThat(msg, touchState.getInitialDragDirectionXYRatio(),
+                is(expectedInitialDragDirectionXYRatio));
+    }
+
     private static MotionEvent downEvent(long downTime, long eventTime, float x, float y) {
         return MotionEvent.obtain(downTime, eventTime, MotionEvent.ACTION_DOWN, x, y, 0);
     }
@@ -441,7 +519,7 @@ public class EditorTouchStateTest {
     }
 
     private static void assertDrag(EditorTouchState touchState, float lastDownX,
-            float lastDownY, float lastUpX, float lastUpY, boolean isDragCloseToVertical) {
+            float lastDownY, float lastUpX, float lastUpY, float initialDragDirectionXYRatio) {
         assertThat(touchState.getLastDownX(), is(lastDownX));
         assertThat(touchState.getLastDownY(), is(lastDownY));
         assertThat(touchState.getLastUpX(), is(lastUpX));
@@ -451,7 +529,7 @@ public class EditorTouchStateTest {
         assertThat(touchState.isMultiTap(), is(false));
         assertThat(touchState.isMultiTapInSameArea(), is(false));
         assertThat(touchState.isMovedEnoughForDrag(), is(true));
-        assertThat(touchState.isDragCloseToVertical(), is(isDragCloseToVertical));
+        assertThat(touchState.getInitialDragDirectionXYRatio(), is(initialDragDirectionXYRatio));
     }
 
     private static void assertMultiTap(EditorTouchState touchState,
@@ -467,6 +545,5 @@ public class EditorTouchStateTest {
                 || multiTapStatus == MultiTapStatus.TRIPLE_CLICK));
         assertThat(touchState.isMultiTapInSameArea(), is(isMultiTapInSameArea));
         assertThat(touchState.isMovedEnoughForDrag(), is(false));
-        assertThat(touchState.isDragCloseToVertical(), is(false));
     }
 }

services/core/java/com/android/server/am/CoreSettingsObserver.java

@@ -115,6 +115,10 @@ final class CoreSettingsObserver extends ContentObserver {
                 DeviceConfig.NAMESPACE_WIDGET, WidgetFlags.ENABLE_CURSOR_DRAG_FROM_ANYWHERE,
                 WidgetFlags.KEY_ENABLE_CURSOR_DRAG_FROM_ANYWHERE, boolean.class,
                 WidgetFlags.ENABLE_CURSOR_DRAG_FROM_ANYWHERE_DEFAULT));
+        sDeviceConfigEntries.add(new DeviceConfigEntry<Integer>(
+                DeviceConfig.NAMESPACE_WIDGET, WidgetFlags.CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL,
+                WidgetFlags.KEY_CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL, int.class,
+                WidgetFlags.CURSOR_DRAG_MIN_ANGLE_FROM_VERTICAL_DEFAULT));
         sDeviceConfigEntries.add(new DeviceConfigEntry<Integer>(
                 DeviceConfig.NAMESPACE_WIDGET, WidgetFlags.FINGER_TO_CURSOR_DISTANCE,
                 WidgetFlags.KEY_FINGER_TO_CURSOR_DISTANCE, int.class,