diff --git a/core/res/res/values/dimens.xml b/core/res/res/values/dimens.xml
index 9824051685231..de5fc9511010e 100644
--- a/core/res/res/values/dimens.xml
+++ b/core/res/res/values/dimens.xml
@@ -517,6 +517,7 @@
     <dimen name="item_touch_helper_swipe_escape_max_velocity">800dp</dimen>
 
     <!-- The elevation of AutoFill fill window-->
-    <dimen name="autofill_fill_elevation">2dp</dimen>
+    <dimen name="autofill_fill_elevation">4dp</dimen>
     <dimen name="autofill_fill_item_height">64dp</dimen>
+    <dimen name="autofill_fill_min_margin">16dp</dimen>
 </resources>
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 8f3ba87384067..89269aad8277e 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -2835,6 +2835,7 @@
   <!-- com.android.server.autofill -->
   <java-symbol type="dimen" name="autofill_fill_elevation" />
   <java-symbol type="dimen" name="autofill_fill_item_height" />
+  <java-symbol type="dimen" name="autofill_fill_min_margin" />
   <java-symbol type="layout" name="autofill_save"/>
   <java-symbol type="id" name="autofill_save_title" />
   <java-symbol type="id" name="autofill_save_no" />
diff --git a/services/autofill/java/com/android/server/autofill/AnchoredWindow.java b/services/autofill/java/com/android/server/autofill/AnchoredWindow.java
index c68ac60bb26bb..ed0d234359844 100644
--- a/services/autofill/java/com/android/server/autofill/AnchoredWindow.java
+++ b/services/autofill/java/com/android/server/autofill/AnchoredWindow.java
@@ -17,134 +17,276 @@ package com.android.server.autofill;
 
 import static com.android.server.autofill.Helper.DEBUG;
 
+import android.annotation.Nullable;
 import android.content.Context;
+import android.graphics.PixelFormat;
 import android.graphics.Rect;
+import android.os.IBinder;
 import android.util.Slog;
 import android.view.Gravity;
 import android.view.MotionEvent;
 import android.view.View;
-import android.view.ViewGroup;
+import android.view.View.MeasureSpec;
 import android.view.WindowManager;
 import android.view.WindowManager.LayoutParams;
 import android.widget.FrameLayout;
 
-import java.io.PrintWriter;
 /**
  * A window above the application that is smartly anchored to a rectangular region.
  */
-final class AnchoredWindow {
+final class AnchoredWindow implements View.OnLayoutChangeListener, View.OnTouchListener {
     private static final String TAG = "AutoFill";
 
+    private static final int NULL_HEIGHT = -1;
+
     private final WindowManager mWm;
-    private final View mRootView;
-    private final View mView;
-    private final int mWidth;
-    private final int mHeight;
-    private boolean mIsShowing = false;
+    private final IBinder mAppToken;
+    private final View mContentView;
+
+    private final View mWindowSizeListenerView;
+    private final int mMinMargin;
+
+    private int mLastHeight = NULL_HEIGHT;
+    @Nullable
+    private Rect mLastBounds;
+    @Nullable
+    private Rect mLastDisplayBounds;
 
     /**
      * Constructor.
      *
-     * @param wm window manager that draws the view on a window
-     * @param view singleton view in the window
-     * @param width requested width of the view
-     * @param height requested height of the view
+     * @param wm window manager that draws the content on a window
+     * @param appToken token to pass to window manager
+     * @param contentView content of the window
      */
-    AnchoredWindow(WindowManager wm, View view, int width, int height) {
+    AnchoredWindow(WindowManager wm, IBinder appToken, View contentView) {
         mWm = wm;
-        mRootView = wrapView(view, width, height);
-        mView = view;
-        mWidth = width;
-        mHeight = height;
+        mAppToken = appToken;
+        mContentView = contentView;
+
+        mContentView.addOnLayoutChangeListener(this);
+
+        Context context = contentView.getContext();
+
+        mWindowSizeListenerView = new FrameLayout(context);
+        mWindowSizeListenerView.addOnLayoutChangeListener(this);
+
+        mMinMargin = context.getResources().getDimensionPixelSize(
+                com.android.internal.R.dimen.autofill_fill_min_margin);
     }
 
     /**
      * Shows the window.
      *
-     * @param bounds the rectangular region this window should be anchored to
+     * @param bounds the region the window should be anchored to
      */
     void show(Rect bounds) {
-        final LayoutParams params = createBaseLayoutParams();
-        params.x = bounds.left;
-        params.y = bounds.bottom;
+        if (DEBUG) Slog.d(TAG, "show bounds=" + bounds);
 
-        if (!mIsShowing) {
-            if (DEBUG) Slog.d(TAG, "adding view " + mView);
-            mWm.addView(mRootView, params);
-        } else {
-            if (DEBUG) Slog.d(TAG, "updating view " + mView);
-            mWm.updateViewLayout(mRootView, params);
+        if (!mWindowSizeListenerView.isAttachedToWindow()) {
+            if (DEBUG) Slog.d(TAG, "adding mWindowSizeListenerView");
+            LayoutParams params = createWindowLayoutParams(
+                    mAppToken,
+                    LayoutParams.FLAG_NOT_TOUCHABLE); // not touchable
+            params.gravity = Gravity.LEFT | Gravity.TOP;
+            params.x = 0;
+            params.y = 0;
+            params.width = LayoutParams.MATCH_PARENT;
+            params.height = LayoutParams.MATCH_PARENT;
+            mWm.addView(mWindowSizeListenerView, params);
         }
-        mIsShowing = true;
+
+        updateBounds(bounds);
     }
 
     /**
      * Hides the window.
      */
     void hide() {
-        if (DEBUG) Slog.d(TAG, "removing view " + mView);
+        if (DEBUG) Slog.d(TAG, "hide");
 
-        if (mIsShowing) {
-            mWm.removeView(mRootView);
+        mLastHeight = NULL_HEIGHT;
+        mLastBounds = null;
+        mLastDisplayBounds = null;
+
+        if (mWindowSizeListenerView.isAttachedToWindow()) {
+            if (DEBUG) Slog.d(TAG, "removing mWindowSizeListenerView");
+            mWm.removeView(mWindowSizeListenerView);
         }
-        mIsShowing = false;
-    }
 
-    /**
-     * Wraps a view with a SelfRemovingView and sets its requested width and height.
-     */
-    private View wrapView(View view, int width, int height) {
-        final ViewGroup viewGroup = new SelfRemovingView(view.getContext());
-        viewGroup.addView(view, new ViewGroup.LayoutParams(width, height));
-        return viewGroup;
-    }
-
-    private static LayoutParams createBaseLayoutParams() {
-        final LayoutParams params = new LayoutParams();
-        // TODO(b/33197203): LayoutParams.TYPE_AUTOFILL
-        params.type = LayoutParams.TYPE_SYSTEM_ALERT;
-        params.flags =
-                LayoutParams.SOFT_INPUT_STATE_UNCHANGED
-                | LayoutParams.FLAG_LAYOUT_IN_SCREEN
-                | LayoutParams.FLAG_LAYOUT_NO_LIMITS
-                | LayoutParams.FLAG_NOT_FOCUSABLE
-                | LayoutParams.FLAG_NOT_TOUCH_MODAL
-                | LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH;
-        params.gravity = Gravity.TOP | Gravity.LEFT;
-        params.width = LayoutParams.WRAP_CONTENT;
-        params.height = LayoutParams.WRAP_CONTENT;
-        return params;
+        if (mContentView.isAttachedToWindow()) {
+            if (DEBUG) Slog.d(TAG, "removing mContentView");
+            mContentView.setOnTouchListener(null);
+            mWm.removeView(mContentView);
+        }
     }
 
     @Override
-    public String toString() {
-        if (!DEBUG) return super.toString();
-
-        return "AnchoredWindow: [width=" + mWidth + ", height=" + mHeight + ", view=" + mView + "]";
+    public void onLayoutChange(View view, int left, int top, int right, int bottom,
+            int oldLeft, int oldTop, int oldRight, int oldBottom) {
+        if (view == mWindowSizeListenerView) {
+            if (DEBUG) Slog.d(TAG, "onLayoutChange() for mWindowSizeListenerView");
+            // mWindowSizeListenerView layout changed, get the size of the display bounds and update
+            // the window.
+            final Rect displayBounds = new Rect();
+            view.getBoundsOnScreen(displayBounds);
+            updateDisplayBounds(displayBounds);
+        } else if (view == mContentView) {
+            // mContentView layout changed, update the window in case its height changed.
+            if (DEBUG) Slog.d(TAG, "onLayoutChange() for mContentView");
+            updateHeight();
+        }
     }
 
-    void dump(PrintWriter pw) {
-        pw.println("Anchored Window");
-        final String prefix = "  ";
-        pw.print(prefix); pw.print("width: "); pw.println(mWidth);
-        pw.print(prefix); pw.print("height: "); pw.println(mHeight);
-        pw.print(prefix); pw.print("visible: "); pw.println(mIsShowing);
+    // When the window is touched outside, hide the window.
+    @Override
+    public boolean onTouch(View view, MotionEvent event) {
+        if (view == mContentView && event.getAction() == MotionEvent.ACTION_OUTSIDE) {
+            hide();
+            return true;
+        }
+        return false;
     }
 
-    /** FrameLayout that listens for touch events removes itself if the touch event is outside. */
-    private final class SelfRemovingView extends FrameLayout {
-        public SelfRemovingView(Context context) {
-            super(context);
+    private boolean updateHeight() {
+        final Rect displayBounds = mLastDisplayBounds;
+        if (displayBounds == null) {
+            return false;
         }
 
-        @Override
-        public boolean onTouchEvent(MotionEvent event) {
-            if (event.getAction() == MotionEvent.ACTION_OUTSIDE) {
-                hide();
-                return true;
-            } else {
-                return super.onTouchEvent(event);
+        mContentView.measure(
+                MeasureSpec.makeMeasureSpec(displayBounds.width(), MeasureSpec.AT_MOST),
+                MeasureSpec.makeMeasureSpec(displayBounds.height(), MeasureSpec.AT_MOST));
+        int height = mContentView.getMeasuredHeight();
+        if (height != mLastHeight) {
+            if (DEBUG) Slog.d(TAG, "update height=" + height);
+            mLastHeight = height;
+            update(height, mLastBounds, displayBounds);
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    private void updateBounds(Rect bounds) {
+        if (!bounds.equals(mLastBounds)) {
+            if (DEBUG) Slog.d(TAG, "update bounds=" + bounds);
+            mLastBounds = bounds;
+
+            update(mLastHeight, bounds, mLastDisplayBounds);
+        }
+    }
+
+    private void updateDisplayBounds(Rect displayBounds) {
+        if (!displayBounds.equals(mLastDisplayBounds)) {
+            if (DEBUG) Slog.d(TAG, "update displayBounds=" + displayBounds);
+            mLastDisplayBounds = displayBounds;
+
+            if (!updateHeight()) {
+                update(mLastHeight, mLastBounds, displayBounds);
             }
         }
     }
+
+    // Updates the window if height, bounds, and displayBounds are not null.
+    // Caller should ensure that something changed before calling.
+    private void update(int height, @Nullable Rect bounds, @Nullable Rect displayBounds) {
+        if (height == NULL_HEIGHT || bounds == null || displayBounds == null) {
+            return;
+        }
+
+        if (DEBUG) Slog.d(TAG, "update height=" + height + ", bounds=" + bounds
+                + ", displayBounds=" + displayBounds);
+
+        final LayoutParams params = createWindowLayoutParams(mAppToken,
+                LayoutParams.FLAG_NOT_TOUCH_MODAL // outside touches go to windows behind us
+                | LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH); // outside touches trigger MotionEvent
+        params.setTitle("AutoFill Fill"); // used for debugging
+        updatePosition(params, height, mMinMargin, bounds, displayBounds);
+        if (!mContentView.isAttachedToWindow()) {
+            if (DEBUG) Slog.d(TAG, "adding mContentView");
+            mWm.addView(mContentView, params);
+            mContentView.setOnTouchListener(this);
+        } else {
+            if (DEBUG) Slog.d(TAG, "updating mContentView");
+            mWm.updateViewLayout(mContentView, params);
+        }
+    }
+
+    /**
+     * Updates the position of the window by altering the {@link LayoutParams}.
+     *
+     * <p>The window can be anchored either above or below the bounds. Anchoring the window below
+     * the bounds is preferred, if it fits. Otherwise, anchor the window on the side with more
+     * space.
+     *
+     * @param params the params to update
+     * @param height the requested height of the window
+     * @param minMargin the minimum margin between the window and the display bounds
+     * @param bounds the region the window should be anchored to
+     * @param displayBounds the region in which the window may be displayed
+     */
+    private static void updatePosition(
+            LayoutParams params,
+            int height,
+            int minMargin,
+            Rect bounds,
+            Rect displayBounds) {
+        boolean below;
+        int verticalSpace;
+        final int verticalSpaceBelow = displayBounds.bottom - bounds.bottom - minMargin;
+        if (height <= verticalSpaceBelow) {
+            // Fits below bounds.
+            below = true;
+            verticalSpace = height;
+        } else {
+            final int verticalSpaceAbove = bounds.top - displayBounds.top - minMargin;
+            if (height <= verticalSpaceAbove) {
+                // Fits above bounds.
+                below = false;
+                verticalSpace = height;
+            } else {
+                // Pick above/below based on which has the most space.
+                if (verticalSpaceBelow >= verticalSpaceAbove) {
+                    below = true;
+                    verticalSpace = verticalSpaceBelow;
+                } else {
+                    below = false;
+                    verticalSpace = verticalSpaceAbove;
+                }
+            }
+        }
+
+        int gravity;
+        int y;
+        if (below) {
+            if (DEBUG) Slog.d(TAG, "anchorBelow");
+            gravity = Gravity.TOP | Gravity.LEFT;
+            y = bounds.bottom - displayBounds.top;
+        } else {
+            if (DEBUG) Slog.d(TAG, "anchorAbove");
+            gravity = Gravity.BOTTOM | Gravity.LEFT;
+            y = displayBounds.bottom - bounds.top;
+        }
+
+        final int x = bounds.left - displayBounds.left;
+
+        params.gravity = gravity;
+        params.x = x;
+        params.y = y;
+        params.width = bounds.width();
+        params.height = verticalSpace;
+    }
+
+    private static LayoutParams createWindowLayoutParams(IBinder appToken, int flags) {
+        final LayoutParams params = new LayoutParams();
+        params.token = appToken;
+        params.type = LayoutParams.TYPE_PHONE;
+        params.flags =
+                flags
+                | LayoutParams.FLAG_NOT_FOCUSABLE // don't receive input events
+                | LayoutParams.FLAG_ALT_FOCUSABLE_IM; // resize for soft input
+        params.format = PixelFormat.TRANSLUCENT;
+        return params;
+    }
 }
diff --git a/services/autofill/java/com/android/server/autofill/AutoFillManagerServiceImpl.java b/services/autofill/java/com/android/server/autofill/AutoFillManagerServiceImpl.java
index 55470d13be438..8c74532532e14 100644
--- a/services/autofill/java/com/android/server/autofill/AutoFillManagerServiceImpl.java
+++ b/services/autofill/java/com/android/server/autofill/AutoFillManagerServiceImpl.java
@@ -720,7 +720,9 @@ final class AutoFillManagerServiceImpl {
                     filterText = text.toString();
                 }
             }
-            getUiForShowing().showFillUi(viewState, response.getDatasets(), bounds, filterText);
+
+            getUiForShowing().showFillUi(mActivityToken, viewState, response.getDatasets(),
+                    bounds, filterText);
         }
 
         private void processResponseLocked(FillResponse response) {
diff --git a/services/autofill/java/com/android/server/autofill/AutoFillUI.java b/services/autofill/java/com/android/server/autofill/AutoFillUI.java
index c482c402e775a..e9fc0440ba3a9 100644
--- a/services/autofill/java/com/android/server/autofill/AutoFillUI.java
+++ b/services/autofill/java/com/android/server/autofill/AutoFillUI.java
@@ -17,6 +17,7 @@ package com.android.server.autofill;
 
 import static com.android.server.autofill.Helper.DEBUG;
 
+import android.annotation.Nullable;
 import android.app.Notification;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
@@ -71,8 +72,6 @@ final class AutoFillUI {
     private AnchoredWindow mFillWindow;
     private DatasetPicker mFillView;
     private ViewState mViewState;
-    private Rect mBounds;
-    private String mFilterText;
 
     private AutoFillUiCallback mCallback;
     private IBinder mActivityToken;
@@ -138,8 +137,6 @@ final class AutoFillUI {
         }
 
         mViewState = null;
-        mBounds = null;
-        mFilterText = null;
         mFillView = null;
         mFillWindow = null;
     }
@@ -147,17 +144,23 @@ final class AutoFillUI {
     /**
      * Shows the fill UI, removing the previous fill UI if the has changed.
      *
+     * @param appToken the token of the app to be autofilled
      * @param viewState the view state, compared by reference to know if new UI should be shown
      * @param datasets the datasets to show, not used if viewState is the same
      * @param bounds bounds of the view to be filled, used if changed
      * @param filterText text of the view to be filled, used if changed
      */
-    void showFillUi(ViewState viewState, ArraySet<Dataset> datasets, Rect bounds,
-            String filterText) {
+    void showFillUi(IBinder appToken, ViewState viewState, @Nullable ArraySet<Dataset> datasets,
+            Rect bounds, String filterText) {
         if (!hasCallback()) {
             return;
         }
 
+        UiThread.getHandler().runWithScissors(() -> {
+            hideSnackbarUiThread();
+            hideFillResponseAuthUiUiThread();
+        }, 0);
+
         if (datasets == null) {
             // TODO(b/33197203): shouldn't be called, but keeping the WTF for a while just to be
             // safe, otherwise it would crash system server...
@@ -165,13 +168,10 @@ final class AutoFillUI {
             return;
         }
 
-        // TODO(b/33197203): call to hideAll() was making it janky because then mViewState is set
-        // to null and hence the first check inside the lambada fails, causing it to be displayed
-        // twice in some cases.
-        hideAll();
-
         UiThread.getHandler().runWithScissors(() -> {
             if (mViewState == null || !mViewState.mId.equals(viewState.mId)) {
+                hideFillUiUiThread();
+
                 mViewState = viewState;
 
                 mFillView = new DatasetPicker(mContext, datasets,
@@ -183,25 +183,15 @@ final class AutoFillUI {
                             callback.fill(dataset);
                             hideFillUi();
                         });
-                // TODO(b/33197203): No magical numbers
-                mFillWindow = new AnchoredWindow(
-                        mWm, mFillView, 800, ViewGroup.LayoutParams.WRAP_CONTENT);
 
-                if (DEBUG) Slog.d(TAG, "show FillUi: " + viewState.mId);
+                mFillWindow = new AnchoredWindow(mWm, appToken, mFillView);
+
+                if (DEBUG) Slog.d(TAG, "showFillUi(): view changed");
             }
 
-            // TODO(b/33197203): If bounds are the same we would not show, fix this
-            if (!bounds.equals(mBounds)) {
-                if (DEBUG) Slog.d(TAG, "update FillUi bounds: " + mBounds);
-                mBounds = bounds;
-                mFillWindow.show(mBounds);
-            }
-
-            if (!filterText.equals(mFilterText)) {
-                if (DEBUG) Slog.d(TAG, "update FillUi filter text: " + mFilterText);
-                mFilterText = filterText;
-                mFillView.update(mFilterText);
-            }
+            if (DEBUG) Slog.d(TAG, "showFillUi(): bounds=" + bounds + ", filterText=" + filterText);
+            mFillView.update(filterText);
+            mFillWindow.show(bounds);
         }, 0);
     }
 
@@ -268,8 +258,6 @@ final class AutoFillUI {
         pw.print(prefix); pw.print("mActivityToken: "); pw.println(mActivityToken);
         pw.print(prefix); pw.print("mSnackBar: "); pw.println(mSnackbar);
         pw.print(prefix); pw.print("mViewState: "); pw.println(mViewState);
-        pw.print(prefix); pw.print("mBounds: "); pw.println(mBounds);
-        pw.print(prefix); pw.print("mFilterText: "); pw.println(mFilterText);
     }
 
     //similar to a snackbar, but can be a bit custom since it is more than just text. This will