Merge "Allow drag-n-drop to auto-scroll when near top/bottom of dirlist." into nyc-andromeda-dev (31d9b44b) · Commits · e / os / android_packages_apps_DocumentsUI

res/values/dimens.xml

+2 −0

Original line number	Diff line number	Diff line
		@@ -46,4 +46,6 @@
		<dimen name="drag_shadow_width">160dp</dimen>
		<dimen name="drag_shadow_height">48dp</dimen>

		<dimen name="autoscroll_edge_height">32dp</dimen>

		</resources>

src/com/android/documentsui/Shared.java

+0 −5

Original line number	Diff line number	Diff line
		@@ -21,7 +21,6 @@ import android.app.AlertDialog;
		import android.content.Context;
		import android.content.Intent;
		import android.content.res.Configuration;
		import android.net.Uri;
		import android.os.Looper;
		import android.provider.DocumentsContract;
		import android.text.TextUtils;
		@@ -30,10 +29,6 @@ import android.text.format.Time;
		import android.util.Log;
		import android.view.WindowManager;

		import com.android.documentsui.model.DocumentInfo;
		import com.android.documentsui.model.RootInfo;

		import java.io.FileNotFoundException;
		import java.text.Collator;
		import java.util.ArrayList;
		import java.util.List;

src/com/android/documentsui/dirlist/BandController.java

+29 −120

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@ package com.android.documentsui.dirlist;
		import static com.android.documentsui.Shared.DEBUG;
		import static com.android.documentsui.dirlist.ModelBackedDocumentsAdapter.ITEM_TYPE_DIRECTORY;
		import static com.android.documentsui.dirlist.ModelBackedDocumentsAdapter.ITEM_TYPE_DOCUMENT;
		import static com.android.documentsui.dirlist.ViewAutoScroller.NOT_SET;

		import android.graphics.Point;
		import android.graphics.Rect;
		@@ -39,6 +40,8 @@ import com.android.documentsui.Events.InputEvent;
		import com.android.documentsui.Events.MotionInputEvent;
		import com.android.documentsui.R;
		import com.android.documentsui.dirlist.MultiSelectManager.Selection;
		import com.android.documentsui.dirlist.ViewAutoScroller.ScrollActionDelegate;
		import com.android.documentsui.dirlist.ViewAutoScroller.ScrollDistanceDelegate;

		import java.util.ArrayList;
		import java.util.Collections;
		@@ -54,15 +57,14 @@ import java.util.Set;
		*/
		public class BandController extends RecyclerView.OnScrollListener {

		private static final int NOT_SET = -1;

		private static final String TAG = "BandController";
		private static final int AUTOSCROLL_EDGE_HEIGHT = 1;

		private final Runnable mModelBuilder;
		private final SelectionEnvironment mEnvironment;
		private final DocumentsAdapter mAdapter;
		private final MultiSelectManager mSelectionManager;
		private final Runnable mViewScroller = new ViewScroller();
		private final Runnable mViewScroller;
		private final GridModel.OnSelectionChangedListener mGridListener;

		@Nullable private Rect mBounds;
		@@ -70,9 +72,6 @@ public class BandController extends RecyclerView.OnScrollListener {
		@Nullable private Point mOrigin;
		@Nullable private BandController.GridModel mModel;

		// The time at which the current band selection-induced scroll began. If no scroll is in
		// progress, the value is NOT_SET.
		private long mScrollStartTime = NOT_SET;
		private Selection mSelection;

		public BandController(
		@@ -114,6 +113,25 @@ public class BandController extends RecyclerView.OnScrollListener {
		mSelectionManager = selectionManager;

		mEnvironment.addOnScrollListener(this);
		mViewScroller = new ViewAutoScroller(
		AUTOSCROLL_EDGE_HEIGHT,
		new ScrollDistanceDelegate() {
		@Override
		public Point getCurrentPosition() {
		return mCurrentPosition;
		}

		@Override
		public int getViewHeight() {
		return mEnvironment.getHeight();
		}

		@Override
		public boolean isActive() {
		return BandController.this.isActive();
		}
		},
		env);

		mAdapter.registerAdapterDataObserver(
		new RecyclerView.AdapterDataObserver() {
		@@ -173,6 +191,10 @@ public class BandController extends RecyclerView.OnScrollListener {
		};
		}

		private boolean isActive() {
		return mModel != null;
		}

		void bindSelection(Selection selection) {
		mSelection = selection;
		}
		@@ -212,10 +234,6 @@ public class BandController extends RecyclerView.OnScrollListener {
		return isActive();
		}

		private boolean isActive() {
		return mModel != null;
		}

		/**
		* Handle a change in layout by cleaning up and getting rid of the old model and creating
		* a new model which will track the new layout.
		@@ -336,112 +354,6 @@ public class BandController extends RecyclerView.OnScrollListener {
		return mSelectionManager.notifyBeforeItemStateChange(id, nextState);
		}

		private class ViewScroller implements Runnable {
		/**
		* The number of milliseconds of scrolling at which scroll speed continues to increase.
		* At first, the scroll starts slowly; then, the rate of scrolling increases until it
		* reaches its maximum value at after this many milliseconds.
		*/
		private static final long SCROLL_ACCELERATION_LIMIT_TIME_MS = 2000;

		@Override
		public void run() {
		// Compute the number of pixels the pointer's y-coordinate is past the view.
		// Negative values mean the pointer is at or before the top of the view, and
		// positive values mean that the pointer is at or after the bottom of the view. Note
		// that one additional pixel is added here so that the view still scrolls when the
		// pointer is exactly at the top or bottom.
		int pixelsPastView = 0;
		if (mCurrentPosition.y <= 0) {
		pixelsPastView = mCurrentPosition.y - 1;
		} else if (mCurrentPosition.y >= mEnvironment.getHeight() - 1) {
		pixelsPastView = mCurrentPosition.y - mEnvironment.getHeight() + 1;
		}

		if (!isActive() \|\| pixelsPastView == 0) {
		// If band selection is inactive, or if it is active but not at the edge of the
		// view, no scrolling is necessary.
		mScrollStartTime = NOT_SET;
		return;
		}

		if (mScrollStartTime == NOT_SET) {
		// If the pointer was previously not at the edge of the view but now is, set the
		// start time for the scroll.
		mScrollStartTime = System.currentTimeMillis();
		}

		// Compute the number of pixels to scroll, and scroll that many pixels.
		final int numPixels = computeScrollDistance(
		pixelsPastView, System.currentTimeMillis() - mScrollStartTime);
		mEnvironment.scrollBy(numPixels);

		mEnvironment.removeCallback(mViewScroller);
		mEnvironment.runAtNextFrame(this);
		}

		/**
		* Computes the number of pixels to scroll based on how far the pointer is past the end
		* of the view and how long it has been there. Roughly based on ItemTouchHelper's
		* algorithm for computing the number of pixels to scroll when an item is dragged to the
		* end of a {@link RecyclerView}.
		* @param pixelsPastView
		* @param scrollDuration
		* @return
		*/
		private int computeScrollDistance(int pixelsPastView, long scrollDuration) {
		final int maxScrollStep = mEnvironment.getHeight();
		final int direction = (int) Math.signum(pixelsPastView);
		final int absPastView = Math.abs(pixelsPastView);

		// Calculate the ratio of how far out of the view the pointer currently resides to
		// the entire height of the view.
		final float outOfBoundsRatio = Math.min(
		1.0f, (float) absPastView / mEnvironment.getHeight());
		// Interpolate this ratio and use it to compute the maximum scroll that should be
		// possible for this step.
		final float cappedScrollStep =
		direction * maxScrollStep * smoothOutOfBoundsRatio(outOfBoundsRatio);

		// Likewise, calculate the ratio of the time spent in the scroll to the limit.
		final float timeRatio = Math.min(
		1.0f, (float) scrollDuration / SCROLL_ACCELERATION_LIMIT_TIME_MS);
		// Interpolate this ratio and use it to compute the final number of pixels to
		// scroll.
		final int numPixels = (int) (cappedScrollStep * smoothTimeRatio(timeRatio));

		// If the final number of pixels to scroll ends up being 0, the view should still
		// scroll at least one pixel.
		return numPixels != 0 ? numPixels : direction;
		}

		/**
		* Interpolates the given out of bounds ratio on a curve which starts at (0,0) and ends
		* at (1,1) and quickly approaches 1 near the start of that interval. This ensures that
		* drags that are at the edge or barely past the edge of the view still cause sufficient
		* scrolling. The equation y=(x-1)^5+1 is used, but this could also be tweaked if
		* needed.
		* @param ratio A ratio which is in the range [0, 1].
		* @return A "smoothed" value, also in the range [0, 1].
		*/
		private float smoothOutOfBoundsRatio(float ratio) {
		return (float) Math.pow(ratio - 1.0f, 5) + 1.0f;
		}

		/**
		* Interpolates the given time ratio on a curve which starts at (0,0) and ends at (1,1)
		* and stays close to 0 for most input values except those very close to 1. This ensures
		* that scrolls start out very slowly but speed up drastically after the scroll has been
		* in progress close to SCROLL_ACCELERATION_LIMIT_TIME_MS. The equation y=x^5 is used,
		* but this could also be tweaked if needed.
		* @param ratio A ratio which is in the range [0, 1].
		* @return A "smoothed" value, also in the range [0, 1].
		*/
		private float smoothTimeRatio(float ratio) {
		return (float) Math.pow(ratio, 5);
		}
		};

		@Override
		public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
		if (!isActive()) {
		@@ -1110,16 +1022,13 @@ public class BandController extends RecyclerView.OnScrollListener {
		* Provides functionality for BandController. Exists primarily to tests that are
		* fully isolated from RecyclerView.
		*/
		interface SelectionEnvironment {
		interface SelectionEnvironment extends ScrollActionDelegate {
		void showBand(Rect rect);
		void hideBand();
		void addOnScrollListener(RecyclerView.OnScrollListener listener);
		void removeOnScrollListener(RecyclerView.OnScrollListener listener);
		void scrollBy(int dy);
		int getHeight();
		void invalidateView();
		void runAtNextFrame(Runnable r);
		void removeCallback(Runnable r);
		Point createAbsolutePoint(Point relativePoint);
		Rect getAbsoluteRectForChildViewAt(int index);
		int getAdapterPositionAt(int index);

src/com/android/documentsui/dirlist/DirectoryFragment.java

+4 −3

Original line number	Diff line number	Diff line
		@@ -74,7 +74,6 @@ import android.widget.Toolbar;
		import com.android.documentsui.BaseActivity;
		import com.android.documentsui.DirectoryLoader;
		import com.android.documentsui.DirectoryResult;
		import com.android.documentsui.clipping.DocumentClipper;
		import com.android.documentsui.DocumentsActivity;
		import com.android.documentsui.DocumentsApplication;
		import com.android.documentsui.Events.InputEvent;
		@@ -93,6 +92,7 @@ import com.android.documentsui.Shared;
		import com.android.documentsui.Snackbars;
		import com.android.documentsui.State;
		import com.android.documentsui.State.ViewMode;
		import com.android.documentsui.clipping.DocumentClipper;
		import com.android.documentsui.clipping.UrisSupplier;
		import com.android.documentsui.dirlist.MultiSelectManager.Selection;
		import com.android.documentsui.dirlist.UserInputHandler.DocumentDetails;
		@@ -183,7 +183,7 @@ public class DirectoryFragment extends Fragment
		private @Nullable BandController mBandController;
		private @Nullable ActionMode mActionMode;

		private DirectoryDragListener mOnDragListener;
		private DragScrollListener mOnDragListener;
		private MenuManager mMenuManager;

		@Override
		@@ -210,7 +210,8 @@ public class DirectoryFragment extends Fragment

		mRecView.setItemAnimator(new DirectoryItemAnimator(getActivity()));

		mOnDragListener = new DirectoryDragListener(this);
		mOnDragListener = DragScrollListener.create(
		getActivity(), new DirectoryDragListener(this), mRecView);

		// Make the recycler and the empty views responsive to drop events.
		mRecView.setOnDragListener(mOnDragListener);

src/com/android/documentsui/dirlist/DragScrollListener.java

0 → 100644

+167 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2016 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package com.android.documentsui.dirlist;

		import android.content.Context;
		import android.graphics.Point;
		import android.view.DragEvent;
		import android.view.View;
		import android.view.View.OnDragListener;

		import com.android.documentsui.ItemDragListener;
		import com.android.documentsui.ItemDragListener.DragHost;
		import com.android.documentsui.dirlist.ViewAutoScroller.ScrollActionDelegate;
		import com.android.documentsui.dirlist.ViewAutoScroller.ScrollDistanceDelegate;
		import com.android.documentsui.R;

		import java.util.function.BooleanSupplier;
		import java.util.function.IntSupplier;

		import javax.annotation.Nullable;

		/**
		* This class acts as a middle-man handler for potential auto-scrolling before passing the dragEvent
		* onto {@link DirectoryDragListener}.
		*/
		class DragScrollListener implements OnDragListener {

		private final ItemDragListener<? extends DragHost> mDragHandler;
		private final IntSupplier mHeight;
		private final BooleanSupplier mCanScrollUp;
		private final BooleanSupplier mCanScrollDown;
		private final int mAutoScrollEdgeHeight;
		private final Runnable mDragScroller;

		private boolean mDragHappening;
		private @Nullable Point mCurrentPosition;

		private DragScrollListener(
		Context context,
		ItemDragListener<? extends DragHost> dragHandler,
		IntSupplier heightSupplier,
		BooleanSupplier scrollUpSupplier,
		BooleanSupplier scrollDownSupplier,
		ViewAutoScroller.ScrollActionDelegate actionDelegate) {
		mDragHandler = dragHandler;
		mAutoScrollEdgeHeight = (int) context.getResources()
		.getDimension(R.dimen.autoscroll_edge_height);
		mHeight = heightSupplier;
		mCanScrollUp = scrollUpSupplier;
		mCanScrollDown = scrollDownSupplier;

		ScrollDistanceDelegate distanceDelegate = new ScrollDistanceDelegate() {
		@Override
		public Point getCurrentPosition() {
		return mCurrentPosition;
		}

		@Override
		public int getViewHeight() {
		return mHeight.getAsInt();
		}

		@Override
		public boolean isActive() {
		return mDragHappening;
		}
		};

		mDragScroller = new ViewAutoScroller(
		mAutoScrollEdgeHeight, distanceDelegate, actionDelegate);
		}

		static DragScrollListener create(
		Context context, ItemDragListener<? extends DragHost> dragHandler, View scrollView) {
		ScrollActionDelegate actionDelegate = new ScrollActionDelegate() {
		@Override
		public void scrollBy(int dy) {
		scrollView.scrollBy(0, dy);
		}

		@Override
		public void runAtNextFrame(Runnable r) {
		scrollView.postOnAnimation(r);

		}

		@Override
		public void removeCallback(Runnable r) {
		scrollView.removeCallbacks(r);
		}
		};
		DragScrollListener listener = new DragScrollListener(
		context,
		dragHandler,
		scrollView::getHeight,
		() -> {
		return scrollView.canScrollVertically(-1);
		},
		() -> {
		return scrollView.canScrollVertically(1);
		},
		actionDelegate);
		return listener;
		}

		@Override
		public boolean onDrag(View v, DragEvent event) {
		boolean handled = false;
		switch (event.getAction()) {
		case DragEvent.ACTION_DRAG_STARTED:
		mDragHappening = true;
		break;
		case DragEvent.ACTION_DRAG_ENDED:
		mDragHappening = false;
		break;
		case DragEvent.ACTION_DRAG_ENTERED:
		handled = insideDragZone();
		break;
		case DragEvent.ACTION_DRAG_LOCATION:
		handled = handleLocationEvent(v, event.getX(), event.getY());
		break;
		default:
		break;
		}

		if (!handled) {
		handled = mDragHandler.onDrag(v, event);
		}

		return handled;
		}

		private boolean handleLocationEvent(View v, float x, float y) {
		mCurrentPosition = new Point(Math.round(v.getX() + x), Math.round(v.getY() + y));
		if (insideDragZone()) {
		mDragScroller.run();
		return true;
		}
		return false;
		}

		private boolean insideDragZone() {
		if (mCurrentPosition == null) {
		return false;
		}

		boolean shouldScrollUp = mCurrentPosition.y < mAutoScrollEdgeHeight
		&& mCanScrollUp.getAsBoolean();
		boolean shouldScrollDown = mCurrentPosition.y > mHeight.getAsInt() - mAutoScrollEdgeHeight
		&& mCanScrollDown.getAsBoolean();
		return shouldScrollUp \|\| shouldScrollDown;
		}
		}
		No newline at end of file