mobile/android/base/ScrollAnimator.java@b8a032363ba2 (annotated)
mobile/android/base/ScrollAnimator.java
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
| michael@0 | 1 | /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*- |
| michael@0 | 2 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this file, |
| michael@0 | 4 | * You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | package org.mozilla.gecko; |
| michael@0 | 7 | |
| michael@0 | 8 | import java.util.Timer; |
| michael@0 | 9 | import java.util.TimerTask; |
| michael@0 | 10 | |
| michael@0 | 11 | import org.mozilla.gecko.util.GamepadUtils; |
| michael@0 | 12 | |
| michael@0 | 13 | import android.view.InputDevice; |
| michael@0 | 14 | import android.view.MotionEvent; |
| michael@0 | 15 | import android.view.View; |
| michael@0 | 16 | |
| michael@0 | 17 | public class ScrollAnimator implements View.OnGenericMotionListener { |
| michael@0 | 18 | private Timer mScrollTimer; |
| michael@0 | 19 | private int mX; |
| michael@0 | 20 | private int mY; |
| michael@0 | 21 | |
| michael@0 | 22 | // Assuming 60fps, this will make the view scroll once per frame |
| michael@0 | 23 | static final long MS_PER_FRAME = 1000 / 60; |
| michael@0 | 24 | |
| michael@0 | 25 | // Maximum number of pixels that can be scrolled per frame |
| michael@0 | 26 | static final float MAX_SCROLL = 0.075f * GeckoAppShell.getDpi(); |
| michael@0 | 27 | |
| michael@0 | 28 | private class ScrollRunnable extends TimerTask { |
| michael@0 | 29 | private View mView; |
| michael@0 | 30 | |
| michael@0 | 31 | public ScrollRunnable(View view) { |
| michael@0 | 32 | mView = view; |
| michael@0 | 33 | } |
| michael@0 | 34 | |
| michael@0 | 35 | @Override |
| michael@0 | 36 | public final void run() { |
| michael@0 | 37 | mView.scrollBy(mX, mY); |
| michael@0 | 38 | } |
| michael@0 | 39 | } |
| michael@0 | 40 | |
| michael@0 | 41 | @Override |
| michael@0 | 42 | public boolean onGenericMotion(View view, MotionEvent event) { |
| michael@0 | 43 | if ((event.getSource() & InputDevice.SOURCE_CLASS_JOYSTICK) != 0) { |
| michael@0 | 44 | switch (event.getAction()) { |
| michael@0 | 45 | case MotionEvent.ACTION_MOVE: |
| michael@0 | 46 | // Cancel the animation if the joystick is in a neutral position |
| michael@0 | 47 | if (GamepadUtils.isValueInDeadZone(event, MotionEvent.AXIS_X) && |
| michael@0 | 48 | GamepadUtils.isValueInDeadZone(event, MotionEvent.AXIS_Y)) { |
| michael@0 | 49 | if (mScrollTimer != null) { |
| michael@0 | 50 | mScrollTimer.cancel(); |
| michael@0 | 51 | mScrollTimer = null; |
| michael@0 | 52 | } |
| michael@0 | 53 | return true; |
| michael@0 | 54 | } |
| michael@0 | 55 | |
| michael@0 | 56 | // Scroll with a velocity relative to the screen DPI |
| michael@0 | 57 | mX = (int) (event.getAxisValue(MotionEvent.AXIS_X) * MAX_SCROLL); |
| michael@0 | 58 | mY = (int) (event.getAxisValue(MotionEvent.AXIS_Y) * MAX_SCROLL); |
| michael@0 | 59 | |
| michael@0 | 60 | // Start the timer; the view will continue to scroll as long as |
| michael@0 | 61 | // the joystick is not in the deadzone. |
| michael@0 | 62 | if (mScrollTimer == null) { |
| michael@0 | 63 | mScrollTimer = new Timer(); |
| michael@0 | 64 | ScrollRunnable task = new ScrollRunnable(view); |
| michael@0 | 65 | mScrollTimer.scheduleAtFixedRate(task, 0, MS_PER_FRAME); |
| michael@0 | 66 | } |
| michael@0 | 67 | |
| michael@0 | 68 | return true; |
| michael@0 | 69 | } |
| michael@0 | 70 | } |
| michael@0 | 71 | |
| michael@0 | 72 | return false; |
| michael@0 | 73 | } |
| michael@0 | 74 | |
| michael@0 | 75 | /** |
| michael@0 | 76 | * Cancels the running scroll animation if it is in progress. |
| michael@0 | 77 | */ |
| michael@0 | 78 | public void cancel() { |
| michael@0 | 79 | if (mScrollTimer != null) { |
| michael@0 | 80 | mScrollTimer.cancel(); |
| michael@0 | 81 | mScrollTimer = null; |
| michael@0 | 82 | } |
| michael@0 | 83 | } |
| michael@0 | 84 | } |
