1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.gallery3d.ui;
18 
19 import android.content.Context;
20 import android.view.MotionEvent;
21 
22 import com.android.gallery3d.R;
23 import com.android.gallery3d.common.Utils;
24 import com.android.gallery3d.glrenderer.GLCanvas;
25 import com.android.gallery3d.glrenderer.NinePatchTexture;
26 import com.android.gallery3d.glrenderer.ResourceTexture;
27 import com.android.gallery3d.glrenderer.StringTexture;
28 import com.android.gallery3d.util.GalleryUtils;
29 
30 public class UndoBarView extends GLView {
31     @SuppressWarnings("unused")
32     private static final String TAG = "UndoBarView";
33 
34     private static final int WHITE = 0xFFFFFFFF;
35     private static final int GRAY = 0xFFAAAAAA;
36 
37     private final NinePatchTexture mPanel;
38     private final StringTexture mUndoText;
39     private final StringTexture mDeletedText;
40     private final ResourceTexture mUndoIcon;
41     private final int mBarHeight;
42     private final int mBarMargin;
43     private final int mUndoTextMargin;
44     private final int mIconSize;
45     private final int mIconMargin;
46     private final int mSeparatorTopMargin;
47     private final int mSeparatorBottomMargin;
48     private final int mSeparatorRightMargin;
49     private final int mSeparatorWidth;
50     private final int mDeletedTextMargin;
51     private final int mClickRegion;
52 
53     private OnClickListener mOnClickListener;
54     private boolean mDownOnButton;
55 
56     // This is the layout of UndoBarView. The unit is dp.
57     //
58     //    +-+----+----------------+-+--+----+-+------+--+-+
59     // 48 | |    | Deleted        | |  | <- | | UNDO |  | |
60     //    +-+----+----------------+-+--+----+-+------+--+-+
61     //     4  16                   1 12  32  8        16 4
UndoBarView(Context context)62     public UndoBarView(Context context) {
63         mBarHeight = GalleryUtils.dpToPixel(48);
64         mBarMargin = GalleryUtils.dpToPixel(4);
65         mUndoTextMargin = GalleryUtils.dpToPixel(16);
66         mIconMargin = GalleryUtils.dpToPixel(8);
67         mIconSize = GalleryUtils.dpToPixel(32);
68         mSeparatorRightMargin = GalleryUtils.dpToPixel(12);
69         mSeparatorTopMargin = GalleryUtils.dpToPixel(10);
70         mSeparatorBottomMargin = GalleryUtils.dpToPixel(10);
71         mSeparatorWidth = GalleryUtils.dpToPixel(1);
72         mDeletedTextMargin = GalleryUtils.dpToPixel(16);
73 
74         mPanel = new NinePatchTexture(context, R.drawable.panel_undo_holo);
75         mUndoText = StringTexture.newInstance(context.getString(R.string.undo),
76                 GalleryUtils.dpToPixel(12), GRAY, 0, true);
77         mDeletedText = StringTexture.newInstance(
78                 context.getString(R.string.deleted),
79                 GalleryUtils.dpToPixel(16), WHITE);
80         mUndoIcon = new ResourceTexture(
81                 context, R.drawable.ic_menu_revert_holo_dark);
82         mClickRegion = mBarMargin + mUndoTextMargin + mUndoText.getWidth()
83                 + mIconMargin + mIconSize + mSeparatorRightMargin;
84     }
85 
setOnClickListener(OnClickListener listener)86     public void setOnClickListener(OnClickListener listener) {
87         mOnClickListener = listener;
88     }
89 
90     @Override
onMeasure(int widthSpec, int heightSpec)91     protected void onMeasure(int widthSpec, int heightSpec) {
92         setMeasuredSize(0 /* unused */, mBarHeight);
93     }
94 
95     @Override
render(GLCanvas canvas)96     protected void render(GLCanvas canvas) {
97         super.render(canvas);
98         advanceAnimation();
99 
100         canvas.save(GLCanvas.SAVE_FLAG_ALPHA);
101         canvas.multiplyAlpha(mAlpha);
102 
103         int w = getWidth();
104         int h = getHeight();
105         mPanel.draw(canvas, mBarMargin, 0, w - mBarMargin * 2, mBarHeight);
106 
107         int x = w - mBarMargin;
108         int y;
109 
110         x -= mUndoTextMargin + mUndoText.getWidth();
111         y = (mBarHeight - mUndoText.getHeight()) / 2;
112         mUndoText.draw(canvas, x, y);
113 
114         x -= mIconMargin + mIconSize;
115         y = (mBarHeight - mIconSize) / 2;
116         mUndoIcon.draw(canvas, x, y, mIconSize, mIconSize);
117 
118         x -= mSeparatorRightMargin + mSeparatorWidth;
119         y = mSeparatorTopMargin;
120         canvas.fillRect(x, y, mSeparatorWidth,
121                 mBarHeight - mSeparatorTopMargin - mSeparatorBottomMargin, GRAY);
122 
123         x = mBarMargin + mDeletedTextMargin;
124         y = (mBarHeight - mDeletedText.getHeight()) / 2;
125         mDeletedText.draw(canvas, x, y);
126 
127         canvas.restore();
128     }
129 
130     @Override
onTouch(MotionEvent event)131     protected boolean onTouch(MotionEvent event) {
132         switch (event.getAction()) {
133             case MotionEvent.ACTION_DOWN:
134                 mDownOnButton = inUndoButton(event);
135                 break;
136             case MotionEvent.ACTION_UP:
137                 if (mDownOnButton) {
138                     if (mOnClickListener != null && inUndoButton(event)) {
139                         mOnClickListener.onClick(this);
140                     }
141                     mDownOnButton = false;
142                 }
143                 break;
144             case MotionEvent.ACTION_CANCEL:
145                 mDownOnButton = false;
146                 break;
147         }
148         return true;
149     }
150 
151     // Check if the event is on the right of the separator
inUndoButton(MotionEvent event)152     private boolean inUndoButton(MotionEvent event) {
153         float x = event.getX();
154         float y = event.getY();
155         int w = getWidth();
156         int h = getHeight();
157         return (x >= w - mClickRegion && x < w && y >= 0 && y < h);
158     }
159 
160     ////////////////////////////////////////////////////////////////////////////
161     //  Alpha Animation
162     ////////////////////////////////////////////////////////////////////////////
163 
164     private static final long NO_ANIMATION = -1;
165     private static long ANIM_TIME = 200;
166     private long mAnimationStartTime = NO_ANIMATION;
167     private float mFromAlpha, mToAlpha;
168     private float mAlpha;
169 
getTargetAlpha(int visibility)170     private static float getTargetAlpha(int visibility) {
171         return (visibility == VISIBLE) ? 1f : 0f;
172     }
173 
174     @Override
setVisibility(int visibility)175     public void setVisibility(int visibility) {
176         mAlpha = getTargetAlpha(visibility);
177         mAnimationStartTime = NO_ANIMATION;
178         super.setVisibility(visibility);
179         invalidate();
180     }
181 
animateVisibility(int visibility)182     public void animateVisibility(int visibility) {
183         float target = getTargetAlpha(visibility);
184         if (mAnimationStartTime == NO_ANIMATION && mAlpha == target) return;
185         if (mAnimationStartTime != NO_ANIMATION && mToAlpha == target) return;
186 
187         mFromAlpha = mAlpha;
188         mToAlpha = target;
189         mAnimationStartTime = AnimationTime.startTime();
190 
191         super.setVisibility(VISIBLE);
192         invalidate();
193     }
194 
advanceAnimation()195     private void advanceAnimation() {
196         if (mAnimationStartTime == NO_ANIMATION) return;
197 
198         float delta = (float) (AnimationTime.get() - mAnimationStartTime) /
199                 ANIM_TIME;
200         mAlpha = mFromAlpha + ((mToAlpha > mFromAlpha) ? delta : -delta);
201         mAlpha = Utils.clamp(mAlpha, 0f, 1f);
202 
203         if (mAlpha == mToAlpha) {
204             mAnimationStartTime = NO_ANIMATION;
205             if (mAlpha == 0) {
206                 super.setVisibility(INVISIBLE);
207             }
208         }
209         invalidate();
210     }
211 }
212