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      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.util.GalleryUtils;
     25 
     26 public class UndoBarView extends GLView {
     27     @SuppressWarnings("unused")
     28     private static final String TAG = "UndoBarView";
     29 
     30     private static final int WHITE = 0xFFFFFFFF;
     31     private static final int GRAY = 0xFFAAAAAA;
     32 
     33     private final NinePatchTexture mPanel;
     34     private final StringTexture mUndoText;
     35     private final StringTexture mDeletedText;
     36     private final ResourceTexture mUndoIcon;
     37     private final int mBarHeight;
     38     private final int mBarMargin;
     39     private final int mUndoTextMargin;
     40     private final int mIconSize;
     41     private final int mIconMargin;
     42     private final int mSeparatorTopMargin;
     43     private final int mSeparatorBottomMargin;
     44     private final int mSeparatorRightMargin;
     45     private final int mSeparatorWidth;
     46     private final int mDeletedTextMargin;
     47     private final int mClickRegion;
     48 
     49     private OnClickListener mOnClickListener;
     50     private boolean mDownOnButton;
     51 
     52     // This is the layout of UndoBarView. The unit is dp.
     53     //
     54     //    +-+----+----------------+-+--+----+-+------+--+-+
     55     // 48 | |    | Deleted        | |  | <- | | UNDO |  | |
     56     //    +-+----+----------------+-+--+----+-+------+--+-+
     57     //     4  16                   1 12  32  8        16 4
     58     public UndoBarView(Context context) {
     59         mBarHeight = GalleryUtils.dpToPixel(48);
     60         mBarMargin = GalleryUtils.dpToPixel(4);
     61         mUndoTextMargin = GalleryUtils.dpToPixel(16);
     62         mIconMargin = GalleryUtils.dpToPixel(8);
     63         mIconSize = GalleryUtils.dpToPixel(32);
     64         mSeparatorRightMargin = GalleryUtils.dpToPixel(12);
     65         mSeparatorTopMargin = GalleryUtils.dpToPixel(10);
     66         mSeparatorBottomMargin = GalleryUtils.dpToPixel(10);
     67         mSeparatorWidth = GalleryUtils.dpToPixel(1);
     68         mDeletedTextMargin = GalleryUtils.dpToPixel(16);
     69 
     70         mPanel = new NinePatchTexture(context, R.drawable.panel_undo_holo);
     71         mUndoText = StringTexture.newInstance(context.getString(R.string.undo),
     72                 GalleryUtils.dpToPixel(12), GRAY, 0, true);
     73         mDeletedText = StringTexture.newInstance(
     74                 context.getString(R.string.deleted),
     75                 GalleryUtils.dpToPixel(16), WHITE);
     76         mUndoIcon = new ResourceTexture(
     77                 context, R.drawable.ic_menu_revert_holo_dark);
     78         mClickRegion = mBarMargin + mUndoTextMargin + mUndoText.getWidth()
     79                 + mIconMargin + mIconSize + mSeparatorRightMargin;
     80     }
     81 
     82     public void setOnClickListener(OnClickListener listener) {
     83         mOnClickListener = listener;
     84     }
     85 
     86     @Override
     87     protected void onMeasure(int widthSpec, int heightSpec) {
     88         setMeasuredSize(0 /* unused */, mBarHeight);
     89     }
     90 
     91     @Override
     92     protected void render(GLCanvas canvas) {
     93         super.render(canvas);
     94         advanceAnimation();
     95 
     96         canvas.save(GLCanvas.SAVE_FLAG_ALPHA);
     97         canvas.multiplyAlpha(mAlpha);
     98 
     99         int w = getWidth();
    100         int h = getHeight();
    101         mPanel.draw(canvas, mBarMargin, 0, w - mBarMargin * 2, mBarHeight);
    102 
    103         int x = w - mBarMargin;
    104         int y;
    105 
    106         x -= mUndoTextMargin + mUndoText.getWidth();
    107         y = (mBarHeight - mUndoText.getHeight()) / 2;
    108         mUndoText.draw(canvas, x, y);
    109 
    110         x -= mIconMargin + mIconSize;
    111         y = (mBarHeight - mIconSize) / 2;
    112         mUndoIcon.draw(canvas, x, y, mIconSize, mIconSize);
    113 
    114         x -= mSeparatorRightMargin + mSeparatorWidth;
    115         y = mSeparatorTopMargin;
    116         canvas.fillRect(x, y, mSeparatorWidth,
    117                 mBarHeight - mSeparatorTopMargin - mSeparatorBottomMargin, GRAY);
    118 
    119         x = mBarMargin + mDeletedTextMargin;
    120         y = (mBarHeight - mDeletedText.getHeight()) / 2;
    121         mDeletedText.draw(canvas, x, y);
    122 
    123         canvas.restore();
    124     }
    125 
    126     @Override
    127     protected boolean onTouch(MotionEvent event) {
    128         switch (event.getAction()) {
    129             case MotionEvent.ACTION_DOWN:
    130                 mDownOnButton = inUndoButton(event);
    131                 break;
    132             case MotionEvent.ACTION_UP:
    133                 if (mDownOnButton) {
    134                     if (mOnClickListener != null && inUndoButton(event)) {
    135                         mOnClickListener.onClick(this);
    136                     }
    137                     mDownOnButton = false;
    138                 }
    139                 break;
    140             case MotionEvent.ACTION_CANCEL:
    141                 mDownOnButton = false;
    142                 break;
    143         }
    144         return true;
    145     }
    146 
    147     // Check if the event is on the right of the separator
    148     private boolean inUndoButton(MotionEvent event) {
    149         float x = event.getX();
    150         float y = event.getY();
    151         int w = getWidth();
    152         int h = getHeight();
    153         return (x >= w - mClickRegion && x < w && y >= 0 && y < h);
    154     }
    155 
    156     ////////////////////////////////////////////////////////////////////////////
    157     //  Alpha Animation
    158     ////////////////////////////////////////////////////////////////////////////
    159 
    160     private static final long NO_ANIMATION = -1;
    161     private static long ANIM_TIME = 200;
    162     private long mAnimationStartTime = NO_ANIMATION;
    163     private float mFromAlpha, mToAlpha;
    164     private float mAlpha;
    165 
    166     private static float getTargetAlpha(int visibility) {
    167         return (visibility == VISIBLE) ? 1f : 0f;
    168     }
    169 
    170     @Override
    171     public void setVisibility(int visibility) {
    172         mAlpha = getTargetAlpha(visibility);
    173         mAnimationStartTime = NO_ANIMATION;
    174         super.setVisibility(visibility);
    175         invalidate();
    176     }
    177 
    178     public void animateVisibility(int visibility) {
    179         float target = getTargetAlpha(visibility);
    180         if (mAnimationStartTime == NO_ANIMATION && mAlpha == target) return;
    181         if (mAnimationStartTime != NO_ANIMATION && mToAlpha == target) return;
    182 
    183         mFromAlpha = mAlpha;
    184         mToAlpha = target;
    185         mAnimationStartTime = AnimationTime.startTime();
    186 
    187         super.setVisibility(VISIBLE);
    188         invalidate();
    189     }
    190 
    191     private void advanceAnimation() {
    192         if (mAnimationStartTime == NO_ANIMATION) return;
    193 
    194         float delta = (float) (AnimationTime.get() - mAnimationStartTime) /
    195                 ANIM_TIME;
    196         mAlpha = mFromAlpha + ((mToAlpha > mFromAlpha) ? delta : -delta);
    197         mAlpha = Utils.clamp(mAlpha, 0f, 1f);
    198 
    199         if (mAlpha == mToAlpha) {
    200             mAnimationStartTime = NO_ANIMATION;
    201             if (mAlpha == 0) {
    202                 super.setVisibility(INVISIBLE);
    203             }
    204         }
    205         invalidate();
    206     }
    207 }
    208