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      1 /*
      2  * Copyright (C) 2009 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.camera.ui;
     18 
     19 import android.content.Context;
     20 import android.graphics.Bitmap;
     21 import android.graphics.Canvas;
     22 import android.graphics.Rect;
     23 import android.graphics.drawable.BitmapDrawable;
     24 import android.graphics.drawable.Drawable;
     25 import android.graphics.drawable.TransitionDrawable;
     26 import android.media.ThumbnailUtils;
     27 import android.util.AttributeSet;
     28 import android.view.ViewGroup.LayoutParams;
     29 import android.view.animation.AnimationUtils;
     30 import android.widget.ImageView;
     31 
     32 /**
     33  * A @{code ImageView} which can rotate it's content.
     34  */
     35 public class RotateImageView extends TwoStateImageView implements Rotatable {
     36 
     37     @SuppressWarnings("unused")
     38     private static final String TAG = "RotateImageView";
     39 
     40     private static final int ANIMATION_SPEED = 270; // 270 deg/sec
     41 
     42     private int mCurrentDegree = 0; // [0, 359]
     43     private int mStartDegree = 0;
     44     private int mTargetDegree = 0;
     45 
     46     private boolean mClockwise = false, mEnableAnimation = true;
     47 
     48     private long mAnimationStartTime = 0;
     49     private long mAnimationEndTime = 0;
     50 
     51     public RotateImageView(Context context, AttributeSet attrs) {
     52         super(context, attrs);
     53     }
     54 
     55     public RotateImageView(Context context) {
     56         super(context);
     57     }
     58 
     59     public void enableAnimation(boolean enable) {
     60         mEnableAnimation = enable;
     61     }
     62 
     63     protected int getDegree() {
     64         return mTargetDegree;
     65     }
     66 
     67     // Rotate the view counter-clockwise
     68     public void setOrientation(int degree) {
     69         // make sure in the range of [0, 359]
     70         degree = degree >= 0 ? degree % 360 : degree % 360 + 360;
     71         if (degree == mTargetDegree) return;
     72 
     73         mTargetDegree = degree;
     74         mStartDegree = mCurrentDegree;
     75         mAnimationStartTime = AnimationUtils.currentAnimationTimeMillis();
     76 
     77         int diff = mTargetDegree - mCurrentDegree;
     78         diff = diff >= 0 ? diff : 360 + diff; // make it in range [0, 359]
     79 
     80         // Make it in range [-179, 180]. That's the shorted distance between the
     81         // two angles
     82         diff = diff > 180 ? diff - 360 : diff;
     83 
     84         mClockwise = diff >= 0;
     85         mAnimationEndTime = mAnimationStartTime
     86                 + Math.abs(diff) * 1000 / ANIMATION_SPEED;
     87 
     88         invalidate();
     89     }
     90 
     91     @Override
     92     protected void onDraw(Canvas canvas) {
     93         Drawable drawable = getDrawable();
     94         if (drawable == null) return;
     95 
     96         Rect bounds = drawable.getBounds();
     97         int w = bounds.right - bounds.left;
     98         int h = bounds.bottom - bounds.top;
     99 
    100         if (w == 0 || h == 0) return; // nothing to draw
    101 
    102         if (mCurrentDegree != mTargetDegree) {
    103             long time = AnimationUtils.currentAnimationTimeMillis();
    104             if (time < mAnimationEndTime) {
    105                 int deltaTime = (int)(time - mAnimationStartTime);
    106                 int degree = mStartDegree + ANIMATION_SPEED
    107                         * (mClockwise ? deltaTime : -deltaTime) / 1000;
    108                 degree = degree >= 0 ? degree % 360 : degree % 360 + 360;
    109                 mCurrentDegree = degree;
    110                 invalidate();
    111             } else {
    112                 mCurrentDegree = mTargetDegree;
    113             }
    114         }
    115 
    116         int left = getPaddingLeft();
    117         int top = getPaddingTop();
    118         int right = getPaddingRight();
    119         int bottom = getPaddingBottom();
    120         int width = getWidth() - left - right;
    121         int height = getHeight() - top - bottom;
    122 
    123         int saveCount = canvas.getSaveCount();
    124 
    125         // Scale down the image first if required.
    126         if ((getScaleType() == ImageView.ScaleType.FIT_CENTER) &&
    127                 ((width < w) || (height < h))) {
    128             float ratio = Math.min((float) width / w, (float) height / h);
    129             canvas.scale(ratio, ratio, width / 2.0f, height / 2.0f);
    130         }
    131         canvas.translate(left + width / 2, top + height / 2);
    132         canvas.rotate(-mCurrentDegree);
    133         canvas.translate(-w / 2, -h / 2);
    134         drawable.draw(canvas);
    135         canvas.restoreToCount(saveCount);
    136     }
    137 
    138     private Bitmap mThumb;
    139     private Drawable[] mThumbs;
    140     private TransitionDrawable mThumbTransition;
    141 
    142     public void setBitmap(Bitmap bitmap) {
    143         // Make sure uri and original are consistently both null or both
    144         // non-null.
    145         if (bitmap == null) {
    146             mThumb = null;
    147             mThumbs = null;
    148             setImageDrawable(null);
    149             setVisibility(GONE);
    150             return;
    151         }
    152 
    153         LayoutParams param = getLayoutParams();
    154         final int miniThumbWidth = param.width
    155                 - getPaddingLeft() - getPaddingRight();
    156         final int miniThumbHeight = param.height
    157                 - getPaddingTop() - getPaddingBottom();
    158         mThumb = ThumbnailUtils.extractThumbnail(
    159                 bitmap, miniThumbWidth, miniThumbHeight);
    160         Drawable drawable;
    161         if (mThumbs == null || !mEnableAnimation) {
    162             mThumbs = new Drawable[2];
    163             mThumbs[1] = new BitmapDrawable(getContext().getResources(), mThumb);
    164             setImageDrawable(mThumbs[1]);
    165         } else {
    166             mThumbs[0] = mThumbs[1];
    167             mThumbs[1] = new BitmapDrawable(getContext().getResources(), mThumb);
    168             mThumbTransition = new TransitionDrawable(mThumbs);
    169             setImageDrawable(mThumbTransition);
    170             mThumbTransition.startTransition(500);
    171         }
    172         setVisibility(VISIBLE);
    173     }
    174 }
    175