uCrop图片裁剪

2018-03-02 08:28:52来源:cnblogs.com作者:ganchuanpu人点击

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uCrop使用

github地址

https://github.com/Yalantis/uCrop
然后clone或下载到本地,运行之。

效果预览

app/build.gradle

compile 'com.yalantis:ucrop:1.5.0'

AndroidManifest.xml

1 <activity2     android:name="com.yalantis.ucrop.UCropActivity"3     android:screenOrientation="portrait"4     android:theme="@style/Theme.AppCompat.Light.NoActionBar" />

这里theme可以改成自己的

配置uCrop

 1  /** 2   * 启动裁剪 3   * @param activity 上下文 4   * @param sourceFilePath 需要裁剪图片的绝对路径 5   * @param requestCode 比如:UCrop.REQUEST_CROP 6   * @param aspectRatioX 裁剪图片宽高比 7   * @param aspectRatioY 裁剪图片宽高比 8   * @return 9   */10 public static String startUCrop(Activity activity, String sourceFilePath, 11     int requestCode, float aspectRatioX, float aspectRatioY) {12     Uri sourceUri = Uri.fromFile(new File(sourceFilePath));13     File outDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);14     if (!outDir.exists()) {15         outDir.mkdirs();16     }17     File outFile = new File(outDir, System.currentTimeMillis() + ".jpg");18     //裁剪后图片的绝对路径19     String cameraScalePath = outFile.getAbsolutePath();20     Uri destinationUri = Uri.fromFile(outFile);21     //初始化,第一个参数:需要裁剪的图片;第二个参数:裁剪后图片22     UCrop uCrop = UCrop.of(sourceUri, destinationUri);23     //初始化UCrop配置24     UCrop.Options options = new UCrop.Options();25     //设置裁剪图片可操作的手势26     options.setAllowedGestures(UCropActivity.SCALE, UCropActivity.ROTATE, UCropActivity.ALL);27     //是否隐藏底部容器,默认显示28     options.setHideBottomControls(true);29     //设置toolbar颜色30     options.setToolbarColor(ActivityCompat.getColor(activity, R.color.colorPrimary));31     //设置状态栏颜色32     options.setStatusBarColor(ActivityCompat.getColor(activity, R.color.colorPrimary));33     //是否能调整裁剪框34     options.setFreeStyleCropEnabled(true);35     //UCrop配置36     uCrop.withOptions(options);37     //设置裁剪图片的宽高比,比如16:938     uCrop.withAspectRatio(aspectRatioX, aspectRatioY);39     //uCrop.useSourceImageAspectRatio();40     //跳转裁剪页面41     uCrop.start(activity, requestCode);42     return cameraScalePath;43 }

其他配置

 1 //设置Toolbar标题 2 void setToolbarTitle(@Nullable String text) 3 //设置裁剪的图片格式 4 void setCompressionFormat(@NonNull Bitmap.CompressFormat format) 5 //设置裁剪的图片质量,取值0-100 6 void setCompressionQuality(@IntRange(from = 0) int compressQuality) 7 //设置最多缩放的比例尺 8 void setMaxScaleMultiplier(@FloatRange(from = 1.0, fromInclusive = false) float maxScaleMultiplier) 9 //动画时间10 void setImageToCropBoundsAnimDuration(@IntRange(from = 100) int durationMillis)11 //设置图片压缩最大值12 void setMaxBitmapSize(@IntRange(from = 100) int maxBitmapSize)13 //是否显示椭圆裁剪框阴影14 void setOvalDimmedLayer(boolean isOval) 15 //设置椭圆裁剪框阴影颜色16 void setDimmedLayerColor(@ColorInt int color)17 //是否显示裁剪框18 void setShowCropFrame(boolean show)19 //设置裁剪框边的宽度20 void setCropFrameStrokeWidth(@IntRange(from = 0) int width)21 //是否显示裁剪框网格22 void setShowCropGrid(boolean show) 23 //设置裁剪框网格颜色24 void setCropGridColor(@ColorInt int color)25 //设置裁剪框网格宽26 void setCropGridStrokeWidth(@IntRange(from = 0) int width)

onActivityResult

经过裁剪,返回结果,这里我一般只需要裁剪后的图片绝对路径(调用上面startUCrop,即返回图片路径),然后调接口上传服务器。

1 @Override2 public void onActivityResult(int requestCode, int resultCode, Intent data) {3     if (resultCode == RESULT_OK && requestCode == UCrop.REQUEST_CROP) {4         final Uri resultUri = UCrop.getOutput(data);5     } else if (resultCode == UCrop.RESULT_ERROR) {6         final Throwable cropError = UCrop.getError(data);7     }8 }

uCrop源码浅析

uCrop源码能学习的东西有很多,比如左右滑的标尺,不过我们这里源码浅析只关注裁剪部分。

类关系

首先有个大概了解:

GestureCropImageView:负责监听各种手势
CropImageView:主要完成图片裁剪工作,和判断裁剪图片是否充满裁剪框
TransformImageView:负责图片旋转、缩放、位移操作

入口

由上面的效果图可知,点击右上角,调用裁剪操作,代码如下:

 1 @Override 2 public boolean onOptionsItemSelected(MenuItem item) { 3     if (item.getItemId() == R.id.menu_crop) { 4         cropAndSaveImage(); 5     } 6     return super.onOptionsItemSelected(item); 7 } 8 //裁剪和保存图片 9 protected void cropAndSaveImage() {10     ……11     mGestureCropImageView.cropAndSaveImage(mCompressFormat, mCompressQuality, new BitmapCropCallback() {12         @Override13         public void onBitmapCropped(@NonNull Uri resultUri) {14             setResultUri(resultUri, mGestureCropImageView.getTargetAspectRatio());15             finish();16         }17         @Override18         public void onCropFailure(@NonNull Throwable t) {19             setResultError(t);20             finish();21         }22     });23 }

这里调用了GestureCropImageView&cropAndSaveImage方法,如下:

 1 /** 2  * @param compressFormat  图片压缩格式 3  * @param compressQuality 图片压缩质量 4  * @param cropCallback    图片压缩回调 5  */ 6 public void cropAndSaveImage(@NonNull Bitmap.CompressFormat compressFormat, int                                             compressQuality,@Nullable BitmapCropCallback cropCallback) { 7     //取消所有动画 8     cancelAllAnimations(); 9     //判断裁剪图片是否充满裁剪框10     setImageToWrapCropBounds(false);11     //进行裁剪12     new BitmapCropTask(getViewBitmap(), mCropRect, RectUtils.trapToRect(mCurrentImageCorners),13             getCurrentScale(), getCurrentAngle(),14             mMaxResultImageSizeX, mMaxResultImageSizeY,15             compressFormat, compressQuality,16             getImageInputPath(), getImageOutputPath(),17             cropCallback).execute();18 }

裁剪之前

setImageToWrapCropBounds

裁剪之前,先判断裁剪图片是否充满裁剪框,如果没有,进行移动和缩放让其充满。

 1 public void setImageToWrapCropBounds(boolean animate) { 2     //mBitmapLaidOut图片加载OK,isImageWrapCropBounds()检查图片是否充满裁剪框 3     if (mBitmapLaidOut && !isImageWrapCropBounds()) { 4         //当前图片中心X点 5         float currentX = mCurrentImageCenter[0]; 6         //当前图片中心Y点 7         float currentY = mCurrentImageCenter[1]; 8         //当前图片缩放值 9         float currentScale = getCurrentScale();10         //差量11         float deltaX = mCropRect.centerX() - currentX;12         float deltaY = mCropRect.centerY() - currentY;13         float deltaScale = 0;14         //临时矩阵重置15         mTempMatrix.reset();16         //临时矩阵移动17         mTempMatrix.setTranslate(deltaX, deltaY);18         //复制到新的数组19         final float[] tempCurrentImageCorners = Arrays.copyOf(mCurrentImageCorners, mCurrentImageCorners.length);20         //将此矩阵应用于二维点的数组,并编写转换后的指向数组的点21         mTempMatrix.mapPoints(tempCurrentImageCorners);22         //再检查图片是否充满裁剪框23         boolean willImageWrapCropBoundsAfterTranslate = isImageWrapCropBounds(tempCurrentImageCorners);24         if (willImageWrapCropBoundsAfterTranslate) {25             //图片缩进的数组26             final float[] imageIndents = calculateImageIndents();27             deltaX = -(imageIndents[0] + imageIndents[2]);28             deltaY = -(imageIndents[1] + imageIndents[3]);29         } else {30             RectF tempCropRect = new RectF(mCropRect);31             mTempMatrix.reset();32             mTempMatrix.setRotate(getCurrentAngle());33             mTempMatrix.mapRect(tempCropRect);34             //获取裁剪图片的边35             final float[] currentImageSides = RectUtils.getRectSidesFromCorners(mCurrentImageCorners);36             deltaScale = Math.max(tempCropRect.width() / currentImageSides[0],37                     tempCropRect.height() / currentImageSides[1]);38             deltaScale = deltaScale * currentScale - currentScale;39         }40         if (animate) {41             //移动或缩放图片(有动画效果)42             post(mWrapCropBoundsRunnable = new WrapCropBoundsRunnable(43                     CropImageView.this, mImageToWrapCropBoundsAnimDuration, currentX, currentY, deltaX, deltaY,44                     currentScale, deltaScale, willImageWrapCropBoundsAfterTranslate));45         } else {46             //移动图片47             postTranslate(deltaX, deltaY);48             if (!willImageWrapCropBoundsAfterTranslate) {49                 //缩放图片50                 zoomInImage(currentScale + deltaScale, mCropRect.centerX(), mCropRect.centerY());51             }52         }53     }54 }

进行裁剪

裁剪放到了异步,即BitmapCropTask继承AsyncTask,先设置原始图片resizeScale值,然后通过ExifInterface保存新的图片,即裁剪后的图片

  1 public class BitmapCropTask extends AsyncTask<Void, Void, Throwable> {  2       3     ……  4     /**  5      * @param viewBitmap          裁剪图片bitmap  6      * @param cropRect            裁剪矩形  7      * @param currentImageRect    当前图片矩形  8      * @param currentScale        当前图片缩放值  9      * @param currentAngle        当前图片角度 10      * @param maxResultImageSizeX 图片裁剪后最大宽值 11      * @param maxResultImageSizeY 图片裁剪后最大高值 12      * @param compressFormat      图片裁剪的格式 13      * @param compressQuality     图片裁剪的质量 14      * @param imageInputPath      裁剪图片路径 15      * @param imageOutputPath     图片裁剪后路径 16      * @param cropCallback        裁剪回调 17      */ 18     public BitmapCropTask(@Nullable Bitmap viewBitmap, 19                           @NonNull RectF cropRect, @NonNull RectF currentImageRect, 20                           float currentScale, float currentAngle, 21                           int maxResultImageSizeX, int maxResultImageSizeY, 22                           @NonNull Bitmap.CompressFormat compressFormat, int compressQuality, 23                           @NonNull String imageInputPath, @NonNull String imageOutputPath, 24                           @Nullable BitmapCropCallback cropCallback) { 25       …… 26     } 27     @Override 28     @Nullable 29     protected Throwable doInBackground(Void... params) { 30         if (mViewBitmap == null || mViewBitmap.isRecycled()) { 31             return new NullPointerException("ViewBitmap is null or already recycled"); 32         } 33         if (mCurrentImageRect.isEmpty()) { 34             return new NullPointerException("CurrentImageRect is empty"); 35         } 36         //设置resizeScale值 37         float resizeScale = resize(); 38         try { 39             //裁剪 40             crop(resizeScale); 41             //回收 42             mViewBitmap.recycle(); 43             mViewBitmap = null; 44         } catch (Throwable throwable) { 45             return throwable; 46         } 47         return null; 48     } 49     private float resize() { 50         //初始Options 51         final BitmapFactory.Options options = new BitmapFactory.Options(); 52         //查询该位图,而无需分配存储器,可获取outHeight(图片原始高度)和 outWidth(图片的原始宽度) 53         options.inJustDecodeBounds = true; 54         //裁剪图片解码 55         BitmapFactory.decodeFile(mImageInputPath, options); 56         //原始图片和裁剪后图片比值 57         float scaleX = options.outWidth / mViewBitmap.getWidth(); 58         float scaleY = options.outHeight / mViewBitmap.getHeight(); 59         float resizeScale = Math.min(scaleX, scaleY); 60         mCurrentScale /= resizeScale; 61         //初始化值为1 62         resizeScale = 1; 63         if (mMaxResultImageSizeX > 0 && mMaxResultImageSizeY > 0) { 64             float cropWidth = mCropRect.width() / mCurrentScale; 65             float cropHeight = mCropRect.height() / mCurrentScale; 66             if (cropWidth > mMaxResultImageSizeX || cropHeight > mMaxResultImageSizeY) { 67                 scaleX = mMaxResultImageSizeX / cropWidth; 68                 scaleY = mMaxResultImageSizeY / cropHeight; 69                 //设置resizeScale,如果是2就是高度和宽度都是原始的一半 70                 resizeScale = Math.min(scaleX, scaleY); 71                 mCurrentScale /= resizeScale; 72             } 73         } 74         return resizeScale; 75     } 76     private boolean crop(float resizeScale) throws IOException { 77         //ExifInterface这个接口提供了图片文件的旋转,gps,时间等信息,从原始图片读出Exif标签 78         ExifInterface originalExif = new ExifInterface(mImageInputPath); 79         int top = Math.round((mCropRect.top - mCurrentImageRect.top) / mCurrentScale); 80         int left = Math.round((mCropRect.left - mCurrentImageRect.left) / mCurrentScale); 81         int width = Math.round(mCropRect.width() / mCurrentScale); 82         int height = Math.round(mCropRect.height() / mCurrentScale); 83         //复制图片 84         boolean cropped = cropCImg(mImageInputPath, mImageOutputPath, 85                 left, top, width, height, mCurrentAngle, resizeScale, 86                 mCompressFormat.ordinal(), mCompressQuality); 87         if (cropped) { 88             //拿到裁剪后图片 89             copyExif(originalExif, width, height); 90         } 91         return cropped; 92     } 93     @SuppressWarnings("JniMissingFunction") 94     native public boolean cropCImg(String inputPath, String outputPath, 95                                    int left, int top, int width, int height, float angle, float resizeScale, 96                                    int format, int quality) throws IOException, OutOfMemoryError; 97     /** 98      * @param originalExif 原始图片Exif 99      * @param width        裁剪后图片宽100      * @param height       裁剪后图片高101      * @throws IOException 是否异常102      */103     public void copyExif(ExifInterface originalExif, int width, int height) throws IOException {104         //Exif标签数组105         String[] attributes = new String[]{106                 ExifInterface.TAG_APERTURE,107                 ……108         };109         //指定裁剪后图片路径,初始化新的ExifInterface110         ExifInterface newExif = new ExifInterface(mImageOutputPath);111         String value;112         for (String attribute : attributes) {113             value = originalExif.getAttribute(attribute);114             if (!TextUtils.isEmpty(value)) {115                 //设置Exif标签116                 newExif.setAttribute(attribute, value);117             }118         }119         newExif.setAttribute(ExifInterface.TAG_IMAGE_WIDTH, String.valueOf(width));120         newExif.setAttribute(ExifInterface.TAG_IMAGE_LENGTH, String.valueOf(height));121         newExif.setAttribute(ExifInterface.TAG_ORIENTATION, "0");122         //保存123         newExif.saveAttributes();124     }125     @Override126     protected void onPostExecute(@Nullable Throwable t) {127         if (mCropCallback != null) {128             if (t == null) {129                 //接口回调,over130                 mCropCallback.onBitmapCropped(Uri.fromFile(new File(mImageOutputPath)));131             } else {132                 mCropCallback.onCropFailure(t);133             }134         }135     }136 }

总结

uCrop功能强大,对于我来说,有很多东西值得学习,难点如Rect包含问题(其实这块还不是很理解),新知识如ExifInterface操作图片,BitmapFactory显示图片的知识点温故等,还有自定义左右滑的标尺,都是不错的学习源码。抛砖引玉至此,over。

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