Android 4.4前后版本读取图库图片和拍照完美解决方案

转载：http://blog.csdn.net/zbjdsbj/article/details/42387551

4.3或以下,选了图片之后,根据Uri来做处理,很多帖子都有了,我就不详细说了. 主要是4.4,如果使用上面pick的原生方法来选图,返回的uri还是正常的,但如果用ACTION_GET_CONTENT的方法,返回的uri跟 4.3是完全不一样的,4.3返回的是带文件路径的,而4.4返回的却是 content://com.android.providers.media.documents/document/image:3951这样的,没 有路径,只有图片编号的uri.这就导致接下来无法根据图片路径来裁剪的步骤了.

来自overflow大牛的方法，4.4得到的uri,需要以下方法来获取文件的路径：

 /**
     * <br>功能简述:4.4及以上获取图片的方法
     * <br>功能详细描述:
     * <br>注意:
     * @param context
     * @param uri
     * @return
     */
    @TargetApi(Build.VERSION_CODES.KITKAT)
    public static String getPath(final Context context, final Uri uri) {
 
        final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
 
        // DocumentProvider
        if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            // ExternalStorageProvider
            if (isExternalStorageDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
 
                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/" + split[1];
                }
            }
            // DownloadsProvider
            else if (isDownloadsDocument(uri)) {
 
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(
                        Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
 
                return getDataColumn(context, contentUri, null, null);
            }
            // MediaProvider
            else if (isMediaDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
 
                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }
 
                final String selection = "_id=?";
                final String[] selectionArgs = new String[] { split[1] };
 
                return getDataColumn(context, contentUri, selection, selectionArgs);
            }
        }
        // MediaStore (and general)
        else if ("content".equalsIgnoreCase(uri.getScheme())) {
 
            // Return the remote address
            if (isGooglePhotosUri(uri))
                return uri.getLastPathSegment();
 
            return getDataColumn(context, uri, null, null);
        }
        // File
        else if ("file".equalsIgnoreCase(uri.getScheme())) {
            return uri.getPath();
        }
 
        return null;
    }
 
    public static String getDataColumn(Context context, Uri uri, String selection,
            String[] selectionArgs) {
 
        Cursor cursor = null;
        final String column = "_data";
        final String[] projection = { column };
 
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
                    null);
            if (cursor != null && cursor.moveToFirst()) {
                final int index = cursor.getColumnIndexOrThrow(column);
                return cursor.getString(index);
            }
        } finally {
            if (cursor != null)
                cursor.close();
        }
        return null;
    }
 
    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is ExternalStorageProvider.
     */
    public static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }
 
    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is DownloadsProvider.
     */
    public static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }
 
    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is MediaProvider.
     */
    public static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }
 
    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is Google Photos.
     */
    public static boolean isGooglePhotosUri(Uri uri) {
        return "com.google.android.apps.photos.content".equals(uri.getAuthority());
    }</span></span>

为什么会不一样呢？

Android 4.4（含）开始，通过方式访问图库后，返回的Uri如下（访问“最近”）：

Uri is：content://com.android.providers.media.documents/document/image%3A18838
2 Uri.getPath is ：/document/image:18838
3 对应的图片真实路径：/storage/emulated/0/Pictures/Screenshots/Screenshot_2014-09-22-21-40-53.png</span>

不但如此，对于不同类型图库，返回的Uri形式并不相同（访问普通相册）：

Uri is：content://media/external/images/media/18822
2 Uri.getPath is ：/external/images/media/18822
3 对应的图片真实路径：/storage/emulated/0/Download/20130224235013.jpg</span>

而4.4之前返回的Uri只存在一种形式，如下：

Uri is：content://media/external/images/media/14046
2 Uri.getPath is ：/external/images/media/14046
3 对应的图片真实路径：/storage/emulated/0/DCIM/Camera/20130224235013.jpg

因此，在Android 4.4或更高版本设备上，通过简单的getDataColumn(Context, Uri, null, null)进行图片数据库已经不能满足所有需求，因此在获取图片真实路径的时候需要根据不同类型区分对待。

版本判断：

//版本比较：是否是4.4及以上版本
    final boolean mIsKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;

从相册选择照片方法比较：

/**
     * <br>功能简述:4.4及以上从相册选择照片
     * <br>功能详细描述:
     * <br>注意:
     */
    @TargetApi(Build.VERSION_CODES.KITKAT)
    private void SelectImageUriAfterKikat() {
        Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
        intent.addCategory(Intent.CATEGORY_OPENABLE);
        intent.setType("image/*");
        startActivityForResult(intent, SELECET_A_PICTURE_AFTER_KIKAT);
    }

/**
     * <br>功能简述:4.4以下从相册选照片并剪切
     * <br>功能详细描述:
     * <br>注意:
     */
    private void cropImageUri() {
        Intent intent = new Intent(Intent.ACTION_GET_CONTENT, null);
        intent.setType("image/*");
        intent.putExtra("crop", "true");
        intent.putExtra("aspectX", 1);
        intent.putExtra("aspectY", 1);
        intent.putExtra("outputX", 640);
        intent.putExtra("outputY", 640);
        intent.putExtra("scale", true);
        intent.putExtra("return-data", false);
        intent.putExtra(MediaStore.EXTRA_OUTPUT,
                Uri.fromFile(new File(IMGPATH, TMP_IMAGE_FILE_NAME)));
        intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
        intent.putExtra("noFaceDetection", true); // no face detection
        startActivityForResult(intent, SELECT_A_PICTURE);
    }

 拍照通用方法，对返回数据做处理： 

/**
     * <br>功能简述:对拍照的图片剪切
     * <br>功能详细描述:
     * <br>注意:
     * @param uri
     */
    private void cameraCropImageUri(Uri uri) {
        Intent intent = new Intent("com.android.camera.action.CROP");
        intent.setDataAndType(uri, "image/jpeg");
        intent.putExtra("crop", "true");
        intent.putExtra("aspectX", 1);
        intent.putExtra("aspectY", 1);
        intent.putExtra("outputX", 640);
        intent.putExtra("outputY", 640);
        intent.putExtra("scale", true);
        if (mIsKitKat) {
            intent.putExtra("return-data", true);
        } else {
            intent.putExtra("return-data", false);
            intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
        }
        intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
        intent.putExtra("noFaceDetection", true);
        startActivityForResult(intent, SET_PICTURE);
    }

显示等处理如下：

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == SELECT_A_PICTURE) {
            if (resultCode == RESULT_OK && null != data) {
                Log.i("zou", "4.4以下的");
                Bitmap bitmap = decodeUriAsBitmap(Uri.fromFile(new File(IMGPATH,
                        TMP_IMAGE_FILE_NAME)));
                mAcountHeadIcon.setImageBitmap(bitmap);
            }
        } else if (requestCode == SELECET_A_PICTURE_AFTER_KIKAT) {
            if (resultCode == RESULT_OK && null != data) {
                Log.i("zou", "4.4以上上的");
                mAlbumPicturePath = getPath(MainActivity.this, data.getData());
                cropImageUriAfterKikat(Uri.fromFile(new File(mAlbumPicturePath)));
            }
        } else if (requestCode == SET_ALBUM_PICTURE_KITKAT) {
            Log.i("zou", "4.4以上上的 RESULT_OK");
            Bitmap bitmap = data.getParcelableExtra("data");
            mAcountHeadIcon.setImageBitmap(bitmap);
        } else if (requestCode == TAKE_A_PICTURE) {
            Log.i("zou", "resultCode:" + resultCode);
            cameraCropImageUri(Uri.fromFile(new File(IMGPATH, IMAGE_FILE_NAME)));
        } else if (requestCode == SET_PICTURE) {
            Log.i("zou", "SET_PICTURE-resultCode:" + resultCode);
 
            Bitmap bitmap = null;
            if (mIsKitKat) {
                if (null != data) {
                    bitmap = data.getParcelableExtra("data");
                }
            } else {
                bitmap = decodeUriAsBitmap(Uri.fromFile(new File(IMGPATH, IMAGE_FILE_NAME)));
            }
            mAcountHeadIcon.setImageBitmap(bitmap);
        }
    }

GIthub工程地址：https://github.com/ZBJDSBJ/CameraDemo