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Android调用系统相机和相册-坑篇

之前分享了 Android调用系统相机和相册 ,但是由于国内Android机型繁多,各家都自己的room,调用系统的还是会出现不少问题:

一、拍照后照片被旋转

这种情况是使用Camera拍照以后,得到的照片会被自动旋转(90°、180°、270°)。解决方案:

1、读取图片的旋转属性

/**
* 读取图片的旋转的角度
*
* @param path
* 图片绝对路径
* @return 图片的旋转角度
*/

private int getBitmapDegree(String path) {
int degree = 0;
try {
// 从指定路径下读取图片,并获取其EXIF信息
ExifInterface exifInterface = new ExifInterface(path);
// 获取图片的旋转信息
int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_NORMAL);
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_90:
degree = 90;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
degree = 180;
break;
case ExifInterface.ORIENTATION_ROTATE_270:
degree = 270;
break;
}
} catch (IOException e) {
e.printStackTrace();
}
return degree;
}

2、将图片按照某个角度进行旋转

/**
* 将图片按照某个角度进行旋转
*
* @param bm
* 需要旋转的图片
* @param degree
* 旋转角度
* @return 旋转后的图片
*/


public static Bitmap rotateBitmapByDegree(Bitmap bm, int degree) {
Bitmap returnBm = null;

// 根据旋转角度,生成旋转矩阵
Matrix matrix = new Matrix();
matrix.postRotate(degree);
try {
// 将原始图片按照旋转矩阵进行旋转,并得到新的图片
returnBm = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), matrix, true);
} catch (OutOfMemoryError e) {
}
if (returnBm == null) {
returnBm = bm;
}
if (bm != returnBm) {
bm.recycle();
}
return returnBm;
}

详见博客: https://www.baidufe.com/item/4bb733d9999c53cb8fed.html

二、调用系统相册,拿不到绝对路径

上篇的方法,我在大部分手机测试是可行,但是一些机型还是拿不到,解决方案:

public class AbsolutePathUtil {
public static String getAbsolutePath(final Context context, final Uri uri) {
// DocumentProvider
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT && 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];
}

// TODO handle non-primary volumes
}
// 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 getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}

return null;
}

/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/

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 column_index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(column_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());
}
}

详见stackoverflow: http://stackoverflow.com/questions/13209494/how-to-get-the-full-file-path-from-uri

三、裁剪

拿到图片的绝对路径,有可能需要对它进行裁剪,这里当然也可以调用系统的裁剪,不过我推荐UCrop,功能好强大,简单的使用方法:

/**
* 启动裁剪
*/

public static String startUCrop(Activity activity, String sourceFilePath, int requestCode, float aspectRatioX, float aspectRatioY) {
Uri sourceUri = Uri.fromFile(new File(sourceFilePath));
File outDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
if (!outDir.exists()) {
outDir.mkdirs();
}
File outFile = new File(outDir, System.currentTimeMillis() + ".jpg");
String cameraScalePath = outFile.getAbsolutePath();
Uri destinationUri = Uri.fromFile(outFile);
UCrop uCrop = UCrop.of(sourceUri, destinationUri);
UCrop.Options options = new UCrop.Options();
options.setAllowedGestures(UCropActivity.SCALE, UCropActivity.ROTATE, UCropActivity.ALL);
options.setHideBottomControls(true);
options.setFreeStyleCropEnabled(true);
uCrop.withOptions(options);
uCrop.withAspectRatio(aspectRatioX, aspectRatioY);
uCrop.start(activity, requestCode);
return cameraScalePath;
}

详见github: https://github.com/Yalantis/uCrop

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Android调用系统相机和相册-坑篇

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原文  http://wuxiaolong.me/2016/05/24/Android-Photograph-Album2/
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