| // Copyright 2019-present the Material Components for iOS authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #import <CoreGraphics/CoreGraphics.h> |
| #import <Foundation/Foundation.h> |
| |
| /** |
| Provides APIs for @c UIViews to communicate their elevation throughout the view hierarchy. |
| */ |
| @protocol MDCElevatable <NSObject> |
| |
| /** |
| The current elevation of the conforming @c UIView. |
| */ |
| @property(nonatomic, assign, readonly) CGFloat mdc_currentElevation; |
| |
| /** |
| This block is called when the elevation changes for the conforming @c UIView or @c UIViewController |
| receiver or one of its direct ancestors in the view hierarchy. |
| |
| Use this block to respond to elevation changes in the view or its ancestor views. |
| |
| @param absoluteElevation The @c mdc_currentElevation plus the @c mdc_currentElevation of all |
| ancestor views. This equates to @c mdc_absoluteElevation of the UIView+MaterialElevationResponding |
| category. |
| @param object The receiver (self) which conforms to the protocol. |
| */ |
| @property(nonatomic, copy, nullable) void (^mdc_elevationDidChangeBlock) |
| (id<MDCElevatable> _Nonnull object, CGFloat absoluteElevation); |
| |
| @end |
