[Shapes] Initial Shape Scheme implementation (#5014)

This PR implements the initial Shape Scheme that is essential for allowing shape theming for components (*this doesn't include any themers and that will be included as a separate PR once this is approved*). More information can be seen in go/mdc-ios-shape-theming and go/material-shapes-eng

This closes #4609 #4612 #4613

MaterialComponents.podspec

@@ -864,6 +864,13 @@ Pod::Spec.new do |mdc|
       scheme.public_header_files = "components/schemes/#{scheme.base_name}/src/*.h"
       scheme.source_files = "components/schemes/#{scheme.base_name}/src/*.{h,m}"
     end
+    scheme_spec.subspec "Shape" do |scheme|
+      scheme.ios.deployment_target = '8.0'
+      scheme.public_header_files = "components/schemes/#{scheme.base_name}/src/*.h"
+      scheme.source_files = "components/schemes/#{scheme.base_name}/src/*.{h,m}"
+      scheme.dependency "MaterialComponents/private/ShapeLibrary"
+      scheme.dependency "MaterialComponents/private/Shapes"
+    end
     scheme_spec.subspec "Typography" do |scheme|
       scheme.ios.deployment_target = '8.0'
       scheme.public_header_files = "components/schemes/#{scheme.base_name}/src/*.h"

components/private/ShapeLibrary/src/MDCCornerTreatment+CornerTypeInitalizer.h

@@ -0,0 +1,27 @@
+// Copyright 2018-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 "MaterialShapes.h"
+
+typedef NS_ENUM(NSInteger, MDCCornerType) {
+  MDCCornerTypeCurved,
+  MDCCornerTypeCut,
+  MDCCornerTypeRounded
+};
+
+@interface MDCCornerTreatment (CornerTypeInitalizer)
+
+- (instancetype)initWithCornerType:(MDCCornerType)cornerType andSize:(NSNumber *)size;
+
+@end

components/private/ShapeLibrary/src/MDCCornerTreatment+CornerTypeInitalizer.m

@@ -0,0 +1,45 @@
+// Copyright 2018-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 "MDCCornerTreatment+CornerTypeInitalizer.h"
+
+#import "MDCCurvedCornerTreatment.h"
+#import "MDCCutCornerTreatment.h"
+#import "MDCRoundedCornerTreatment.h"
+
+@implementation MDCCornerTreatment (CornerTypeInitalizer)
+
+- (instancetype)initWithCornerType:(MDCCornerType)cornerType andSize:(NSNumber *)size {
+  self = [self init];
+  switch (cornerType) {
+    case MDCCornerTypeCurved: {
+      CGSize curvedSize = [size CGSizeValue];
+      self = [[MDCCurvedCornerTreatment alloc] initWithSize:curvedSize];
+      break;
+    }
+    case MDCCornerTypeCut: {
+      CGFloat cutSize = [size floatValue];
+      self = [[MDCCutCornerTreatment alloc] initWithCut:cutSize];
+      break;
+    }
+    case MDCCornerTypeRounded: {
+      CGFloat radiusSize = [size floatValue];
+      self = [[MDCRoundedCornerTreatment alloc] initWithRadius:radiusSize];
+      break;
+    }
+  }
+  return self;
+}
+
+@end

components/private/ShapeLibrary/src/MaterialShapeLibrary.h

@@ -12,10 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#import "MDCCornerTreatment+CornerTypeInitalizer.h"
 #import "MDCCurvedCornerTreatment.h"
 #import "MDCCurvedRectShapeGenerator.h"
+#import "MDCCutCornerTreatment.h"
 #import "MDCPillShapeGenerator.h"
 #import "MDCRoundedCornerTreatment.h"
 #import "MDCSlantedRectShapeGenerator.h"
 #import "MDCTriangleEdgeTreatment.h"
-#import "MDCCutCornerTreatment.h"

components/schemes/Shape/BUILD

@@ -0,0 +1,59 @@
+# Copyright 2018-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.
+
+load("//:material_components_ios.bzl",
+     "mdc_objc_library",
+     "mdc_public_objc_library",
+     "mdc_unit_test_suite")
+
+licenses(["notice"])  # Apache 2.0
+
+mdc_public_objc_library(
+    name = "Shape",
+    deps = [
+        "//components/private/ShapeLibrary",
+    ],
+)
+
+package_group(
+    name = "test_targets",
+    packages = [
+        "//components/schemes/Shape/...",
+    ],
+)
+
+mdc_objc_library(
+    name = "unit_test_sources",
+    testonly = 1,
+    srcs = glob(["tests/unit/*.m"]),
+    hdrs = glob(["tests/unit/*.h"]),
+    includes = ["src"],
+    sdk_frameworks = [
+        "CoreGraphics",
+        "UIKit",
+        "XCTest",
+    ],
+    deps = [
+        ":Shape",
+   ],
+    visibility = ["//visibility:private"],
+)
+
+mdc_unit_test_suite(
+    deps = [
+      ":unit_test_sources",
+    ],
+)

components/schemes/Shape/src/MDCShapeCategory.h

@@ -0,0 +1,68 @@
+// Copyright 2018-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 <Foundation/Foundation.h>
+#import "MDCShapeCorner.h"
+
+/**
+ The MDCShapeCategory is the class containing the shape value as part of our shape scheme,
+ MDCShapeScheme.
+
+ MDCShapeCategory is built from 4 corners, that can be set to alter the shape value.
+ */
+@interface MDCShapeCategory : NSObject
+
+/**
+ This property represents the shape of the top left corner of the shape.
+ */
+@property(strong, nonatomic) MDCShapeCorner *topLeftCorner;
+
+/**
+ This property represents the shape of the top right corner of the shape.
+ */
+@property(strong, nonatomic) MDCShapeCorner *topRightCorner;
+
+/**
+ This property represents the shape of the bottom left corner of the shape.
+ */
+@property(strong, nonatomic) MDCShapeCorner *bottomLeftCorner;
+
+/**
+ This property represents the shape of the bottom right corner of the shape.
+ */
+@property(strong, nonatomic) MDCShapeCorner *bottomRightCorner;
+
+/**
+ The default init of the class. It sets all 4 corners with a corner family of
+ MDCShapeCornerFamilyRounded and size of 0. This is equivalent to a "sharp" corner, or in terms of
+ Apple's API it is the same as setting the cornerRadius to 0.
+
+ @return returns an initialized MDCShapeCategory instance.
+ */
+- (instancetype)init;
+
+/**
+ This method is a convenience initializer of setting the shape value of all our corners at once
+ to the provided cornerFamily and cornerSize.
+
+ The outcome is a symmetrical shape that has the same values for all its corners.
+
+ @param cornerFamily The family of our corner (rounded or angled).
+ @param cornerSize The shape value of the corner.
+ @return returns an MDCShapeCategory with the initialized values.
+ */
+- (instancetype)initCornersWithFamily:(MDCShapeCornerFamily)cornerFamily
+                              andSize:(CGFloat)cornerSize;
+
+@end

components/schemes/Shape/src/MDCShapeCategory.m

@@ -0,0 +1,34 @@
+// Copyright 2018-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 "MDCShapeCategory.h"
+
+@implementation MDCShapeCategory
+
+- (instancetype)init {
+  return [self initCornersWithFamily:MDCShapeCornerFamilyRounded andSize:0];
+}
+
+- (instancetype)initCornersWithFamily:(MDCShapeCornerFamily)cornerFamily
+                              andSize:(CGFloat)cornerSize {
+  if (self = [super init]) {
+    _topLeftCorner = [[MDCShapeCorner alloc] initWithFamily:cornerFamily andSize:cornerSize];
+    _topRightCorner = [[MDCShapeCorner alloc] initWithFamily:cornerFamily andSize:cornerSize];
+    _bottomLeftCorner = [[MDCShapeCorner alloc] initWithFamily:cornerFamily andSize:cornerSize];
+    _bottomRightCorner = [[MDCShapeCorner alloc] initWithFamily:cornerFamily andSize:cornerSize];
+  }
+  return self;
+}
+
+@end

components/schemes/Shape/src/MDCShapeCorner.h

@@ -0,0 +1,93 @@
+// Copyright 2018-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 <Foundation/Foundation.h>
+#import "MaterialShapeLibrary.h"
+
+/**
+ This enum consists of the different types of shape corners.
+
+ - MDCShapeCornerFamilyRounded: A rounded corner.
+ - MDCShapeCornerFamilyAngled: An angled/cut corner.
+ */
+typedef NS_ENUM(NSInteger, MDCShapeCornerFamily) {
+  MDCShapeCornerFamilyRounded,
+  MDCShapeCornerFamilyAngled,
+};
+
+/**
+ This enum consists of the different types of shape values that can be provided.
+
+ - MDCShapeCornerSizeTypeAbsolute: If an absolute shape size is provided.
+ - MDCShapeCornerSizeTypePercentage: If a relative shape size is provided.
+
+ See MDCShapeCorner's @c size property for additional details.
+ */
+typedef NS_ENUM(NSInteger, MDCShapeCornerSizeType) {
+  MDCShapeCornerSizeTypeAbsolute,
+  MDCShapeCornerSizeTypePercentage,
+};
+
+/**
+ An MDCShapeCorner is the shape value of a corner. It takes a family, a size type, and a size.
+ */
+@interface MDCShapeCorner : NSObject
+
+/**
+ The shape family of our corner.
+ */
+@property(assign, nonatomic) MDCShapeCornerFamily family;
+
+/**
+ The size type of our shape.
+ */
+@property(assign, nonatomic) MDCShapeCornerSizeType sizeType;
+
+/**
+ The size of our shape.
+
+ When MDCShapeSizeType is MDCShapeCornerSizeTypeAbsolute, this accepts absolute values
+ that are positive.
+
+ When MDCShapeSizeType is MDCShapeCornerSizeTypePercentage, values are expected to be in the range
+ of 0 to 1 (0% - 100%). These values are percentages based on the height of the surface.
+ */
+@property(assign, nonatomic) CGFloat size;
+
+/**
+ This initializer takes in a shape family and size, and returns a shape corner.
+
+ @param cornerFamily The shape family.
+ @param cornerSize The shape size.
+ @return an MDCShapeCorner.
+ */
+- (instancetype)initWithFamily:(MDCShapeCornerFamily)cornerFamily andSize:(CGFloat)cornerSize;
+
+/**
+ This method returns an MDCCornerTreament representation of the MDCShapeCorner.
+
+ @return an MDCCornerTreatment.
+ */
+- (MDCCornerTreatment *)cornerTreatmentValue;
+
+/**
+ This method returns an MDCCornerTreatment representation of the MDCShapeCorner.
+ It receives the bounds of the shape when a percentage or relative value is given.
+
+ @param bounds The bounds of the shape.
+ @return an MDCCornerTreatment.
+ */
+- (MDCCornerTreatment *)cornerTreatmentValueWithViewBounds:(CGRect)bounds;
+
+@end