Change MDCChipField to use UITextField instead of MDCTextField.

PiperOrigin-RevId: 591304366

components/Chips/examples/ChipsFieldDeleteEnabledViewController.swift

@@ -37,9 +37,12 @@ class ChipsFieldDeleteEnabledViewController: UIViewController, MDCChipFieldDeleg
     view.backgroundColor = containerScheming.colorScheme.backgroundColor
     chipField.frame = .zero
     chipField.delegate = self
-    chipField.textField.placeholderLabel.text = "This is a chip field."
+    let placeholderAttributes: [NSAttributedString.Key: Any] = [
+      .foregroundColor: UIColor.placeholderText
+    ]
+    chipField.placeholderAttributes = placeholderAttributes
+    chipField.placeholder = "This is a chip field."
     chipField.backgroundColor = containerScheming.colorScheme.surfaceColor
-    chipField.showChipsDeleteButton = true
     view.addSubview(chipField)
   }
 

components/Chips/examples/ChipsInputExampleViewController.m

@@ -12,12 +12,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#import "MaterialChips.h"
-#import "MaterialChips+Theming.h"
-#import "MaterialTextFields.h"
-#import "MaterialColorScheme.h"
-#import "MaterialContainerScheme.h"
-#import "MaterialTypographyScheme.h"
+#import "MDCChipField.h"
+#import "MDCChipFieldDelegate.h"
+#import "MDCChipView.h"
+#import "MDCChipView+MaterialTheming.h"
+#import "MDCContainerScheme.h"
+#import "MDCTypographyScheme.h"
 
 @interface ChipsInputExampleViewController : UIViewController <MDCChipFieldDelegate>
 @property(nonatomic, strong) MDCContainerScheme *containerScheme;
@@ -42,26 +42,17 @@ - (void)viewDidLoad {
   typographyScheme.useCurrentContentSizeCategoryWhenApplied = YES;
   self.containerScheme.typographyScheme = typographyScheme;
 
-  if (self.containerScheme.colorScheme) {
-    self.view.backgroundColor = self.containerScheme.colorScheme.backgroundColor;
-  } else {
-    MDCSemanticColorScheme *colorScheme =
-        [[MDCSemanticColorScheme alloc] initWithDefaults:MDCColorSchemeDefaultsMaterial201804];
-    self.view.backgroundColor = colorScheme.backgroundColor;
-  }
+  self.view.backgroundColor = UIColor.systemBackgroundColor;
 
   self.chipField = [[MDCChipField alloc] initWithFrame:CGRectZero];
   self.chipField.delegate = self;
   self.chipField.textField.accessibilityIdentifier = @"chip_field_text_field";
-  self.chipField.textField.placeholderLabel.text = @"This is a chip field.";
-  self.chipField.textField.mdc_adjustsFontForContentSizeCategory = YES;
-  if (self.containerScheme.colorScheme) {
-    self.chipField.backgroundColor = self.containerScheme.colorScheme.surfaceColor;
-  } else {
-    MDCSemanticColorScheme *colorScheme =
-        [[MDCSemanticColorScheme alloc] initWithDefaults:MDCColorSchemeDefaultsMaterial201804];
-    self.chipField.backgroundColor = colorScheme.surfaceColor;
-  }
+  NSDictionary<NSString *, id> *placeholderAttributes =
+      @{NSForegroundColorAttributeName : UIColor.placeholderTextColor};
+  self.chipField.placeholderAttributes = placeholderAttributes;
+  self.chipField.placeholder = @"This is a chip field.";
+  self.chipField.textField.adjustsFontForContentSizeCategory = YES;
+  self.chipField.backgroundColor = UIColor.systemBackgroundColor;
   [self.view addSubview:self.chipField];
 
   // When Dynamic Type changes we need to invalidate the collection view layout in order to let the

components/Chips/src/MDCChipField.h

@@ -16,7 +16,6 @@
 #import <UIKit/UIKit.h>
 
 #import "MDCChipView.h"
-#import "MaterialTextFields.h"
 
 /**
  Note: There is a UIKit bug affecting iOS 8.0-8.2 where UITextFields do not properly call the
@@ -60,7 +59,7 @@ typedef NS_OPTIONS(NSUInteger, MDCChipFieldDelimiter) {
 
 /**
   This class provides an "input chips" experience on iOS, where chip creation is
- coordinated with a user's text input. It manages an @c MDCTextField and a series of @c
+ coordinated with a user's text input. It manages a @c UITextField and a series of @c
  MDCChipViews. When the user hits the return key, new chips are added. When the client hits the
  delete button and the text field has no text, the last chip is deleted.
 
@@ -80,7 +79,7 @@ typedef NS_OPTIONS(NSUInteger, MDCChipFieldDelimiter) {
  If you set a custom font, make sure to also set the custom font on textField.placeholderLabel and
  on your MDCChipView instances.
  */
-@property(nonatomic, nonnull, readonly) MDCTextField *textField;
+@property(nonatomic, nonnull, readonly) UITextField *textField;
 
 /**
  The fixed height of all chip views.
@@ -142,6 +141,18 @@ typedef NS_OPTIONS(NSUInteger, MDCChipFieldDelimiter) {
  */
 @property(nonatomic, nullable, strong) UIImage *deleteButtonImage;
 
+/**
+ The string to be used as the attributed placeholder for the UITextField associated
+ with a chip field.
+ */
+@property(nonatomic, nullable, copy) NSString *placeholder;
+
+/**
+ The attributes applied to the attributed placeholder in the UITextField associated with a
+ chip field.
+ */
+@property(nonatomic, nullable, copy) NSDictionary<NSAttributedStringKey, id> *placeholderAttributes;
+
 /**
  Adds a chip to the chip field.