Singleline <TextInput> now has intrinsic size

Summary:
Singleline <TextInput> now has intrinsic size which is equal to size of placeholder.
And if <TextInput> does not have placeholder it still has intrinsic height.
So, we don't need to set the size up manually every single time anymore!

(Multiline <TextInput> already has this feature.)

Reviewed By: mmmulani

Differential Revision: D5069971

fbshipit-source-id: f65c1062a812259b66d287929314dc571dc1f3ee

Libraries/Text/RCTTextField.h

@@ -11,7 +11,7 @@
 
 #import <React/RCTComponent.h>
 
-@class RCTEventDispatcher;
+@class RCTBridge;
 
 @interface RCTTextField : UITextField
 
@@ -25,6 +25,6 @@
 
 @property (nonatomic, copy) RCTDirectEventBlock onSelectionChange;
 
-- (instancetype)initWithEventDispatcher:(RCTEventDispatcher *)eventDispatcher NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithBridge:(RCTBridge *)bridge NS_DESIGNATED_INITIALIZER;
 
 @end

Libraries/Text/RCTTextField.m

@@ -9,8 +9,10 @@
 
 #import "RCTTextField.h"
 
+#import <React/RCTBridge.h>
 #import <React/RCTConvert.h>
 #import <React/RCTEventDispatcher.h>
+#import <React/RCTUIManager.h>
 #import <React/RCTUtils.h>
 #import <React/UIView+React.h>
 
@@ -47,6 +49,7 @@
 
 @implementation RCTTextField
 {
+  RCTBridge *_bridge;
   RCTEventDispatcher *_eventDispatcher;
   NSInteger _nativeEventCount;
   BOOL _submitted;
@@ -56,17 +59,20 @@
   RCTTextFieldDelegateProxy *_delegateProxy;
 }
 
-- (instancetype)initWithEventDispatcher:(RCTEventDispatcher *)eventDispatcher
+- (instancetype)initWithBridge:(RCTBridge *)bridge
 {
-  if ((self = [super initWithFrame:CGRectZero])) {
-    RCTAssert(eventDispatcher, @"eventDispatcher is a required parameter");
-    _eventDispatcher = eventDispatcher;
+  if (self = [super initWithFrame:CGRectZero]) {
+    RCTAssertParam(bridge);
+
+    _bridge = bridge;
+    _eventDispatcher = bridge.eventDispatcher;
+    _blurOnSubmit = YES;
+
     [self addTarget:self action:@selector(textFieldDidChange) forControlEvents:UIControlEventEditingChanged];
     [self addTarget:self action:@selector(textFieldBeginEditing) forControlEvents:UIControlEventEditingDidBegin];
     [self addTarget:self action:@selector(textFieldEndEditing) forControlEvents:UIControlEventEditingDidEnd];
     [self addTarget:self action:@selector(textFieldSubmitEditing) forControlEvents:UIControlEventEditingDidEndOnExit];
     [self addObserver:self forKeyPath:@"selectedTextRange" options:0 context:nil];
-    _blurOnSubmit = YES;
 
     // We cannot use `self.delegate = self;` here because `UITextField` implements some of these delegate methods itself,
     // so if we implement this delegate on self, we will override some of its behaviours.
@@ -165,6 +171,7 @@ static void RCTUpdatePlaceholder(RCTTextField *self)
 {
   super.placeholder = placeholder;
   RCTUpdatePlaceholder(self);
+  [self updateIntrinsicContentSize];
 }
 
 - (CGRect)caretRectForPosition:(UITextPosition *)position
@@ -186,6 +193,8 @@ static void RCTUpdatePlaceholder(RCTTextField *self)
   return [self textRectForBounds:bounds];
 }
 
+#pragma mark - Events
+
 - (void)textFieldDidChange
 {
   _nativeEventCount++;
@@ -293,6 +302,20 @@ static void RCTUpdatePlaceholder(RCTTextField *self)
   [self reactFocusIfNeeded];
 }
 
+- (void)setFont:(UIFont *)font
+{
+  [super setFont:font];
+  [self updateIntrinsicContentSize];
+}
+
+- (void)updateIntrinsicContentSize
+{
+  NSString *text = self.placeholder ?: @"";
+  CGSize size = [text sizeWithAttributes:@{NSFontAttributeName: self.font}];
+  size = CGSizeMake(RCTCeilPixelValue(size.width), RCTCeilPixelValue(size.height));
+  [_bridge.uiManager setIntrinsicContentSize:size forView:self];
+}
+
 #pragma mark - UITextFieldDelegate (Proxied)
 
 - (BOOL)shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string

Libraries/Text/RCTTextFieldManager.m

@@ -30,7 +30,7 @@ RCT_EXPORT_MODULE()
 
 - (UIView *)view
 {
-  return [[RCTTextField alloc] initWithEventDispatcher:self.bridge.eventDispatcher];
+  return [[RCTTextField alloc] initWithBridge:self.bridge];
 }
 
 RCT_EXPORT_VIEW_PROPERTY(caretHidden, BOOL)