[Dialogs] Adds dismissOnAction property to MDCAlertAction to allow ca…

…llers to control when the dialog dismisses. PiperOrigin-RevId: 358818579
material-components · Feb 22, 2021 · 9c91e26 · 9c91e26
1 parent 2416f19
commit 9c91e26
Show file tree

Hide file tree

Showing 3 changed files with 46 additions and 16 deletions.
diff --git a/components/Dialogs/src/MDCAlertController.h b/components/Dialogs/src/MDCAlertController.h
@@ -444,7 +444,8 @@ typedef void (^MDCActionHandler)(MDCAlertAction *_Nonnull action);
  bottom of an alert controller.
 
  @param title The title of the button shown on the alert dialog.
- @param handler A block to execute when the user selects the action.
+ @param handler A block to execute when the user selects the action. This is called any
+        time the action is selected, even if @c dismissOnAction is @c NO.
  @return An initialized @c MDCActionAlert object.
  */
 + (nonnull instancetype)actionWithTitle:(nonnull NSString *)title
@@ -457,7 +458,8 @@ typedef void (^MDCActionHandler)(MDCAlertAction *_Nonnull action);
  @param emphasis The emphasis of the button that will be rendered in the alert dialog.
         Unthemed actions will render all emphases as text. Apply themers to the alert
         to achieve different appearance for different emphases.
- @param handler A block to execute when the user selects the action.
+ @param handler A block to execute when the user selects the action. This is called any
+        time the action is selected, even if @c dismissOnAction is @c NO.
  @return An initialized @c MDCActionAlert object.
  */
 + (nonnull instancetype)actionWithTitle:(nonnull NSString *)title
@@ -484,4 +486,25 @@ typedef void (^MDCActionHandler)(MDCAlertAction *_Nonnull action);
  */
 @property(nonatomic, nullable, copy) NSString *accessibilityIdentifier;
 
+/**
+ Whether actions dismiss the dialog on action selection or persist the dialog after a selection has
+ been made. If this is set to @c NO, then it is up to the presenting class to dismiss the
+ controller. Callers may dismiss the controller by calling dismissViewControllerAnimated:completion:
+ on the presenting view controller. Ex:
+
+ __weak MDCAlertController *weakAlertController = alertController;
+ MDCAlertAction *action = [MDCAlertAction actionWithTitle:@"Title" handler:^{
+   MDCAlertController *strongAlertController = weakAlertController;
+   if (strongAlertController) {
+     [strongAlertController.presentingViewController dismissViewControllerAnimated:YES
+ completion:nil];
+   }
+ }];
+ action.dismissOnAction = NO;
+ [alertController addAction:action];
+
+ Defaults to @c YES meaning that when an action is performed, it also dismisses the dialog.
+ */
+@property(nonatomic, assign) BOOL dismissOnAction;
+
 @end
diff --git a/components/Dialogs/src/MDCAlertController.m b/components/Dialogs/src/MDCAlertController.m
@@ -28,7 +28,7 @@
 
 @interface MDCAlertAction ()
 
-@property(nonatomic, nullable, copy) MDCActionHandler completionHandler;
+@property(nonatomic, nullable, copy) MDCActionHandler tapHandler;
 
 @end
 
@@ -51,8 +51,9 @@ - (instancetype)initWithTitle:(nonnull NSString *)title
   self = [super init];
   if (self) {
     _title = [title copy];
+    _dismissOnAction = YES;
     _emphasis = emphasis;
-    _completionHandler = [handler copy];
+    _tapHandler = [handler copy];
   }
   return self;
 }
@@ -62,7 +63,7 @@ - (instancetype)initWithTitle:(nonnull NSString *)title
 - (id)copyWithZone:(__unused NSZone *)zone {
   MDCAlertAction *action = [[self class] actionWithTitle:self.title
                                                 emphasis:self.emphasis
-                                                 handler:self.completionHandler];
+                                                 handler:self.tapHandler];
   action.accessibilityIdentifier = self.accessibilityIdentifier;
 
   return action;
@@ -594,16 +595,21 @@ - (void)actionButtonPressed:(id)button forEvent:(UIEvent *)event {
     [self.delegate alertController:self didTapAction:action withEvent:event];
   }
 
-  // We call our action.completionHandler after we dismiss the existing alert in case the handler
-  // also presents a view controller. Otherwise we get a warning about presenting on a controller
-  // which is already presenting.
-  [self.presentingViewController
-      dismissViewControllerAnimated:YES
-                         completion:^(void) {
-                           if (action.completionHandler) {
-                             action.completionHandler(action);
-                           }
-                         }];
+  if (action.dismissOnAction) {
+    // We call our action.tapHandler after we dismiss the existing alert in case the handler
+    // also presents a view controller. Otherwise we get a warning about presenting on a controller
+    // which is already presenting.
+    [self.presentingViewController dismissViewControllerAnimated:YES
+                                                      completion:^(void) {
+                                                        if (action.tapHandler) {
+                                                          action.tapHandler(action);
+                                                        }
+                                                      }];
+  } else {
+    if (action.tapHandler) {
+      action.tapHandler(action);
+    }
+  }
 }
 
 #pragma mark - Text View Delegate

diff --git a/components/Dialogs/src/MDCAlertControllerDelegate.h b/components/Dialogs/src/MDCAlertControllerDelegate.h
@@ -47,7 +47,8 @@
 
 /**
  Called on the delegate after the alert action is tapped by the user and while the alert is still on
- the screen.
+ the screen. This is called whenever the action is tapped regardless of whether it dismisses the
+ alert controller or not.
  */
 - (void)alertController:(nonnull MDCAlertController *)alertController
            didTapAction:(nonnull MDCAlertAction *)action