[CRD iOS] Use an Action Sheet and target the FAB.

remoting/ios/app/host_view_controller.mm

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 #import "remoting/ios/app/host_view_controller.h"
 
@@ skipping 175 matching lines @@
   _client.keyboardInterpreter->HandleDeleteEvent(0);
 }
 
 #pragma mark - Private
 
 - (void)didTap:(id)sender {
   // TODO(nicholss): The FAB is being used to launch an alert window with
   // more options. This is not ideal but it gets us an easy way to make a
   // modal window option selector. Replace this with a real menu later.
 
-  UIAlertController* alert =
-      [UIAlertController alertControllerWithTitle:@"Remote Settings"
-                                          message:nil
-                                   preferredStyle:UIAlertControllerStyleAlert];
+  UIAlertController* alert = [UIAlertController
+      alertControllerWithTitle:@"Remote Settings"
+                       message:nil
+                preferredStyle:UIAlertControllerStyleActionSheet];
 
   if ([self isKeyboardActive]) {
     void (^hideKeyboardHandler)(UIAlertAction*) = ^(UIAlertAction*) {
-      NSLog(@"Will hide keyboard.");
       [self hideKeyboard];
     };
     [alert addAction:[UIAlertAction actionWithTitle:@"Hide Keyboard"
                                               style:UIAlertActionStyleDefault
                                             handler:hideKeyboardHandler]];
   } else {
     void (^showKeyboardHandler)(UIAlertAction*) = ^(UIAlertAction*) {
-      NSLog(@"Will show keyboard.");
       [self showKeyboard];
     };
     [alert addAction:[UIAlertAction actionWithTitle:@"Show Keyboard"
                                               style:UIAlertActionStyleDefault
                                             handler:showKeyboardHandler]];
   }
   void (^disconnectHandler)(UIAlertAction*) = ^(UIAlertAction*) {
     [_client disconnectFromHost];
     [self dismissViewControllerAnimated:YES completion:nil];
   };
   [alert addAction:[UIAlertAction actionWithTitle:@"Disconnect"
-                                            style:UIAlertActionStyleCancel
+                                            style:UIAlertActionStyleDefault
                                           handler:disconnectHandler]];
 
+  void (^cancelHandler)(UIAlertAction*) = ^(UIAlertAction*) {
+    [alert dismissViewControllerAnimated:YES completion:nil];
+  };
+  [alert addAction:[UIAlertAction actionWithTitle:@"Cancel"
+                                            style:UIAlertActionStyleCancel
+                                          handler:cancelHandler]];
+
+  alert.popoverPresentationController.sourceView = self.view;
+  alert.popoverPresentationController.sourceRect =
+      CGRectMake(self.view.bounds.size.width - kFabInset -

[Yuwei, 2017/05/16 20:49:10]

It could be easier to understand if you just do:

CGRectMake(_floatingButton.frame.origin.top,
           _floatingButton.frame.origin.left + width / 2.f,
           1.f, 1.f);

[nicholss, 2017/05/16 21:00:43]

One better:

  alert.popoverPresentationController.sourceRect =
      CGRectMake(_floatingButton.center.x, _floatingButton.frame.origin.y,
                 1.0, 1.0);

Updated.

[Yuwei, 2017/05/16 21:18:54]

Yep. That's much better :)

+                     _floatingButton.frame.size.width / 2.f,
+                 self.view.bounds.size.height - kFabInset -
+                     _floatingButton.frame.size.width,
+                 1.0, 1.0);
+
+  alert.popoverPresentationController.permittedArrowDirections =
+      UIPopoverArrowDirectionDown;
   [self presentViewController:alert animated:YES completion:nil];
 }
 
 @end