[rAc OSX] Animate the dots in the "Loading ..." message.

chrome/browser/ui/cocoa/autofill/autofill_loading_shield_controller.mm

+// Copyright 2013 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.
+
+#import "chrome/browser/ui/cocoa/autofill/autofill_loading_shield_controller.h"
+
+#include <cmath>
+
+#include "base/strings/sys_string_conversions.h"

[groby-ooo-7-16, 2013/11/15 23:03:38]

base/mac/scoped_nsobject.h

[Ilya Sherman, 2013/11/16 00:31:13]

Already included in the header, and this #include is actually necessary now that
I've switched setMessage: over to update: instead.

+#include "chrome/browser/ui/autofill/loading_animation.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/gfx/animation/animation_delegate.h"
+
+namespace {
+
+// Horizontal spacing between the animated dots.
+const CGFloat kDotsHorizontalPadding = 3;
+
+}  // namespace
+
+
+// A C++ bridge class for driving the animation.
+class AutofillLoadingAnimationBridge : public gfx::AnimationDelegate {
+ public:
+  AutofillLoadingAnimationBridge(AutofillLoadingShieldController* controller)
+      : animation_(this),
+        controller_(controller) {}
+  virtual ~AutofillLoadingAnimationBridge() {}
+
+  // gfx::AnimationDelegate implementation.
+  virtual void AnimationProgressed(const gfx::Animation* animation) OVERRIDE {
+    DCHECK_EQ(animation, &animation_);
+    [controller_ performLayout];

[groby-ooo-7-16, 2013/11/15 23:03:38]

performLayoutWithAnimation:

You always need the animation, so no need for a separate accessor.

[Ilya Sherman, 2013/11/16 00:31:13]

Done.

+  }
+
+  autofill::LoadingAnimation* animation() { return &animation_; }
+
+ private:
+  autofill::LoadingAnimation animation_;
+  AutofillLoadingShieldController* const controller_;

[groby-ooo-7-16, 2013/11/15 23:03:38]

Probably worth pointing out it's not owned.

[Ilya Sherman, 2013/11/16 00:31:13]

Done.

+};
+
+
+// A simple opaque view for drawing the background of the loading shield.
+@interface AutofillOpaqueView : NSView

[groby-ooo-7-16, 2013/11/15 23:03:38]

Kill this, use NSBox.

Needs a few items set:
[box setBoxType:NSBoxCustom];
[box setBorderType:NSNoBorder];
[box setContentViewMargins:NSZeroSize];
[box setTitlePosition:NSNoTitle];

[Ilya Sherman, 2013/11/16 00:31:13]

Done.

+@end
+
+@implementation AutofillOpaqueView
+
+- (BOOL)isOpaque {
+  return YES;
+}
+
+- (void)drawRect:(NSRect)dirtyRect {
+  [[[self window] backgroundColor] setFill];
+  [NSBezierPath fillRect:[self bounds]];
+}
+
+@end
+
+
+@implementation AutofillLoadingShieldController
+
+- (id)init {
+  if (self = [super initWithNibName:nil bundle:nil]) {
+    animationDriver_.reset(new AutofillLoadingAnimationBridge(self));
+
+    base::scoped_nsobject<NSView> view(
+        [[AutofillOpaqueView alloc] initWithFrame:NSZeroRect]);
+
+    message_.reset([[NSTextField alloc] initWithFrame:NSZeroRect]);
+    ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
+    NSFont* font =
+        rb.GetFont(ui::ResourceBundle::BaseFont).DeriveFont(15).GetNativeFont();
+    [message_ setFont:font];
+    [message_ setEditable:NO];
+    [message_ setBordered:NO];
+    [message_ setDrawsBackground:NO];
+    [view addSubview:message_];
+
+    dots_.reset([[NSArray alloc] initWithArray:@[
+         [[NSTextField alloc] initWithFrame:NSZeroRect],
+         [[NSTextField alloc] initWithFrame:NSZeroRect],
+         [[NSTextField alloc] initWithFrame:NSZeroRect] ]]);
+    for (NSTextField* dot in dots_.get()) {
+      [dot setFont:font];
+      [dot setEditable:NO];
+      [dot setBordered:NO];
+      [dot setDrawsBackground:NO];
+      [dot setStringValue:@"."];
+      [dot sizeToFit];
+      [view addSubview:dot];
+    }
+
+    [self setView:view];
+  }
+  return self;
+}
+
+- (NSString*)message {
+  return [message_ stringValue];
+}
+
+- (void)setMessage:(NSString*)message {
+  [message_ setStringValue:message];
+  [message_ sizeToFit];
+
+  if ([message length] > 0)
+    animationDriver_->animation()->Start();
+  else
+    animationDriver_->animation()->Reset();

[groby-ooo-7-16, 2013/11/15 23:03:38]

You probably want a performLayout here. In general, it seems message of 0 length
is supposed to stop animation - do we want to hide/disable the dots, too? 

[Ilya Sherman, 2013/11/16 00:31:13]

This hides the shield, so there's not much reason to performLayout().  Hopefully
that's clearer with the current structure of the code.

+}
+
+- (NSSize)preferredSize {
+  NOTREACHED();  // Only implemented as part of AutofillLayout protocol.
+  return NSZeroSize;
+}
+
+- (void)performLayout {
+  if ([[self view] isHidden])
+    return;
+
+  NSRect bounds = [[self view] bounds];
+  NSRect messageFrame = [message_ frame];
+
+  CGFloat width = NSWidth(messageFrame);
+  CGFloat height = NSHeight(messageFrame);
+  for (NSView* dot in dots_.get()) {
+    width += NSWidth([dot frame]) + kDotsHorizontalPadding;
+    height = std::max(height, NSHeight([dot frame]));
+  }

[groby-ooo-7-16, 2013/11/15 23:03:38]

We should be able to compute this up front, in setMessage. (I'm reluctant to
compute a centering rectangle on demand - if height ever changes, the loading
message will wobble)

Ideally, do the centering and placing of the dots in a separate routine from
just the dot animation.

[Ilya Sherman, 2013/11/16 00:31:13]

performLayout is now only ever called by the window controller's relayouting. 
Do you still think it's worth caching the width?  (My gut preference is always
to reduce caching unless there's some evidence for the need -- caching tends to
be fragile.)

+
+  // The message + dots should be centered in the view.
+  messageFrame.origin.x = std::ceil((NSWidth(bounds) - width) / 2.0);
+  messageFrame.origin.y = std::ceil((NSHeight(bounds) - height) / 2.0);
+  [message_ setFrame:messageFrame];

[groby-ooo-7-16, 2013/11/15 23:03:38]

[message setFrameOrigin:...]

[Ilya Sherman, 2013/11/16 00:31:13]

Done.

+  for (size_t i = 0; i < [dots_ count]; ++i) {

[groby-ooo-7-16, 2013/11/15 23:03:38]

Avoid manual iteration over NSArray. You need the index for GetCurrentValue, so
set it via setTag: on dot creation and just use [dot tag] to get it in the loop.

[Ilya Sherman, 2013/11/16 00:31:13]

Done.

+    NSView* dot = [dots_ objectAtIndex:i];
+    NSView* previousView = i == 0 ? message_ : [dots_ objectAtIndex:i - 1];
+
+    NSPoint dotFrameOrigin = NSMakePoint(
+        NSMaxX([previousView frame]) + kDotsHorizontalPadding,
+        messageFrame.origin.y -
+            animationDriver_->animation()->GetCurrentValueForDot(i));
+    [dot setFrameOrigin:dotFrameOrigin];
+  }
+}
+
+@end