[Android] Composited selection handle rendering

content/browser/renderer_host/input/touch_selection_controller.cc

+// Copyright 2014 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.
+
+#include "content/browser/renderer_host/input/touch_selection_controller.h"
+
+#include "base/logging.h"
+
+namespace content {
+
+TouchSelectionController::TouchSelectionController(
+    TouchSelectionControllerClient* client)
+    : client_(client),
+      anchor_orientation_(TOUCH_HANDLE_ORIENTATION_UNDEFINED),
+      anchor_visible_(false),
+      focus_orientation_(TOUCH_HANDLE_ORIENTATION_UNDEFINED),
+      focus_visible_(false),
+      is_insertion_active_(false),
+      allow_automatic_insertion_activation_(false),
+      is_selection_active_(false),
+      allow_automatic_selection_activation_(false),
+      selection_editable_(false),
+      selection_editable_for_last_update_(false) {
+  DCHECK(client_);
+  HideAndDisallowAutomaticShowing();
+}
+
+TouchSelectionController::~TouchSelectionController() {
+}
+
+void TouchSelectionController::OnSelectionBoundsChanged(
+    const gfx::RectF& anchor_rect,
+    TouchHandleOrientation anchor_orientation,
+    bool anchor_visible,
+    const gfx::RectF& focus_rect,
+    TouchHandleOrientation focus_orientation,
+    bool focus_visible) {
+  if (!allow_automatic_selection_activation_ &&
+      !allow_automatic_insertion_activation_)
+    return;
+
+  if (anchor_rect_ == anchor_rect && focus_rect_ == focus_rect &&
+      anchor_orientation_ == anchor_orientation &&
+      focus_orientation_ == focus_orientation &&
+      anchor_visible_ == anchor_visible && focus_visible_ == focus_visible &&
+      selection_editable_ == selection_editable_for_last_update_)
+    return;
+
+  anchor_rect_ = anchor_rect;
+  anchor_orientation_ = anchor_orientation;
+  anchor_visible_ = anchor_visible;
+  focus_rect_ = focus_rect;
+  focus_orientation_ = focus_orientation;
+  focus_visible_ = focus_visible;
+  selection_editable_for_last_update_ = selection_editable_;
+
+  const gfx::PointF anchor = GetAnchorPosition();
+  const gfx::PointF focus = GetFocusPosition();
+  if (anchor.x() != focus.x() || anchor.y() != focus.y() ||

[cjhopman, 2014/07/07 22:13:41]

anchor != focus

[jdduke (slow), 2014/07/08 00:54:44]

Done.

+      (start_selection_handle_ && start_selection_handle_->is_dragging()) ||

[cjhopman, 2014/07/07 22:13:41]

Can this just use is_selection_active_ rather than checking that the handles are
not null? It's not exactly the same as the handle can exist when not active, but
they shouldn't ever be dragging if not active.

[jdduke (slow), 2014/07/08 00:54:44]

Done.

+      (end_selection_handle_ && end_selection_handle_->is_dragging())) {
+    // It's possible that the bounds temporarily overlap while a handle is
+    // being dragged, incorrectly reporting a CENTER orientation.
+    if (anchor_orientation_ == TOUCH_HANDLE_CENTER && start_selection_handle_)

[cjhopman, 2014/07/07 22:13:41]

AIUI, if anchor_orientation_ == TOUCH_HANDLE_CENTER, then
start_selection_handle_ must not be null since one of the selection handles is
being dragged. This block might be clearer if you checked for selection dragging
+ fixed up orientation outside this condition. Something like:

if (check_for_selection_dragging) {
  is_selection_dragging = true
  fixup orientation
}

if (anchor != focus || is_selection_dragging) {
  OnSelectionChanged();
  return;
}

idk if that's any better.

[jdduke (slow), 2014/07/08 00:54:44]

It's definitely better, good call.

+      anchor_orientation_ = start_selection_handle_->orientation();
+    if (focus_orientation_ == TOUCH_HANDLE_CENTER && end_selection_handle_)
+      focus_orientation_ = end_selection_handle_->orientation();
+
+    OnSelectionChanged();
+    return;
+  }
+
+  if (anchor_orientation_ == TOUCH_HANDLE_CENTER) {
+    OnInsertionChanged();
+    return;
+  }
+
+  HideAndDisallowAutomaticShowing();
+}
+
+bool TouchSelectionController::WillHandleTouchEvent(
+    const ui::MotionEvent& event) {
+  if (is_insertion_active_) {
+    DCHECK(insertion_handle_);
+    return insertion_handle_->WillHandleTouchEvent(event);
+  }
+
+  if (is_selection_active_) {
+    DCHECK(start_selection_handle_);
+    DCHECK(end_selection_handle_);
+    return start_selection_handle_->WillHandleTouchEvent(event) ||
+           end_selection_handle_->WillHandleTouchEvent(event);
+  }
+
+  return false;
+}
+
+void TouchSelectionController::AllowAutomaticInsertionShowing() {
+  if (allow_automatic_insertion_activation_)
+    return;
+  allow_automatic_insertion_activation_ = true;
+  if (!is_insertion_active_ && !is_selection_active_)
+    ResetCachedValues();
+}
+
+void TouchSelectionController::AllowAutomaticSelectionShowing() {
+  if (allow_automatic_selection_activation_)
+    return;
+  allow_automatic_selection_activation_ = true;
+  if (!is_insertion_active_ && !is_selection_active_)
+    ResetCachedValues();
+}
+
+void TouchSelectionController::HideAndDisallowAutomaticShowing() {
+  DeactivateInsertion();
+  DeactivateSelection();
+  allow_automatic_insertion_activation_ = false;
+  allow_automatic_selection_activation_ = false;
+}
+
+void TouchSelectionController::OnSelectionEditable(bool editable) {
+  if (selection_editable_ == editable)
+    return;
+  selection_editable_ = editable;
+  if (!selection_editable_)
+    DeactivateInsertion();
+}
+
+bool TouchSelectionController::Animate(base::TimeTicks frame_time) {
+  if (is_insertion_active_)
+    return insertion_handle_->Animate(frame_time);
+
+  if (is_selection_active_) {
+    bool needs_animate = start_selection_handle_->Animate(frame_time);
+    needs_animate |= end_selection_handle_->Animate(frame_time);
+    return needs_animate;
+  }
+
+  return false;
+}
+
+void TouchSelectionController::OnHandleDragBegin(const TouchHandle& handle) {
+  if (&handle == insertion_handle_.get())
+    return;
+
+  if (&handle == start_selection_handle_.get()) {
+    fixed_handle_position_ = end_selection_handle_->position() -
+                             gfx::Vector2dF(0, GetFocusLineHeight() / 2.f);
+  } else {
+    fixed_handle_position_ = start_selection_handle_->position() -
+                             gfx::Vector2dF(0, GetAnchorLineHeight() / 2.f);
+  }
+}
+
+void TouchSelectionController::OnHandleDragUpdate(const TouchHandle& handle,
+                                                  const gfx::PointF& position) {
+  // As the position corresponds to the bottom left point of the selection
+  // bound, offset it by half the corresponding line height.
+  float half_line_height = &handle == end_selection_handle_.get()
+                               ? GetFocusLineHeight() / 2.f
+                               : GetAnchorLineHeight() / 2.f;
+  gfx::PointF line_position = position - gfx::Vector2dF(0, half_line_height);
+  if (&handle == insertion_handle_.get()) {
+    client_->MoveCaret(line_position);
+  } else {
+    client_->SelectBetweenCoordinates(fixed_handle_position_, line_position);
+  }
+}
+
+void TouchSelectionController::OnHandleDragEnd(const TouchHandle& handle) {
+}
+
+void TouchSelectionController::OnHandleTapped(const TouchHandle& handle) {
+  if (insertion_handle_ && &handle == insertion_handle_.get())
+    client_->OnSelectionEvent(INSERTION_TAPPED, GetAnchorPosition());
+}
+
+void TouchSelectionController::SetNeedsAnimate() {
+  client_->SetNeedsAnimate();
+}
+
+scoped_ptr<TouchHandleDrawable> TouchSelectionController::CreateDrawable() {
+  return client_->CreateDrawable();
+}
+
+void TouchSelectionController::OnInsertionChanged() {
+  DeactivateSelection();
+
+  if (!allow_automatic_insertion_activation_ || !selection_editable_)
+    return;
+
+  bool was_active = is_insertion_active_;
+  gfx::PointF position = GetAnchorPosition();
+  if (!was_active)
+    ActivateInsertion();
+  else
+    client_->OnSelectionEvent(INSERTION_MOVED, position);
+
+  if (was_active)
+    insertion_handle_->SetVisibleAnimated(anchor_visible_);
+  else
+    insertion_handle_->SetVisible(anchor_visible_);
+
+  insertion_handle_->SetPosition(position);
+}
+
+void TouchSelectionController::OnSelectionChanged() {
+  DeactivateInsertion();
+
+  if (!allow_automatic_selection_activation_)
+    return;
+
+  const bool was_active = is_selection_active_;
+  ActivateSelection();
+  if (was_active) {
+    start_selection_handle_->SetVisibleAnimated(anchor_visible_);
+    end_selection_handle_->SetVisibleAnimated(focus_visible_);
+  } else {
+    start_selection_handle_->SetVisible(anchor_visible_);
+    end_selection_handle_->SetVisible(focus_visible_);
+  }
+  start_selection_handle_->SetPosition(GetAnchorPosition());
+  end_selection_handle_->SetPosition(GetFocusPosition());
+}
+
+void TouchSelectionController::ActivateInsertion() {
+  DCHECK(!is_selection_active_);
+
+  if (!insertion_handle_)
+    insertion_handle_.reset(new TouchHandle(this, TOUCH_HANDLE_CENTER));
+
+  if (!is_insertion_active_) {
+    is_insertion_active_ = true;
+    client_->OnSelectionEvent(INSERTION_SHOWN, GetAnchorPosition());
+  }
+}
+
+void TouchSelectionController::DeactivateInsertion() {
+  if (!is_insertion_active_)
+    return;
+  DCHECK(insertion_handle_);
+  insertion_handle_->Hide();
+  is_insertion_active_ = false;
+  client_->OnSelectionEvent(INSERTION_CLEARED, gfx::PointF());
+}
+
+void TouchSelectionController::ActivateSelection() {
+  DCHECK(!is_insertion_active_);
+
+  if (!start_selection_handle_)
+    start_selection_handle_.reset(new TouchHandle(this, anchor_orientation_));
+  else
+    start_selection_handle_->SetOrientation(anchor_orientation_);
+
+  if (!end_selection_handle_)
+    end_selection_handle_.reset(new TouchHandle(this, focus_orientation_));
+  else
+    end_selection_handle_->SetOrientation(focus_orientation_);
+
+  if (!is_selection_active_) {
+    is_selection_active_ = true;
+    client_->OnSelectionEvent(SELECTION_SHOWN, GetAnchorPosition());
+  }
+}
+
+void TouchSelectionController::DeactivateSelection() {
+  if (!is_selection_active_)
+    return;
+  DCHECK(start_selection_handle_);
+  DCHECK(end_selection_handle_);
+  start_selection_handle_->Hide();
+  end_selection_handle_->Hide();
+  is_selection_active_ = false;
+  client_->OnSelectionEvent(SELECTION_CLEARED, gfx::PointF());
+}
+
+void TouchSelectionController::ResetCachedValues() {
+  anchor_rect_ = gfx::RectF();
+  focus_rect_ = gfx::RectF();
+  anchor_orientation_ = TOUCH_HANDLE_ORIENTATION_UNDEFINED;
+  focus_orientation_ = TOUCH_HANDLE_ORIENTATION_UNDEFINED;
+  anchor_visible_ = false;
+  focus_visible_ = false;
+  selection_editable_for_last_update_ = false;
+}
+
+gfx::PointF TouchSelectionController::GetAnchorPosition() const {
+  return anchor_rect_.bottom_left();
+}
+
+gfx::PointF TouchSelectionController::GetFocusPosition() const {
+  return focus_rect_.bottom_left();
+}
+
+float TouchSelectionController::GetAnchorLineHeight() const {
+  return anchor_rect_.height();
+}
+
+float TouchSelectionController::GetFocusLineHeight() const {
+  return focus_rect_.height();
+}
+
+}  // namespace content