Use mojo clipboard service for copy/paste toolbar. (#3778)

* Use mojo clipboard service for copy/paste toolbar.

BUG=https://github.com/flutter/flutter/issues/1567

packages/flutter/lib/services.dart

@@ -18,6 +18,7 @@ export 'src/services/activity.dart';
 export 'src/services/app_messages.dart';
 export 'src/services/asset_bundle.dart';
 export 'src/services/binding.dart';
+export 'src/services/clipboard.dart';
 export 'src/services/haptic_feedback.dart';
 export 'src/services/image_cache.dart';
 export 'src/services/image_decoder.dart';

packages/flutter/lib/src/material/text_selection.dart

@@ -2,9 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'dart:async';
 import 'dart:math' as math;
 
 import 'package:flutter/widgets.dart';
+import 'package:flutter/services.dart';
 
 import 'flat_button.dart';
 import 'icon_button.dart';
@@ -32,8 +34,9 @@ class _TextSelectionToolbar extends StatelessWidget {
     }
     items.add(new FlatButton(
       child: new Text('PASTE'),
-      onPressed: delegate.pasteBuffer != null ? _handlePaste : null)
-    );
+      // TODO(mpcomplete): This should probably be grayed-out if there is nothing to paste.
+      onPressed: _handlePaste
+    ));
     if (value.selection.isCollapsed) {
       items.add(new FlatButton(child: new Text('SELECT ALL'), onPressed: _handleSelectAll));
     }
@@ -50,8 +53,7 @@ class _TextSelectionToolbar extends StatelessWidget {
   }
 
   void _handleCut() {
-    InputValue value = this.value;
-    delegate.pasteBuffer = value.selection.textInside(value.text);
+    Clipboard.setClipboardData(new ClipboardData()..text = value.selection.textInside(value.text));
     delegate.inputValue = new InputValue(
       text: value.selection.textBefore(value.text) + value.selection.textAfter(value.text),
       selection: new TextSelection.collapsed(offset: value.selection.start)
@@ -60,7 +62,7 @@ class _TextSelectionToolbar extends StatelessWidget {
   }
 
   void _handleCopy() {
-    delegate.pasteBuffer = value.selection.textInside(value.text);
+    Clipboard.setClipboardData(new ClipboardData()..text = value.selection.textInside(value.text));
     delegate.inputValue = new InputValue(
       text: value.text,
       selection: new TextSelection.collapsed(offset: value.selection.end)
@@ -68,11 +70,15 @@ class _TextSelectionToolbar extends StatelessWidget {
     delegate.hideToolbar();
   }
 
-  void _handlePaste() {
-    delegate.inputValue = new InputValue(
-      text: value.selection.textBefore(value.text) + delegate.pasteBuffer + value.selection.textAfter(value.text),
-      selection: new TextSelection.collapsed(offset: value.selection.start + delegate.pasteBuffer.length)
-    );
+  Future<Null> _handlePaste() async {
+    InputValue value = this.value;  // Snapshot the input before using `await`.
+    ClipboardData clip = await Clipboard.getClipboardData(Clipboard.kTextPlain);
+    if (clip != null) {
+      delegate.inputValue = new InputValue(
+        text: value.selection.textBefore(value.text) + clip.text + value.selection.textAfter(value.text),
+        selection: new TextSelection.collapsed(offset: value.selection.start + clip.text.length)
+      );
+    }
     delegate.hideToolbar();
   }
 

packages/flutter/lib/src/services/clipboard.dart

@@ -0,0 +1,35 @@
+// Copyright 2016 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 'dart:async';
+
+import 'package:sky_services/editing/editing.mojom.dart' as mojom;
+
+import 'shell.dart';
+
+export 'package:sky_services/editing/editing.mojom.dart' show ClipboardData;
+
+mojom.ClipboardProxy _initClipboardProxy() {
+  mojom.ClipboardProxy proxy = new mojom.ClipboardProxy.unbound();
+  shell.connectToService('mojo:clipboard', proxy);
+  return proxy;
+}
+
+final mojom.ClipboardProxy _clipboardProxy = _initClipboardProxy();
+
+/// An interface to the system's clipboard. Wraps the mojo interface.
+class Clipboard {
+  /// Constants for common [getClipboardData] [format] types.
+  static final String kTextPlain = 'text/plain';
+
+  Clipboard._();
+
+  static void setClipboardData(mojom.ClipboardData clip) {
+    _clipboardProxy.ptr.setClipboardData(clip);
+  }
+
+  static Future<mojom.ClipboardData> getClipboardData(String format) async {
+    return (await _clipboardProxy.ptr.getClipboardData(format)).clip;
+  }
+}

packages/flutter/lib/src/widgets/text_selection.dart

@@ -42,19 +42,10 @@ abstract class TextSelectionDelegate {
   /// Sets the current text input (replaces the whole line).
   void set inputValue(InputValue value);
 
-  /// The copy/paste buffer. Application-wide.
-  String get pasteBuffer;
-
-  /// Sets the copy/paste buffer.
-  void set pasteBuffer(String value);
-
   /// Hides the text selection toolbar.
   void hideToolbar();
 }
 
-// TODO(mpcomplete): need to interact with the system clipboard.
-String _pasteBuffer;
-
 /// Manages a pair of text selection handles to be shown in an Overlay
 /// containing the owning widget.
 class TextSelectionOverlay implements TextSelectionDelegate {
@@ -162,14 +153,6 @@ class TextSelectionOverlay implements TextSelectionDelegate {
       onSelectionOverlayChanged(value);
   }
 
-  @override
-  String get pasteBuffer => _pasteBuffer;
-
-  @override
-  void set pasteBuffer(String value) {
-    _pasteBuffer = value;
-  }
-
   @override
   void hideToolbar() {
     hide();

packages/flutter/test/widget/input_test.dart

@@ -26,9 +26,25 @@ class MockKeyboard implements mojom.Keyboard {
   void setEditingState(mojom.EditingState state) {}
 }
 
+class MockClipboard implements mojom.Clipboard {
+  mojom.ClipboardData _clip;
+
+  @override
+  void setClipboardData(mojom.ClipboardData clip) {
+    _clip = clip;
+  }
+
+  @override
+  dynamic getClipboardData(String format,[Function responseFactory = null]) {
+    return new mojom.ClipboardGetClipboardDataResponseParams()..clip = _clip;
+  }
+}
+
 void main() {
   MockKeyboard mockKeyboard = new MockKeyboard();
   serviceMocker.registerMockService(mojom.Keyboard.serviceName, mockKeyboard);
+  MockClipboard mockClipboard = new MockClipboard();
+  serviceMocker.registerMockService(mojom.Clipboard.serviceName, mockClipboard);
 
   void enterText(String testValue) {
     // Simulate entry of text through the keyboard.