Implement a basic IME-aware input element

This CL introduces a new keyboard service that understands Android IME and
starts work on a Input component that interacts with this service to provide an
editing control.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/995613002

apk/demo/BUILD.gn

@@ -18,6 +18,8 @@ android_library("java") {
     "//base:base_java",
     "//mojo/public/java:bindings",
     "//mojo/public/java:system",
+    "//sky/services/keyboard",
+    "//sky/services/keyboard:interfaces_java",
     "//sky/services/sensors",
     "//sky/services/sensors:interfaces_java",
     "//sky/shell:java",

apk/demo/org/domokit/sky/demo/SkyDemoApplication.java

@@ -8,7 +8,9 @@ import android.content.Context;
 
 import org.chromium.mojo.system.Core;
 import org.chromium.mojo.system.MessagePipeHandle;
+import org.chromium.mojom.keyboard.KeyboardService;
 import org.chromium.mojom.sensors.SensorService;
+import org.domokit.keyboard.KeyboardServiceImpl;
 import org.domokit.sensors.SensorServiceImpl;
 import org.domokit.sky.shell.ServiceFactory;
 import org.domokit.sky.shell.ServiceRegistry;
@@ -28,5 +30,12 @@ public class SkyDemoApplication extends SkyApplication {
                 new SensorServiceImpl(context, core, pipe);
             }
         });
+
+        ServiceRegistry.SHARED.register(KeyboardService.MANAGER.getName(), new ServiceFactory() {
+            @Override
+            public void connectToService(Context context, Core core, MessagePipeHandle pipe) {
+                new KeyboardServiceImpl(context, core, pipe);
+            }
+        });
     }
 }

examples/editor/editor_app.dart

+// Copyright 2015 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 '../../framework/fn.dart';
+import 'input.dart';
+
+class EditorApp extends App {
+  Node build() {
+    return new Input();
+  }
+}

examples/editor/index.sky

+#!mojo mojo:sky_viewer
+<sky>
+<import src="/sky/framework/debug/shake-to-reload.sky" />
+<script>
+import 'editor_app.dart';
+main() {
+  new EditorApp();
+}
+</script>
+</sky>

examples/editor/input.dart

+// Copyright 2015 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 '../../framework/fn.dart';
+import '../../framework/shell.dart' as shell;
+import 'package:sky/services/keyboard/keyboard.mojom.dart';
+import 'dart:math';
+
+class Input extends Component implements KeyboardClient{
+  static Style _style = new Style('''
+    display: paragraph;
+    padding: 10px;
+    height: 200px;
+    background-color: lightblue;'''
+  );
+
+  static Style _composingStyle = new Style('''
+    display: inline;
+    text-decoration: underline;'''
+  );
+
+  KeyboardServiceProxy _service;
+  KeyboardClientStub _stub;
+
+  String _text = "";
+  int _composingStart = -1;
+  int _composingEnd = -1;
+
+  Input({Object key}) : super(key: key, stateful: true) {
+    events.listen('click', _handleClick);
+    _stub = new KeyboardClientStub.unbound()..impl = this;
+  }
+
+  bool get _hasComposingRegion => _composingStart != -1 && _composingEnd != -1;
+
+  void _handleClick(_) {
+    if (_service != null)
+      return;
+    _service = new KeyboardServiceProxy.unbound();
+    shell.requestService(_service);
+    _service.ptr.show(_stub);
+  }
+
+  void _replaceComposing(String text) {
+    if (!_hasComposingRegion) {
+      _composingStart = _text.length;
+      _composingEnd = _composingStart + text.length;
+      _text += text;
+      return;
+    }
+
+    _text = _text.substring(0, _composingStart)
+        + text + _text.substring(_composingEnd);
+    _composingEnd = _composingStart + text.length;
+  }
+
+  void _clearComposingRegion() {
+    _composingStart = -1;
+    _composingEnd = -1;
+  }
+
+  void commitText(String text, int newCursorPosition) {
+    setState(() {
+      _replaceComposing(text);
+      _clearComposingRegion();
+    });
+  }
+
+  void setComposingText(String text, int newCursorPosition) {
+    setState(() {
+      _replaceComposing(text);
+    });
+  }
+
+  void setComposingRegion(int start, int end) {
+    setState(() {
+      _composingStart = start;
+      _composingEnd = end;
+    });
+  }
+
+  Node build() {
+    List<Node> children = new List<Node>();
+
+    if (!_hasComposingRegion) {
+      children.add(new Text(_text));
+    } else {
+      String run = _text.substring(0, _composingStart);
+      if (!run.isEmpty)
+        children.add(new Text(run));
+
+      run = _text.substring(_composingStart, _composingEnd);
+      if (!run.isEmpty) {
+        children.add(new Container(
+          style: _composingStyle,
+          children: [new Text(_text.substring(_composingStart, _composingEnd))]
+        ));
+      }
+
+      run = _text.substring(_composingEnd);
+      if (!run.isEmpty)
+        children.add(new Text(_text.substring(_composingEnd)));
+    }
+
+    return new Container(
+      style: _style,
+      children: children
+    );
+  }
+}

services/keyboard/BUILD.gn

+# Copyright 2015 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("//build/config/android/config.gni")
+import("//build/config/android/rules.gni")
+import("//mojo/public/tools/bindings/mojom.gni")
+
+android_library("keyboard") {
+  java_files = [
+    "org/domokit/keyboard/InputConnectionAdaptor.java",
+    "org/domokit/keyboard/KeyboardServiceImpl.java",
+  ]
+
+  deps = [
+    "//mojo/public/java:bindings",
+    "//mojo/public/java:system",
+    ":interfaces_java",
+  ]
+}
+
+mojom("interfaces") {
+  sources = [
+    "keyboard.mojom",
+  ]
+}

services/keyboard/keyboard.mojom

+// Copyright 2015 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.
+
+module keyboard;
+
+interface KeyboardClient {
+  commitText(string text, int32 newCursorPosition);
+  setComposingText(string text, int32 newCursorPosition);
+  setComposingRegion(int32 start, int32 end);
+};
+
+interface KeyboardService {
+  Show(KeyboardClient client);
+  Hide();
+};

services/keyboard/org/domokit/keyboard/InputConnectionAdaptor.java

+// Copyright 2015 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.
+
+package org.domokit.keyboard;
+
+import android.text.InputType;
+import android.view.View;
+import android.view.inputmethod.BaseInputConnection;
+import android.view.inputmethod.EditorInfo;
+
+import org.chromium.mojom.keyboard.KeyboardClient;
+
+/**
+ * An adaptor between InputConnection and KeyboardClient.
+ */
+public class InputConnectionAdaptor extends BaseInputConnection {
+    private KeyboardClient mClient;
+
+    public InputConnectionAdaptor(View view, KeyboardClient client, EditorInfo outAttrs) {
+        super(view, true);
+        assert client != null;
+        mClient = client;
+        outAttrs.inputType = InputType.TYPE_CLASS_TEXT;
+        outAttrs.initialSelStart = -1;
+        outAttrs.initialSelEnd = -1;
+    }
+
+    @Override
+    public boolean commitText(CharSequence text, int newCursorPosition) {
+        mClient.commitText(text.toString(), newCursorPosition);
+        return super.commitText(text, newCursorPosition);
+    }
+
+    @Override
+    public boolean setComposingText(CharSequence text, int newCursorPosition) {
+        mClient.setComposingText(text.toString(), newCursorPosition);
+        return super.setComposingText(text, newCursorPosition);
+    }
+
+    @Override
+    public boolean setComposingRegion(int start, int end) {
+        mClient.setComposingRegion(start, end);
+        return super.setComposingRegion(start, end);
+    }
+}

services/keyboard/org/domokit/keyboard/KeyboardServiceImpl.java

+// Copyright 2015 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.
+
+package org.domokit.keyboard;
+
+import android.content.Context;
+import android.view.View;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputConnection;
+import android.view.inputmethod.InputMethodManager;
+
+import org.chromium.mojo.system.Core;
+import org.chromium.mojo.system.MessagePipeHandle;
+import org.chromium.mojo.system.MojoException;
+import org.chromium.mojom.keyboard.KeyboardClient;
+import org.chromium.mojom.keyboard.KeyboardService;
+
+/**
+ * Android implementation of Keyboard.
+ */
+public class KeyboardServiceImpl implements KeyboardService {
+    private static View sActiveView;
+    private static KeyboardClient sActiveClient;
+
+    private Context mContext;
+
+    public KeyboardServiceImpl(Context context, Core core, MessagePipeHandle pipe) {
+        mContext = context;
+
+        KeyboardService.MANAGER.bind(this, pipe);
+    }
+
+    public static void setActiveView(View view) {
+        sActiveView = view;
+    }
+
+    public static InputConnection createInputConnection(EditorInfo outAttrs) {
+        if (sActiveClient == null)
+            return null;
+        return new InputConnectionAdaptor(sActiveView, sActiveClient, outAttrs);
+    }
+
+    @Override
+    public void close() {}
+
+    @Override
+    public void onConnectionError(MojoException e) {}
+
+    @Override
+    public void show(KeyboardClient client) {
+        sActiveClient = client;
+        InputMethodManager imm =
+                (InputMethodManager) mContext.getSystemService(Context.INPUT_METHOD_SERVICE);
+        imm.restartInput(sActiveView);
+        imm.showSoftInput(sActiveView, InputMethodManager.SHOW_IMPLICIT);
+    }
+
+    public void hide() {
+        InputMethodManager imm =
+                (InputMethodManager) mContext.getSystemService(Context.INPUT_METHOD_SERVICE);
+        imm.hideSoftInputFromWindow(sActiveView.getApplicationWindowToken(), 0);
+    }
+}

shell/BUILD.gn

@@ -89,6 +89,7 @@ android_library("java") {
     "//mojo/public/java:bindings",
     "//mojo/public/java:system",
     "//mojo/services/network/public/interfaces:interfaces_java",
+    "//sky/services/keyboard",
     "//sky/services/oknet",
     "//sky/services/viewport:viewport_java",
   ]

shell/org/domokit/sky/shell/PlatformView.java

@@ -10,6 +10,8 @@ import android.view.Surface;
 import android.view.SurfaceHolder;
 import android.view.SurfaceView;
 import android.view.View;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputConnection;
 
 import org.chromium.base.JNINamespace;
 import org.chromium.mojo.bindings.InterfaceRequest;
@@ -21,6 +23,7 @@ import org.chromium.mojom.sky.InputEvent;
 import org.chromium.mojom.sky.PointerData;
 import org.chromium.mojom.sky.PointerKind;
 import org.chromium.mojom.sky.ViewportObserver;
+import org.domokit.keyboard.KeyboardServiceImpl;
 
 /**
  * A view containing Sky
@@ -68,6 +71,7 @@ public class PlatformView extends SurfaceView
         getHolder().addCallback(mSurfaceCallback);
 
         mGestureProvider = new GestureProvider(context, this);
+        KeyboardServiceImpl.setActiveView(this);
     }
 
     @Override
@@ -86,6 +90,16 @@ public class PlatformView extends SurfaceView
         }
     }
 
+    @Override
+    public boolean onCheckIsTextEditor() {
+        return true;
+    }
+
+    @Override
+    public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
+        return KeyboardServiceImpl.createInputConnection(outAttrs);
+    }
+
     private int getTypeForAction(int maskedAction) {
         // Primary pointer:
         if (maskedAction == MotionEvent.ACTION_DOWN)