WebView autofill implementation

components/autofill/android/java/src/org/chromium/components/autofill/AutofillProvider.java

Index: components/autofill/android/java/src/org/chromium/components/autofill/AutofillProvider.java
diff --git a/components/autofill/android/java/src/org/chromium/components/autofill/AutofillProvider.java b/components/autofill/android/java/src/org/chromium/components/autofill/AutofillProvider.java
new file mode 100644
index 0000000000000000000000000000000000000000..ce8a0ea9f5ac9a312b4d4468a0bc7ebb7cd0858e
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+++ b/components/autofill/android/java/src/org/chromium/components/autofill/AutofillProvider.java
@@ -0,0 +1,116 @@
+// 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.
+
+package org.chromium.components.autofill;
+
+import android.util.SparseArray;
+import android.view.ViewStructure;
+
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
+
+/**
+ * This class defines interface of AutofillProvider, it doesn't use chrome's
+ * autofill service or suggestion UI, instead, uses third party autofill service
+ * by knowing of format structure and user's input.
+ *
+ * AutofillProvider handles one autofill session at time, each call of

[sgurun-gerrit only, 2017/04/28 01:46:39]

is this limitation per WebContents? what if there are multiple webviews in the
app.

[Roger McFarlane (Chromium), 2017/04/28 20:28:27]

What is the scope of a session?

How does this work for multi-form pages? Do you handle segmented forms?

On a given page, you might have:

  - a sign-in form at the top
  - a separate guest checkout form asking for contact and/or credit card
    information
      -> these might be seperate forms or they might be the same form
      -> you might have both billing and shipping addresses
  - the form might change dynamically on the page as the user (and
    autofill) are interacting with it.

IIUC, this is driven by the user attempting to autofill in a form (whose
fields are determined by the webview) and represents one fill attempt?
I.e., is this created in response to the user initiating some fill event
for a given set of fields that constitutes a form? Or, is this tied to a
web-contents?

[michaelbai, 2017/04/28 20:52:00]

Yes, It is driven by user, more specifically, A new session will started if the
form is different  among the calling of
AutofillManager::OnQueryFormFieldAutofill() ,  

[michaelbai, 2017/04/28 20:52:00]

Each WebView has its own AutofillProvider, since each WebView is different
custom view, framework should have different session for them.

+ * queryFormFieldAutofill cancels previous session and starts a new one, the
+ * calling of other methods shall associate with current session.
+ */
+@JNINamespace("autofill")
+public abstract class AutofillProvider {
+    private long mNativeAutofillProviderAndroid;
+
+    public AutofillProvider() {}
+
+    public long getNativeAutofillProviderAndroid() {
+        if (mNativeAutofillProviderAndroid == 0) {
+            mNativeAutofillProviderAndroid = nativeCreateNativePeer();
+        }
+        return mNativeAutofillProviderAndroid;
+    }
+
+    /**
+     * Invoked when autofill value is available, AutofillProvider shall fill the
+     * form by provided values.
+     *
+     * @param values the array of autofill values, the key is virtual id of form
+     *            field.
+     */
+    public abstract void autofill(final SparseArray<String> values);
+
+    /**
+     * Invoked when autofill service needs the form structure.
+     *
+     * @param structure see View.onProvideAutofillVirtualStructure()
+     * @param flags
+     */
+    public abstract void onProvideAutoFillVirtualStructure(ViewStructure structure, int flags);
+
+    /**
+     * Invoked when filling form is need. AutofillProvider shall ask autofill
+     * service for the value to fill the form.
+     *
+     * @param formData the form needs to fill.
+     * @param focus the index of focus field in formData
+     * @param x the boundary of focus field.
+     * @param y the boundary of focus field.
+     * @param width the boundary of focus field.
+     * @param height the boundary of focus field.
+     */
+    @CalledByNative
+    protected abstract void queryFormFieldAutofill(
+            FormData formData, int focus, int x, int y, int width, int height);
+
+    /**
+     * Invoked when text field is changed.
+     *
+     * @param index index of field in current form.
+     */
+    @CalledByNative
+    protected abstract void onTextFieldDidChange(int index);
+
+    /**
+     * Invoked when current form will be submitted.
+     */
+    @CalledByNative
+    protected abstract void onWillSubmitForm();
+
+    /**
+     * Invoked when focus field changed.
+     *
+     * @param focusOnForm whether focus is still on form.
+     * @param focusItem the index of field has focus
+     * @param x the boundary of focus field.
+     * @param y the boundary of focus field.
+     * @param width the boundary of focus field.
+     * @param height the boundary of focus field.
+     */
+    @CalledByNative
+    protected abstract void onFocusChanged(
+            boolean focusOnForm, int focusItem, int x, int y, int width, int height);
+
+    /**
+     * Send form to renderer for filling.
+     *
+     * @param formData the form to fill.
+     */
+    protected void autofill(FormData formData) {
+        nativeOnAutofillAvailable(mNativeAutofillProviderAndroid, formData);
+    }
+
+    /**
+     * Invoked when native peer is destroyed.
+     */
+    @CalledByNative
+    private void onNativeDestroyed() {
+        mNativeAutofillProviderAndroid = 0;
+    }
+
+    private native long nativeCreateNativePeer();
+
+    private native void nativeOnAutofillAvailable(
+            long nativeAutofillProviderAndroid, FormData formData);
+}