Redesign sign in and sign in confirmation screens for Narnia 2.0

chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninConfirmationView.java

+// 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.
+
+package org.chromium.chrome.browser.signin;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.widget.LinearLayout;
+import android.widget.RelativeLayout;
+import android.widget.ScrollView;
+
+import org.chromium.chrome.R;
+
+/**
+* This view allows the user to confirm signed in account, sync, and service personalization.
+*/
+public class AccountSigninConfirmationView extends ScrollView {
+    private Observer mObserver;
+    private boolean mScrolledToBottom = false;
+
+    /**
+    * Scrolled to bottom observer.
+    */
+    public interface Observer {
+        /**
+        * On scrolled to bottom. This is called only once when showing the view.
+        */
+        void onScrolledToBottom();
+    }
+
+    public AccountSigninConfirmationView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        // This assumes that view's layout_width and layout_height are set to match_parent.
+        assert MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.EXACTLY;
+        assert MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.EXACTLY;
+
+        int width = MeasureSpec.getSize(widthMeasureSpec);
+        int height = MeasureSpec.getSize(heightMeasureSpec);
+
+        // Sets aspect ratio of the head to 16:9.
+        if (height > width) {
+            LinearLayout layout = (LinearLayout) findViewById(R.id.signin_confirmation_head);
+            RelativeLayout.LayoutParams params =
+                    (RelativeLayout.LayoutParams) layout.getLayoutParams();
+            params.height = width * 9 / 16;
+            params.width = LayoutParams.MATCH_PARENT;
+            layout.setLayoutParams(params);
+        }
+
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+    }
+
+    @Override
+    protected float getTopFadingEdgeStrength() {
+        // Disable fading out effect at the top of this ScrollView.
+        return 0;
+    }
+
+    @Override
+    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+        super.onLayout(changed, left, top, right, bottom);
+
+        notifyIfScrolledToBottom(true);
+    }
+
+    @Override
+    protected void onScrollChanged(int l, int t, int oldl, int oldt) {
+        super.onScrollChanged(l, t, oldl, oldt);
+
+        notifyIfScrolledToBottom(false);
+    }
+
+    /**
+     * Sets scrolled to bottom observer. See {@link Observer}
+     *
+     * @param observer The observer.
+     */
+    public void setScrolledToBottomObserver(Observer observer) {
+        mObserver = observer;
+    }
+
+    private void notifyIfScrolledToBottom(boolean forceNotify) {
+        if (mObserver == null) return;
+
+        if (!forceNotify && mScrolledToBottom) return;
+
+        int distance = (getChildAt(getChildCount() - 1).getBottom() - (getHeight() + getScrollY()));
+        if (distance <= findViewById(R.id.signin_settings_control).getPaddingBottom()) {
+            mObserver.onScrolledToBottom();
+            mScrolledToBottom = true;
+        } else {
+            mScrolledToBottom = false;
+        }
+    }
+}