Make the Translate Overflow Menu using ListPopupWindow

chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateMenuHelper.java

Index: chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateMenuHelper.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateMenuHelper.java b/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateMenuHelper.java
new file mode 100644
index 0000000000000000000000000000000000000000..958ac111a9287840a17452e1b3e9040d77dc243f
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+++ b/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateMenuHelper.java
@@ -0,0 +1,238 @@
+// 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.chrome.browser.infobar.translate;
+
+import android.content.Context;
+import android.support.v4.content.ContextCompat;
+import android.view.ContextThemeWrapper;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.AdapterView;
+import android.widget.ArrayAdapter;
+import android.widget.ListPopupWindow;
+import android.widget.PopupWindow;
+import android.widget.TextView;
+
+import org.chromium.chrome.R;
+
+import java.util.List;
+
+/**
+ * A Helper class for managing the Translate Overflow Menu.
+ */
+public class TranslateMenuHelper implements AdapterView.OnItemClickListener {
+    private static final String EMPTY_STRING = "";
+    private final TranslateMenuItemListener mItemListener;
+    private ContextThemeWrapper mWrapper;
+    private View mAnchorView;
+    private TranslateMenuAdapter mAdapter;
+    private ListPopupWindow mPopup;
+
+    /**
+     * Add a divider menu item to list.
+     * @param list The list of items to show in the menu.
+     */
+    public static void addDivider(List<TranslateMenuElement> list) {
+        list.add(new TranslateMenuElement(
+                EMPTY_STRING, EMPTY_STRING, TranslateMenuAdapter.MENU_DIVIDER));
+    }
+
+    /**
+     * Add an overflow menu item to list.
+     * @param title Title of the menu item
+     * @param code  Code of the menu item

[Marti Wong, 2017/04/12 02:13:42]

change the name from id to code after discussing with Leo.  "code" makes more
sense in our case.

+     * @param list  The list of items to show in the menu.
+     */
+    public static void addOverflowMenuItem(
+            String title, String code, List<TranslateMenuElement> list) {
+        list.add(new TranslateMenuElement(title, code, TranslateMenuAdapter.OVERFLOW_MENU_ITEM));
+    }
+
+    /**
+     * Add a source language menu item to list.
+     * @param title Title of the language
+     * @param code  ISO code of the language
+     * @param list  The list of items to show in the menu.
+     */
+    public static void addSourceLanguageMenuItem(

[Marti Wong, 2017/04/12 02:13:42]

after discussing to Leo, I divided LANGUAGE_MENU_ITEM into
SOURCE_LANGUAGE_MENU_ITEM and TARGET_LANGUAGE_MENU_ITEM so that callback
function can distinguished between 2 and act accordingly.

+            String title, String code, List<TranslateMenuElement> list) {
+        list.add(new TranslateMenuElement(
+                title, code, TranslateMenuAdapter.SOURCE_LANGUAGE_MENU_ITEM));
+    }
+
+    /**
+     * Add a target language menu item to list.
+     * @param title Title of the language
+     * @param code  ISO code of the language
+     * @param list  The list of items to show in the menu.
+     */
+    public static void addTargetLanguageMenuItem(
+            String title, String code, List<TranslateMenuElement> list) {
+        list.add(new TranslateMenuElement(
+                title, code, TranslateMenuAdapter.TARGET_LANGUAGE_MENU_ITEM));
+    }
+
+    /**
+     * Interface for receiving the click event of menu item.
+     */
+    public interface TranslateMenuItemListener {
+        // return true if the menu is dismissed after clicking on the item;  return false otherwise.
+        // (when clicking on 'More languages' or 'Page not in this language', we show the language
+        // menu by keeping the menu but replace the items inside.)
+        boolean onTranslateMenuItemClicked(String code, int type);
+    }
+
+    public TranslateMenuHelper(
+            Context context, View anchorView, TranslateMenuItemListener itemListener) {
+        mWrapper = new ContextThemeWrapper(context, R.style.OverflowMenuTheme);
+        mAnchorView = anchorView;
+        mItemListener = itemListener;
+    }
+
+    /**
+     * Show the overflow menu.
+     * @param list List of menuitems.
+     */
+    public void show(List<TranslateMenuElement> list) {
+        if (mPopup == null) {
+            mPopup = new ListPopupWindow(mWrapper, null, android.R.attr.popupMenuStyle);
+            mPopup.setModal(true);
+            mPopup.setAnchorView(mAnchorView);
+            mPopup.setInputMethodMode(PopupWindow.INPUT_METHOD_NOT_NEEDED);
+
+            // Need to explicitly set the background here.  Relying on it being set in the style
+            // caused an incorrectly drawn background.
+            mPopup.setBackgroundDrawable(
+                    ContextCompat.getDrawable(mWrapper, R.drawable.edge_menu_bg));
+
+            int popupWidth = mWrapper.getResources().getDimensionPixelSize(
+                    R.dimen.infobar_translate_menu_width);
+            mPopup.setWidth(popupWidth);
+
+            mAdapter = new TranslateMenuAdapter(
+                    mWrapper, R.id.menu_item_text, list, LayoutInflater.from(mWrapper));
+            mPopup.setAdapter(mAdapter);
+
+            mPopup.setOnItemClickListener(this);
+        } else {
+            mAdapter.clear();
+            mAdapter.addAll(list);
+        }
+
+        if (!mPopup.isShowing()) {
+            mPopup.show();
+            mPopup.getListView().setItemsCanFocus(true);
+        }
+    }
+
+    @Override
+    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
+        if (mItemListener.onTranslateMenuItemClicked(
+                    mAdapter.getItem(position).getCode(), mAdapter.getItemViewType(position))) {
+            dismiss();
+        }
+    }
+
+    /**
+     * Dismisses the app menu.
+     */
+    void dismiss() {
+        if (isShowing()) {
+            mPopup.dismiss();
+        }
+    }
+
+    /**
+     * @return Whether the app menu is currently showing.
+     */
+    boolean isShowing() {
+        if (mPopup == null) {
+            return false;
+        }
+        return mPopup.isShowing();
+    }
+
+    /**
+     * The provides the views of the menu items and dividers.
+     */
+    public static final class TranslateMenuAdapter extends ArrayAdapter<TranslateMenuElement> {
+        public static final int MENU_DIVIDER = 0;
+        public static final int OVERFLOW_MENU_ITEM = 1;
+        public static final int SOURCE_LANGUAGE_MENU_ITEM = 2;
+        public static final int TARGET_LANGUAGE_MENU_ITEM = 3;
+        // TODO(martiw) create OVERFLOW_MENU_ITEM_WITH_CHECKBOX_CHECKED and
+        // OVERFLOW_MENU_ITEM_WITH_CHECKBOX_UNCHECKED for "Always Translate Language"
+
+        LayoutInflater mInflater;
+
+        public TranslateMenuAdapter(Context context, int textViewResourceId,
+                List<TranslateMenuElement> items, LayoutInflater inflater) {
+            super(context, textViewResourceId, items);
+            mInflater = inflater;
+        }
+
+        @Override
+        public int getItemViewType(int position) {
+            return getItem(position).getType();
+        }
+
+        @Override
+        public boolean isEnabled(int position) {
+            return getItemViewType(position) != MENU_DIVIDER;
+        }
+
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            switch (getItemViewType(position)) {
+                case MENU_DIVIDER:
+                    convertView = mInflater.inflate(R.layout.translate_menu_divider, parent, false);
+                    break;
+                case OVERFLOW_MENU_ITEM:
+                case SOURCE_LANGUAGE_MENU_ITEM:
+                case TARGET_LANGUAGE_MENU_ITEM:
+                    convertView = mInflater.inflate(R.layout.translate_menu_item, parent, false);
+                    ((TextView) convertView.findViewById(R.id.menu_item_text))
+                            .setText(getItem(position).toString());
+                    break;
+                // TODO(martiw) create the layout for OVERFLOW_MENU_ITEM_WITH_CHECKBOX_CHECKED and
+                // OVERFLOW_MENU_ITEM_WITH_CHECKBOX_UNCHECKED for "Always Translate Language"
+                default:
+                    assert false : "Unexpected MenuItem type";
+            }
+            return convertView;
+        }
+    }
+
+    /**
+     * The element that goes inside the menu.
+     */
+    public static final class TranslateMenuElement {
+        private final String mTitle;
+        private final String mCode;
+        private final int mType;
+
+        public TranslateMenuElement(String title, String code, int type) {
+            mTitle = title;
+            mCode = code;
+            mType = type;
+        }
+
+        public String getCode() {
+            return mCode;
+        }
+
+        public int getType() {
+            return mType;
+        }
+
+        /**
+         * This is the text displayed in the menu item.
+         */
+        public String toString() {
+            return mTitle;
+        }
+    }
+}