Update Download Home FilterCoordinator.

- Move FilterModel to FilterProperties.
- Incorporate showing/hiding the tabs as a new property on the model.

Change-Id: I0711ab244aada2ee27d8693408551261911df41e
Reviewed-on: https://chromium-review.googlesource.com/1149268
Commit-Queue: Shakti Sahu <shaktisahu@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579386}

chrome/android/java/src/org/chromium/chrome/browser/download/home/filter/FilterCoordinator.java

@@ -11,6 +11,8 @@ import android.view.View;
 import org.chromium.base.ObserverList;
 import org.chromium.chrome.browser.download.home.filter.Filters.FilterType;
 import org.chromium.chrome.browser.download.home.filter.chips.ChipsCoordinator;
+import org.chromium.chrome.browser.modelutil.PropertyKey;
+import org.chromium.chrome.browser.modelutil.PropertyModel;
 import org.chromium.chrome.browser.modelutil.PropertyModelChangeProcessor;
 
 import java.lang.annotation.Retention;
@@ -32,15 +34,12 @@ public class FilterCoordinator {
     }
 
     private final ObserverList<Observer> mObserverList = new ObserverList<>();
-    private FilterModel mModel;
-    private FilterViewBinder mViewBinder;
-    private FilterView mView;
+    private final PropertyModel mModel;
+    private final FilterViewBinder mViewBinder;
+    private final FilterView mView;
 
-    private ChipsCoordinator mChipsCoordinator;
-    private FilterChipsProvider mChipsProvider;
-
-    /** No-args constructor to be used by subclasses. */
-    protected FilterCoordinator() {}
+    private final ChipsCoordinator mChipsCoordinator;
+    private final FilterChipsProvider mChipsProvider;
 
     /**
      * Builds a new FilterCoordinator.
@@ -50,13 +49,18 @@ public class FilterCoordinator {
         mChipsProvider = new FilterChipsProvider(type -> handleChipSelected(), chipFilterSource);
         mChipsCoordinator = new ChipsCoordinator(context, mChipsProvider);
 
-        mModel = new FilterModel();
+        mModel = new PropertyModel(FilterProperties.ALL_KEYS);
         mViewBinder = new FilterViewBinder();
         mView = new FilterView(context);
-        mModel.addObserver(new PropertyModelChangeProcessor<>(mModel, mView, mViewBinder));
+        mModel.addObserver(new PropertyModelChangeProcessor<PropertyModel, FilterView, PropertyKey>(
+                mModel, mView, mViewBinder));
 
-        mModel.setChangeListener(selectedTab -> handleTabSelected(selectedTab));
+        mModel.setValue(
+                FilterProperties.CHANGE_LISTENER, selectedTab -> handleTabSelected(selectedTab));
         selectTab(TabType.FILES);
+
+        // TODO(shaktisahu): Check if prefetch UI is enabled.
+        mModel.setValue(FilterProperties.SHOW_TABS, true);
     }
 
     /** @return The {@link View} representing this widget. */
@@ -88,12 +92,12 @@ public class FilterCoordinator {
     }
 
     private void selectTab(@TabType int selectedTab) {
-        mModel.setSelectedTab(selectedTab);
+        mModel.setValue(FilterProperties.SELECTED_TAB, selectedTab);
 
         if (selectedTab == TabType.FILES) {
-            mModel.setContentView(mChipsCoordinator.getView());
+            mModel.setValue(FilterProperties.CONTENT_VIEW, mChipsCoordinator.getView());
         } else if (selectedTab == TabType.PREFETCH) {
-            mModel.setContentView(null);
+            mModel.setValue(FilterProperties.CONTENT_VIEW, null);
         }
     }
 
@@ -111,11 +115,11 @@ public class FilterCoordinator {
         notifyFilterChanged(filterType);
     }
 
-    protected void notifyFilterChanged(@FilterType int filter) {
+    private void notifyFilterChanged(@FilterType int filter) {
         for (Observer observer : mObserverList) observer.onFilterChanged(filter);
     }
 
     private void handleChipSelected() {
-        handleTabSelected(mModel.getSelectedTab());
+        handleTabSelected(mModel.getValue(FilterProperties.SELECTED_TAB));
     }
 }
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/download/home/filter/FilterCoordinatorWithNoTabs.java

-// Copyright 2018 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.download.home.filter;
-
-import android.content.Context;
-import android.view.View;
-
-import org.chromium.chrome.browser.download.home.filter.chips.ChipsCoordinator;
-
-/**
- * An empty version of {@code FilterCoordinator} that doesn't contain any tabs.
- */
-
-public class FilterCoordinatorWithNoTabs extends FilterCoordinator {
-    private final ChipsCoordinator mChipsCoordinator;
-    private final FilterChipsProvider mChipsProvider;
-
-    public FilterCoordinatorWithNoTabs(Context context, OfflineItemFilterSource chipFilterSource) {
-        mChipsProvider = new FilterChipsProvider(type -> handleChipSelected(), chipFilterSource);
-        mChipsCoordinator = new ChipsCoordinator(context, mChipsProvider);
-    }
-
-    @Override
-    public View getView() {
-        return mChipsCoordinator.getView();
-    }
-
-    @Override
-    public void setSelectedFilter(int filter) {
-        mChipsProvider.setFilterSelected(filter);
-    }
-
-    private void handleChipSelected() {
-        notifyFilterChanged(mChipsProvider.getSelectedFilter());
-    }
-}

chrome/android/java/src/org/chromium/chrome/browser/download/home/filter/FilterModel.java

-// Copyright 2018 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.download.home.filter;
-
-import android.view.View;
-
-import org.chromium.base.Callback;
-import org.chromium.chrome.browser.download.home.filter.FilterCoordinator.TabType;
-import org.chromium.chrome.browser.modelutil.PropertyObservable;
-
-/**
- * The model responsible for maintaining the visual state of the tab content filter widget.  It also
- * holds callbacks meant to be notified when the tab selection changes.
- */
-class FilterModel extends PropertyObservable<FilterModel.PropertyKey> {
-    static class PropertyKey {
-        static final PropertyKey CONTENT_VIEW = new PropertyKey();
-        static final PropertyKey SELECTED_TAB = new PropertyKey();
-        static final PropertyKey CHANGE_LISTENER = new PropertyKey();
-
-        private PropertyKey() {}
-    }
-
-    private View mContentView;
-    private @TabType int mSelectedTab;
-    private Callback</* @TabType */ Integer> mChangeListener;
-
-    /** Sets {@code contentView} as the {@link View} to be shown in the content area. */
-    public void setContentView(View contentView) {
-        if (mContentView == contentView) return;
-        mContentView = contentView;
-        notifyPropertyChanged(PropertyKey.CONTENT_VIEW);
-    }
-
-    /** Sets which tab should be selected. */
-    public void setSelectedTab(@TabType int selectedTab) {
-        // Note: This does not early-out if selectedTab is the same as mSelectedTab.  This is
-        // because default values might prevent us from pushing valid state and causing the UI to
-        // refresh.
-        mSelectedTab = selectedTab;
-        notifyPropertyChanged(PropertyKey.SELECTED_TAB);
-    }
-
-    /** Sets the {@link Callback} to call when a tab is selected. */
-    public void setChangeListener(Callback</* @TabType */ Integer> changeListener) {
-        if (mChangeListener == changeListener) return;
-        mChangeListener = changeListener;
-        notifyPropertyChanged(PropertyKey.CHANGE_LISTENER);
-    }
-
-    /** @return The {@link View} to use in the content area of the tab selection. */
-    public View getContentView() {
-        return mContentView;
-    }
-
-    /** @return The selected tab type. */
-    public @TabType int getSelectedTab() {
-        return mSelectedTab;
-    }
-
-    /** @return The {@link Callback} to call when a tab is selected. */
-    public Callback</* @TabType */ Integer> getChangeListener() {
-        return mChangeListener;
-    }
-}
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/download/home/filter/FilterProperties.java

+// Copyright 2018 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.download.home.filter;
+
+import android.view.View;
+
+import org.chromium.base.Callback;
+import org.chromium.chrome.browser.modelutil.PropertyKey;
+import org.chromium.chrome.browser.modelutil.PropertyModel.BooleanPropertyKey;
+import org.chromium.chrome.browser.modelutil.PropertyModel.IntPropertyKey;
+import org.chromium.chrome.browser.modelutil.PropertyModel.ObjectPropertyKey;
+
+/** The properties needed to render the download home filter view. */
+public interface FilterProperties {
+    /** The {@link View} to show in the content area. */
+    public static final ObjectPropertyKey<View> CONTENT_VIEW = new ObjectPropertyKey<>();
+
+    /** Which {@code TabType} should be selected. */
+    public static final IntPropertyKey SELECTED_TAB = new IntPropertyKey();
+
+    /** The callback listener for {@code TabType} selection changes. */
+    public static final ObjectPropertyKey<Callback</* @TabType */ Integer>> CHANGE_LISTENER =
+            new ObjectPropertyKey<>();
+
+    /** Whether or not to show the tabs or just show the content. */
+    public static final BooleanPropertyKey SHOW_TABS = new BooleanPropertyKey();
+
+    public static final PropertyKey[] ALL_KEYS =
+            new PropertyKey[] {CONTENT_VIEW, SELECTED_TAB, CHANGE_LISTENER, SHOW_TABS};
+}
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/download/home/filter/FilterView.java

@@ -79,4 +79,9 @@ class FilterView {
     public void setTabSelectedCallback(Callback</* @TabType */ Integer> callback) {
         mTabSelectedCallback = callback;
     }
+
+    /** Sets whether or not we show the tabs. */
+    public void setShowTabs(boolean show) {
+        mTabsView.setVisibility(show ? View.VISIBLE : View.GONE);
+    }
 }
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/download/home/filter/FilterViewBinder.java

@@ -4,22 +4,25 @@
 
 package org.chromium.chrome.browser.download.home.filter;
 
-import org.chromium.chrome.browser.download.home.filter.FilterModel.PropertyKey;
+import org.chromium.chrome.browser.modelutil.PropertyKey;
+import org.chromium.chrome.browser.modelutil.PropertyModel;
 import org.chromium.chrome.browser.modelutil.PropertyModelChangeProcessor.ViewBinder;
 
 /**
- * A helper {@link ViewBinder} responsible for gluing {@link FilterModel} to
+ * A helper {@link ViewBinder} responsible for gluing {@link FilterProperties} to
  * {@link FilterView}.
  */
-class FilterViewBinder implements ViewBinder<FilterModel, FilterView, FilterModel.PropertyKey> {
+class FilterViewBinder implements ViewBinder<PropertyModel, FilterView, PropertyKey> {
     @Override
-    public void bind(FilterModel model, FilterView view, PropertyKey propertyKey) {
-        if (propertyKey == FilterModel.PropertyKey.CONTENT_VIEW) {
-            view.setContentView(model.getContentView());
-        } else if (propertyKey == FilterModel.PropertyKey.SELECTED_TAB) {
-            view.setTabSelected(model.getSelectedTab());
-        } else if (propertyKey == FilterModel.PropertyKey.CHANGE_LISTENER) {
-            view.setTabSelectedCallback(model.getChangeListener());
+    public void bind(PropertyModel model, FilterView view, PropertyKey propertyKey) {
+        if (propertyKey == FilterProperties.CONTENT_VIEW) {
+            view.setContentView(model.getValue(FilterProperties.CONTENT_VIEW));
+        } else if (propertyKey == FilterProperties.SELECTED_TAB) {
+            view.setTabSelected(model.getValue(FilterProperties.SELECTED_TAB));
+        } else if (propertyKey == FilterProperties.CHANGE_LISTENER) {
+            view.setTabSelectedCallback(model.getValue(FilterProperties.CHANGE_LISTENER));
+        } else if (propertyKey == FilterProperties.SHOW_TABS) {
+            view.setShowTabs(model.getValue(FilterProperties.SHOW_TABS));
         }
     }
 }
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/download/home/list/DateOrderedListCoordinator.java

@@ -9,7 +9,6 @@ import android.view.View;
 
 import org.chromium.base.Callback;
 import org.chromium.chrome.browser.download.home.filter.FilterCoordinator;
-import org.chromium.chrome.browser.download.home.filter.FilterCoordinatorWithNoTabs;
 import org.chromium.chrome.browser.download.home.filter.Filters.FilterType;
 import org.chromium.chrome.browser.download.home.list.ListItem.ViewListItem;
 import org.chromium.chrome.browser.widget.selection.SelectionDelegate;
@@ -69,9 +68,7 @@ public class DateOrderedListCoordinator {
                 offTheRecord, provider, deleteController, selectionDelegate, model);
 
         // Hook up the FilterCoordinator with our mediator.
-        mFilterCoordinator = shouldShowPrefetchTab()
-                ? new FilterCoordinator(context, mMediator.getFilterSource())
-                : new FilterCoordinatorWithNoTabs(context, mMediator.getFilterSource());
+        mFilterCoordinator = new FilterCoordinator(context, mMediator.getFilterSource());
         mFilterCoordinator.addObserver(mMediator::onFilterTypeSelected);
         mFilterCoordinator.addObserver(filterObserver);
 
@@ -105,9 +102,4 @@ public class DateOrderedListCoordinator {
     public void onDeletionRequested(List<ListItem> items) {
         mMediator.onDeletionRequested(items);
     }
-
-    private boolean shouldShowPrefetchTab() {
-        // TODO(shaktisahu): Check if prefetch UI is enabled.
-        return true;
-    }
 }

chrome/android/java_sources.gni

@@ -448,8 +448,7 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/download/home/filter/Filters.java",
   "java/src/org/chromium/chrome/browser/download/home/filter/FilterChipsProvider.java",
   "java/src/org/chromium/chrome/browser/download/home/filter/FilterCoordinator.java",
-  "java/src/org/chromium/chrome/browser/download/home/filter/FilterCoordinatorWithNoTabs.java",
-  "java/src/org/chromium/chrome/browser/download/home/filter/FilterModel.java",
+  "java/src/org/chromium/chrome/browser/download/home/filter/FilterProperties.java",
   "java/src/org/chromium/chrome/browser/download/home/filter/FilterView.java",
   "java/src/org/chromium/chrome/browser/download/home/filter/FilterViewBinder.java",
   "java/src/org/chromium/chrome/browser/download/home/filter/OfflineItemFilter.java",