Upstream oodles of Chrome for Android code into Chromium.

chrome/android/java_staging/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkRecyclerView.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.chromium.chrome.browser.enhancedbookmarks;
+
+import android.content.Context;
+import android.graphics.Rect;
+import android.support.v7.widget.GridLayoutManager;
+import android.support.v7.widget.GridLayoutManager.SpanSizeLookup;
+import android.support.v7.widget.RecyclerView;
+import android.util.AttributeSet;
+import android.view.View;
+import android.widget.Checkable;
+import android.widget.RelativeLayout;
+
+import com.google.android.apps.chrome.R;
+
+import org.chromium.components.bookmarks.BookmarkId;
+
+import java.util.List;
+
+/**
+ * Container for all bookmark items shown in enhanced bookmark manager.
+ */
+public class EnhancedBookmarkRecyclerView extends RecyclerView implements
+        EnhancedBookmarkUIObserver {
+    private static final int MINIMUM_LARGE_TABLET_WIDTH_DP = 720;
+    private static Boolean sIsLargeTablet = null;
+
+    private EnhancedBookmarkDelegate mDelegate;
+    private View mEmptyView;
+    private int mGridMinWidthPx;
+    private int mItemHalfSpacePx;
+    private ItemDecoration mItemDecoration;
+
+    /**
+     * @return True if the current device's minimum dimension is larger than 720dp.
+     */
+    public static boolean isLargeTablet(Context context) {
+        // TODO(ianwen): move this function to DeviceFormFactor.java in upstream.
+        if (sIsLargeTablet == null) {
+            int minimumScreenWidthDp = context.getResources().getConfiguration()
+                    .smallestScreenWidthDp;
+            sIsLargeTablet = minimumScreenWidthDp >= MINIMUM_LARGE_TABLET_WIDTH_DP;
+        }
+        return sIsLargeTablet;
+    }
+
+    /**
+     * Constructs a new instance of enhanced bookmark recycler view.
+     */
+    public EnhancedBookmarkRecyclerView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        // Span count will be dynamically computed in onMeasure().
+        setLayoutManager(new GridLayoutManager(context, 1));
+        mGridMinWidthPx = getResources().getDimensionPixelSize(
+                R.dimen.enhanced_bookmark_min_grid_width);
+        mItemHalfSpacePx = getResources().getDimensionPixelSize(
+                R.dimen.enhanced_bookmark_item_half_space);
+        mItemDecoration = new ItemDecoration() {
+            @Override
+            public void getItemOffsets(Rect outRect, View view, RecyclerView parent, State state) {
+                outRect.set(mItemHalfSpacePx, mItemHalfSpacePx, mItemHalfSpacePx, mItemHalfSpacePx);
+            }
+        };
+        setHasFixedSize(true);
+    }
+
+    @Override
+    protected void onMeasure(int widthSpec, int heightSpec) {
+        super.onMeasure(widthSpec, heightSpec);
+        int width = MeasureSpec.getSize(widthSpec);
+        if (width != 0 && mDelegate != null && !mDelegate.isListModeEnabled()) {
+            int spans = width / mGridMinWidthPx;
+            if (spans > 0) {
+                getLayoutManager().setSpanCount(spans);
+                if (getAdapter() != null) getAdapter().setNumColumns(spans);
+            }
+        }
+    }
+
+    /**
+     * Sets the view to be shown if there are no items in adapter.
+     */
+    public void setEmptyView(View emptyView) {
+        mEmptyView = emptyView;
+    }
+
+    @Override
+    public void setAdapter(final Adapter adapter) {
+        super.setAdapter(adapter);
+        adapter.registerAdapterDataObserver(new AdapterDataObserver() {
+            @Override
+            public void onChanged() {
+                super.onChanged();
+                updateEmptyViewVisibility(adapter);
+            }
+
+            @Override
+            public void onItemRangeInserted(int positionStart, int itemCount) {
+                super.onItemRangeInserted(positionStart, itemCount);
+                updateEmptyViewVisibility(adapter);
+            }
+
+            @Override
+            public void onItemRangeRemoved(int positionStart, int itemCount) {
+                super.onItemRangeRemoved(positionStart, itemCount);
+                updateEmptyViewVisibility(adapter);
+            }
+        });
+        updateEmptyViewVisibility(adapter);
+    }
+
+    @Override
+    public EnhancedBookmarkItemsAdapter getAdapter() {
+        return (EnhancedBookmarkItemsAdapter) super.getAdapter();
+    }
+
+    @Override
+    public GridLayoutManager getLayoutManager() {
+        return (GridLayoutManager) super.getLayoutManager();
+    }
+
+    /**
+     * Unlike ListView or GridView, RecyclerView does not provide default empty
+     * view implementation. We need to check it ourselves.
+     */
+    private void updateEmptyViewVisibility(Adapter adapter) {
+        mEmptyView.setVisibility(adapter.getItemCount() == 0 ? View.VISIBLE : View.GONE);
+    }
+
+    private void setMargin(int marginInPx) {
+        RelativeLayout.LayoutParams lp = (RelativeLayout.LayoutParams) getLayoutParams();
+        lp.setMargins(marginInPx, marginInPx, marginInPx, marginInPx);
+        setLayoutParams(lp);
+    }
+
+    // EnhancedBookmarkUIObserver implementations
+
+    @Override
+    public void onEnhancedBookmarkDelegateInitialized(EnhancedBookmarkDelegate delegate) {
+        mDelegate = delegate;
+        mDelegate.addUIObserver(this);
+
+        EnhancedBookmarkItemsAdapter adapter = new EnhancedBookmarkItemsAdapter(getContext());
+        adapter.onEnhancedBookmarkDelegateInitialized(mDelegate);
+        setAdapter(adapter);
+
+        getLayoutManager().setSpanSizeLookup(new SpanSizeLookup() {
+            @Override
+            public int getSpanSize(int position) {
+                return getAdapter().isHeader(position) ? getLayoutManager().getSpanCount() : 1;
+            }
+        });
+    }
+
+    @Override
+    public void onDestroy() {
+        mDelegate.removeUIObserver(this);
+    }
+
+    @Override
+    public void onAllBookmarksStateSet() {
+        scrollToPosition(0);
+    }
+
+    @Override
+    public void onFolderStateSet(BookmarkId folder) {
+        scrollToPosition(0);
+    }
+
+    @Override
+    public void onFilterStateSet(String filter) {
+        scrollToPosition(0);
+    }
+
+    @Override
+    public void onSelectionStateChange(List<BookmarkId> selectedBookmarks) {
+        if (!mDelegate.isSelectionEnabled()) {
+            for (int i = 0; i < getLayoutManager().getChildCount(); ++i) {
+                View child = getLayoutManager().getChildAt(i);
+                if (child instanceof Checkable) ((Checkable) child).setChecked(false);
+            }
+        }
+    }
+
+    @Override
+    public void onListModeChange(final boolean isListModeEnabled) {
+        if (isListModeEnabled) {
+            removeItemDecoration(mItemDecoration);
+            setPadding(0, 0, 0, 0);
+            getLayoutManager().setSpanCount(1);
+
+            if (isLargeTablet(getContext())) {
+                setClipToPadding(true);
+                setBackgroundResource(R.drawable.eb_item_tile);
+                setMargin(getContext().getResources().getDimensionPixelSize(
+                        R.dimen.enhanced_bookmark_list_mode_background_margin));
+            } else {
+                setBackgroundColor(getContext().getResources().getColor(android.R.color.white));
+            }
+        } else {
+            addItemDecoration(mItemDecoration);
+            setPadding(mItemHalfSpacePx, mItemHalfSpacePx, mItemHalfSpacePx, mItemHalfSpacePx);
+
+            if (isLargeTablet(getContext())) {
+                setClipToPadding(false);
+                setBackgroundResource(0);
+                setMargin(0);
+            } else {
+                setBackgroundColor(
+                        getContext().getResources().getColor(R.color.default_primary_color));
+            }
+            requestLayout();
+        }
+
+        // TODO(ianwen): remember scroll position and scroll back after mode switching.
+        mDelegate.notifyStateChange(this);
+    }
+}