[Offline pages] Detecting missing offline copy

chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkItemsAdapter.java

Index: chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkItemsAdapter.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkItemsAdapter.java b/chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkItemsAdapter.java
index 8581b8ddd34c598c9e7ebffbd1058fa098160efb..b250fc56f1b0e5035206524815dc9cff6c2a6417 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkItemsAdapter.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkItemsAdapter.java
@@ -18,6 +18,7 @@ import org.chromium.chrome.browser.BookmarksBridge.BookmarkModelObserver;
 import org.chromium.chrome.browser.enhancedbookmarks.EnhancedBookmarkManager.UIState;
 import org.chromium.chrome.browser.enhancedbookmarks.EnhancedBookmarkPromoHeader.PromoHeaderShowingChangeListener;
 import org.chromium.chrome.browser.offlinepages.OfflinePageBridge;
+import org.chromium.chrome.browser.offlinepages.OfflinePageBridge.OfflinePageModelObserver;
 import org.chromium.chrome.browser.offlinepages.OfflinePageFreeUpSpaceCallback;
 import org.chromium.chrome.browser.offlinepages.OfflinePageFreeUpSpaceDialog;
 import org.chromium.chrome.browser.offlinepages.OfflinePageStorageSpaceHeader;
@@ -51,6 +52,7 @@ class EnhancedBookmarkItemsAdapter extends RecyclerView.Adapter<RecyclerView.Vie
     private List<Object> mBookmarkDividerSection = new ArrayList<>();
     private List<BookmarkId> mBookmarkSection = new ArrayList<>();
 
+    private OfflinePageModelObserver mOfflinePageModelObserver;
     private BookmarkModelObserver mBookmarkModelObserver = new BookmarkModelObserver() {
         @Override
         public void bookmarkNodeChanged(BookmarkItem node) {
@@ -272,6 +274,22 @@ class EnhancedBookmarkItemsAdapter extends RecyclerView.Adapter<RecyclerView.Vie
         mPromoHeaderManager = new EnhancedBookmarkPromoHeader(mContext, this);
         OfflinePageBridge offlinePageBridge = mDelegate.getModel().getOfflinePageBridge();
         if (offlinePageBridge != null) {
+            mOfflinePageModelObserver = new OfflinePageModelObserver() {
+                @Override
+                public void offlinePageModelLoaded() {}
+
+                @Override
+                public void offlinePageDeleted(BookmarkId bookmarkId) {
+                    if (mDelegate.getCurrentState() == UIState.STATE_FILTER) {
+                        int deletedPosition = getPositionForBookmark(bookmarkId);
+                        if (deletedPosition >= 0) {
+                            removeItem(deletedPosition);
+                        }
+                    }
+                }
+            };
+            offlinePageBridge.addObserver(mOfflinePageModelObserver);
+
             mOfflineStorageHeader = new OfflinePageStorageSpaceHeader(
                     mContext, offlinePageBridge, new OfflinePageFreeUpSpaceCallback() {
                         @Override
@@ -294,6 +312,10 @@ class EnhancedBookmarkItemsAdapter extends RecyclerView.Adapter<RecyclerView.Vie
     public void onDestroy() {
         mDelegate.removeUIObserver(this);
         mDelegate.getModel().removeObserver(mBookmarkModelObserver);
+        if (mDelegate.getModel().getOfflinePageBridge() != null) {

[jianli, 2015/10/13 00:17:53]

nit: please cache OfflinePageBridge instance.

[fgorski, 2015/10/13 17:39:58]

Done.

+            mDelegate.getModel().getOfflinePageBridge().removeObserver(mOfflinePageModelObserver);
+        }
+
         mPromoHeaderManager.destroy();
         if (mOfflineStorageHeader != null) {

[jianli, 2015/10/13 00:17:53]

Please move this piece to OfflinePageBridge block and you don't need to check
the nullability of mOfflineStorageHeader there.

[fgorski, 2015/10/13 17:39:58]

Done.

             mOfflineStorageHeader.destroy();
@@ -315,6 +337,7 @@ class EnhancedBookmarkItemsAdapter extends RecyclerView.Adapter<RecyclerView.Vie
     public void onFilterStateSet(EnhancedBookmarkFilter filter) {
         assert filter == EnhancedBookmarkFilter.OFFLINE_PAGES;
         setBookmarks(null, mDelegate.getModel().getBookmarkIDsByFilter(filter));
+        mDelegate.getModel().getOfflinePageBridge().checkOfflinePageMetadata();
     }
 
     @Override