android.support.v7.widget.RecyclerView.OnScrollListener Java Examples

/**
 * Initializes the RecyclerView.
 *
 * @param adapter The adapter that provides a binding from an app-specific data set to views
 *                that are displayed within the RecyclerView.
 * @return The RecyclerView itself.
 */
public RecyclerView initializeRecyclerView(Adapter<RecyclerView.ViewHolder> adapter) {
    mAdapter = adapter;
    mAdapter.registerAdapterDataObserver(mAdapterObserver);

    mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
    mRecyclerView.setAdapter(mAdapter);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));

    mRecyclerView.setHasFixedSize(true);
    mRecyclerView.addOnScrollListener(new OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            setToolbarShadowVisibility();
        }
    });

    mItemAnimator = mRecyclerView.getItemAnimator();

    return mRecyclerView;
}
 

@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
	super.onScrollStateChanged(recyclerView, newState);
	switch (newState) {
	case android.widget.AbsListView.OnScrollListener.SCROLL_STATE_IDLE:
		adapter.onResume();
		break;
	case android.widget.AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL:
		// adapter.pause();
		adapter.onResume();
		break;
	case android.widget.AbsListView.OnScrollListener.SCROLL_STATE_FLING:
		adapter.onPause();
		break;
	}
	if (listener2 != null)
		listener2.onScrollStateChanged(recyclerView, newState);

}
 

/**
 * 获取ListView对象
 */
protected void getRefreshView() {
    int childs = getChildCount();
    if (childs > 0) {
        View childView = getChildAt(0);
        if (childView instanceof RecyclerView) {
            mRecyclerView = (RecyclerView) childView;
            // 设置滚动监听器给ListView, 使得滚动的情况下也可以自动加载
            mRecyclerView.setOnScrollListener(mScrollListener);
            mRecyclerView.setOnScrollListener(new OnScrollListener() {
            });
        }
    }
}
 

private void initializeResources() {
  this.recipients     = RecipientFactory.getRecipientsForIds(getActivity(), getActivity().getIntent().getLongArrayExtra("recipients"), true);
  this.threadId       = this.getActivity().getIntent().getLongExtra("thread_id", -1);
  this.lastSeen       = this.getActivity().getIntent().getLongExtra(ConversationActivity.LAST_SEEN_EXTRA, -1);
  this.firstLoad      = true;

  OnScrollListener scrollListener = new ConversationScrollListener(getActivity());
  list.addOnScrollListener(scrollListener);
}
 

/**
 * 添加相关用户显示</br>
 * 
 * @param users
 */
@Override
public void showRelativeUserView(List<CommUser> users) {
    mAdapter.getDataSource().clear();
    if (users == null || users.size() == 0) {
        mMoreView.setVisibility(View.GONE);
        // invalidate
        mAdapter.notifyDataSetChanged();
        return;
    }
    int itemWidth = mAdapter.computeWidth();
    LayoutParams params = mRecyclerView.getLayoutParams();
    if (users.size() > 4) {
        mMoreView.setVisibility(View.VISIBLE);
        params.width = (SearchUsersAdapter.MAX_SHOW_NUM - 1) * itemWidth;
    } else {
        params.width = users.size() * itemWidth;
        mMoreView.setVisibility(View.GONE);
    }
    mRecyclerView.setLayoutParams(params);
    mRecyclerView.invalidate();
    mAdapter.getDataSource().addAll(users);
    mAdapter.notifyDataSetChanged();
    AlphaAnimation alphaAnimation = new AlphaAnimation(0, 1);
    alphaAnimation.setDuration(400);
    alphaAnimation.setFillAfter(true);
    LayoutAnimationController layoutAnimationController = new LayoutAnimationController(
            alphaAnimation, 0.4f);
    mRecyclerView.setLayoutAnimation(layoutAnimationController);

    mRecyclerView.setOnScrollListener(new OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            int visibleItemCount = mLinearLayoutManager.getChildCount();
            int totalItemCount = mLinearLayoutManager.getItemCount();
            int pastVisiblesItems = mLinearLayoutManager.findFirstVisibleItemPosition();

            if ((visibleItemCount + pastVisiblesItems) >= totalItemCount) {
                ((SearchPresenter) mPresenter).loadMoreUser();
            }
        }
    });
}
 

public SuggestionsBottomSheetContent(final ChromeActivity activity, final BottomSheet sheet,
        TabModelSelector tabModelSelector, SnackbarManager snackbarManager) {
    Profile profile = Profile.getLastUsedProfile();
    SuggestionsNavigationDelegate navigationDelegate =
            new SuggestionsNavigationDelegateImpl(activity, profile, sheet, tabModelSelector);
    mTileGroupDelegate = new TileGroupDelegateImpl(
            activity, profile, tabModelSelector, navigationDelegate, snackbarManager);
    mSuggestionsUiDelegate = createSuggestionsDelegate(
            profile, navigationDelegate, sheet, activity.getReferencePool());

    mView = LayoutInflater.from(activity).inflate(
            R.layout.suggestions_bottom_sheet_content, null);
    mRecyclerView = (SuggestionsRecyclerView) mView.findViewById(R.id.recycler_view);

    TouchEnabledDelegate touchEnabledDelegate = new TouchEnabledDelegate() {
        @Override
        public void setTouchEnabled(boolean enabled) {
            activity.getBottomSheet().setTouchEnabled(enabled);
        }
    };
    mContextMenuManager =
            new ContextMenuManager(activity, navigationDelegate, touchEnabledDelegate);
    activity.getWindowAndroid().addContextMenuCloseListener(mContextMenuManager);
    mSuggestionsUiDelegate.addDestructionObserver(new DestructionObserver() {
        @Override
        public void onDestroy() {
            activity.getWindowAndroid().removeContextMenuCloseListener(mContextMenuManager);
        }
    });

    UiConfig uiConfig = new UiConfig(mRecyclerView);

    final NewTabPageAdapter adapter = new NewTabPageAdapter(mSuggestionsUiDelegate,
            /* aboveTheFoldView = */ null, uiConfig, OfflinePageBridge.getForProfile(profile),
            mContextMenuManager, mTileGroupDelegate);
    mRecyclerView.init(uiConfig, mContextMenuManager, adapter);

    mBottomSheetObserver = new SuggestionsSheetVisibilityChangeObserver(this, activity) {
        @Override
        public void onSheetOpened() {
            mRecyclerView.scrollToPosition(0);
            adapter.refreshSuggestions();
            mSuggestionsUiDelegate.getEventReporter().onSurfaceOpened();
            mRecyclerView.getScrollEventReporter().reset();

            if (ChromeFeatureList.isEnabled(
                        ChromeFeatureList.CONTEXTUAL_SUGGESTIONS_CAROUSEL)
                    && sheet.getActiveTab() != null) {
                updateContextualSuggestions(sheet.getActiveTab().getUrl());
            }

            super.onSheetOpened();
        }

        @Override
        public void onContentShown() {
            SuggestionsMetrics.recordSurfaceVisible();
        }

        @Override
        public void onContentHidden() {
            SuggestionsMetrics.recordSurfaceHidden();
        }

        @Override
        public void onContentStateChanged(@BottomSheet.SheetState int contentState) {
            if (contentState == BottomSheet.SHEET_STATE_HALF) {
                SuggestionsMetrics.recordSurfaceHalfVisible();
            } else if (contentState == BottomSheet.SHEET_STATE_FULL) {
                SuggestionsMetrics.recordSurfaceFullyVisible();
            }
        }
    };

    mShadowView = (FadingShadowView) mView.findViewById(R.id.shadow);
    mShadowView.init(
            ApiCompatibilityUtils.getColor(mView.getResources(), R.color.toolbar_shadow_color),
            FadingShadow.POSITION_TOP);

    mRecyclerView.addOnScrollListener(new OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            boolean shadowVisible = mRecyclerView.canScrollVertically(-1);
            mShadowView.setVisibility(shadowVisible ? View.VISIBLE : View.GONE);
        }
    });

    final LocationBar locationBar = (LocationBar) sheet.findViewById(R.id.location_bar);
    mRecyclerView.setOnTouchListener(new View.OnTouchListener() {
        @Override
        @SuppressLint("ClickableViewAccessibility")
        public boolean onTouch(View view, MotionEvent motionEvent) {
            if (locationBar != null && locationBar.isUrlBarFocused()) {
                locationBar.setUrlBarFocus(false);
            }

            // Never intercept the touch event.
            return false;
        }
    });
}
 

/**
 * Creates a new HistoryManager.
 * @param activity The Activity associated with the HistoryManager.
 * @param isSeparateActivity Whether the history UI will be shown in a separate activity than
 *                           the main Chrome activity.
 * @param snackbarManager The {@link SnackbarManager} used to display snackbars.
 */
@SuppressWarnings("unchecked") // mSelectableListLayout
public HistoryManager(
        Activity activity, boolean isSeparateActivity, SnackbarManager snackbarManager) {
    mActivity = activity;
    mIsSeparateActivity = isSeparateActivity;
    mSnackbarManager = snackbarManager;

    mSelectionDelegate = new SelectionDelegate<>();
    mSelectionDelegate.addObserver(this);
    mHistoryAdapter = new HistoryAdapter(mSelectionDelegate, this,
            sProviderForTests != null ? sProviderForTests : new BrowsingHistoryBridge());

    // 1. Create SelectableListLayout.
    mSelectableListLayout =
            (SelectableListLayout<HistoryItem>) LayoutInflater.from(activity).inflate(
                    R.layout.history_main, null);

    // 2. Initialize RecyclerView.
    mRecyclerView = mSelectableListLayout.initializeRecyclerView(mHistoryAdapter);

    // 3. Initialize toolbar.
    mToolbar = (HistoryManagerToolbar) mSelectableListLayout.initializeToolbar(
            R.layout.history_toolbar, mSelectionDelegate, R.string.menu_history, null,
            R.id.normal_menu_group, R.id.selection_mode_menu_group,
            R.color.default_primary_color, this);
    mToolbar.setManager(this);
    mToolbar.initializeSearchView(this, R.string.history_manager_search, R.id.search_menu_id);

    // 4. Width constrain the SelectableListLayout.
    mSelectableListLayout.configureWideDisplayStyle();

    // 5. Initialize empty view.
    mEmptyView = mSelectableListLayout.initializeEmptyView(
            VectorDrawableCompat.create(
                    mActivity.getResources(), R.drawable.history_big, mActivity.getTheme()),
            R.string.history_manager_empty, R.string.history_manager_no_results);

    // 6. Create large icon bridge.
    mLargeIconBridge = new LargeIconBridge(Profile.getLastUsedProfile().getOriginalProfile());
    ActivityManager activityManager = ((ActivityManager) ContextUtils
            .getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE));
    int maxSize = Math.min((activityManager.getMemoryClass() / 4) * MEGABYTES_TO_BYTES,
            FAVICON_MAX_CACHE_SIZE_BYTES);
    mLargeIconBridge.createCache(maxSize);

    // 7. Initialize the adapter to load items.
    mHistoryAdapter.initialize();

    // 8. Add scroll listener to page in more items when necessary.
    mRecyclerView.addOnScrollListener(new OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            if (!mHistoryAdapter.canLoadMoreItems()) return;

            // Load more items if the scroll position is close to the bottom of the list.
            LinearLayoutManager layoutManager =
                    (LinearLayoutManager) recyclerView.getLayoutManager();
            if (layoutManager.findLastVisibleItemPosition()
                    > (mHistoryAdapter.getItemCount() - 25)) {
                mHistoryAdapter.loadMoreItems();
                recordUserActionWithOptionalSearch("LoadMoreOnScroll");
            }
        }});

    // 9. Listen to changes in sign in state.
    SigninManager.get(mActivity).addSignInStateObserver(this);

    recordUserAction("Show");
}
 

public IPauseOnScrollRecycler getOnScrollListener(OnScrollListener l) {
	return new IPauseOnScrollRecycler(this, l);
}
 

public IPauseOnScrollRecycler(IXPauseListener adapter,
		OnScrollListener listener) {
	this.adapter = adapter;
	this.listener2 = listener;
}
 

public void setOnScrollListener(OnScrollListener l) {
    // hijack the scroll listener setter and have this list also notify the additional listener
    mAdditionalOnScrollListener = l;
}
 

/**
 * 使外部可以监听到listview的滚动
 * 
 * @param listener
 */
public void addOnScrollListener(OnScrollListener listener) {
    mListViewOnScrollListener = listener;
}