androidx.recyclerview.widget.RecyclerView#getContext ( )源码实例Demo

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setSupportActionBar(R.id.otl_toolbar);
    final RecyclerView list = findViewById(R.id.otl_content);
    final Drawable divider = ContextCompat.getDrawable(this, R.drawable.divider_common);
    if (divider != null) {
        final DividerItemDecoration decoration = new DividerItemDecoration(list.getContext(),
                DividerItemDecoration.VERTICAL);
        decoration.setDrawable(divider);
        list.addItemDecoration(decoration);
    }

    list.setAdapter(mAdapter);
    mPresenter.loadOpenType();
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_simple_recycler_view);

    RecyclerView simpleRecyclerView = findViewById(R.id.simple_recycler_view);

    // add data in the mPersonList
    addPersonData();


    // set layout manager
    LinearLayoutManager layoutManager = new LinearLayoutManager(this);
    simpleRecyclerView.setLayoutManager(layoutManager);

    // set divider between two rows
    DividerItemDecoration divider = new DividerItemDecoration(simpleRecyclerView.getContext(), layoutManager.getOrientation());
    simpleRecyclerView.addItemDecoration(divider);

    // set adapter
    RecyclerViewJavaAdapter adapter = new RecyclerViewJavaAdapter(personModelList,this);
    simpleRecyclerView.setAdapter(adapter);

}
 

@Nullable
@Override
public View onCreateView(
    LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
  View rootView = inflater.inflate(R.layout.gallery_note_fragment, null);

  RecyclerView gallery = rootView.findViewById(R.id.gallery);
  GridLayoutManager layoutManager =
      new GridLayoutManager(
          gallery.getContext(),
          gallery.getContext().getResources().getInteger(R.integer.gallery_column_count));
  gallery.setLayoutManager(layoutManager);
  gallery.setItemAnimator(new DefaultItemAnimator());
  gallery.setAdapter(galleryAdapter);
  addButton = rootView.findViewById(R.id.btn_add);

  requestPermission();
  attachAddButton(addButton);
  actionController.attachAddButton(addButton);
  actionController.attachProgressBar(rootView.findViewById(R.id.recording_progress_bar));
  setUpTitleBar(rootView, false, R.string.action_bar_gallery, R.drawable.ic_gallery);

  return rootView;
}
 

public SmsTemplateListAsyncAdapter(int chunkSize,
    DatabaseAdapter db,
    SmsTemplateListSource itemSource,
    RecyclerView recyclerView,
    SmsDragListActivity activity) {
    super(chunkSize, itemSource, recyclerView);
    this.context = recyclerView.getContext();
    this.db = db;
    this.activity = activity;
}
 

private void setupAlignment(RecyclerView recycler) {
    if (!mAlreadyAligned) {
        //setting alignment of header
        ViewGroup.LayoutParams currentParams = getLayoutParams();
        FrameLayout.LayoutParams newHeaderParams;
        int width = ViewGroup.LayoutParams.WRAP_CONTENT;
        int height = ViewGroup.LayoutParams.WRAP_CONTENT;
        int gravity = (mReversed ? Gravity.BOTTOM : Gravity.TOP) | Gravity.CENTER_HORIZONTAL;
        if (currentParams != null) {
            newHeaderParams = new FrameLayout.LayoutParams(getLayoutParams()); //to copy all the margins
            newHeaderParams.width = width;
            newHeaderParams.height = height;
            newHeaderParams.gravity = gravity;
        } else {
            newHeaderParams = new FrameLayout.LayoutParams(width, height, gravity);
        }
        RecyclerViewHeader.this.setLayoutParams(newHeaderParams);

        //setting alignment of recycler
        FrameLayout newRootParent = new FrameLayout(recycler.getContext());
        newRootParent.setLayoutParams(recycler.getLayoutParams());
        ViewParent currentParent = recycler.getParent();
        if (currentParent instanceof ViewGroup) {
            int indexWithinParent = ((ViewGroup) currentParent).indexOfChild(recycler);

            ((ViewGroup) currentParent).removeViewAt(indexWithinParent);
            recycler.setLayoutParams(new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            newRootParent.addView(recycler);
            newRootParent.addView(RecyclerViewHeader.this);
            ((ViewGroup) currentParent).addView(newRootParent, indexWithinParent);
        }
    }
}
 

private void setupRecyclerView(List<String> files) {
    RecyclerView recyclerView = findViewById(R.id.rv_document_list);
    LinearLayoutManager horizontalLayoutManager
            = new LinearLayoutManager(this,
            LinearLayoutManager.HORIZONTAL, false);
    recyclerView.setLayoutManager(horizontalLayoutManager);
    DividerItemDecoration dividerItemDecoration =
            new DividerItemDecoration(recyclerView.getContext(),
                    horizontalLayoutManager.getOrientation());
    recyclerView.addItemDecoration(dividerItemDecoration);
    adapter = new SimpleListRvAdapter(this, files);
    adapter.setClickListener(this);
    recyclerView.setAdapter(adapter);
}
 

/**
 * Creates a new SelectionTracker.Builder useful for configuring and creating
 * a new SelectionTracker for use with your {@link RecyclerView}.
 *
 * @param selectionId   A unique string identifying this selection in the context
 *                      of the activity or fragment.
 * @param recyclerView  the owning RecyclerView
 * @param keyProvider   the source of selection keys
 * @param detailsLookup the source of information about RecyclerView items.
 * @param storage       Strategy for type-safe storage of selection state in
 *                      {@link Bundle}.
 */
public Builder(
        @NonNull String selectionId,
        @NonNull RecyclerView recyclerView,
        @NonNull ItemKeyProvider<K> keyProvider,
        @NonNull ItemDetailsLookup<K> detailsLookup,
        @NonNull StorageStrategy<K> storage) {

    checkArgument(selectionId != null);
    checkArgument(!selectionId.trim().isEmpty());
    checkArgument(recyclerView != null);

    mSelectionId = selectionId;
    mRecyclerView = recyclerView;
    mContext = recyclerView.getContext();
    mAdapter = recyclerView.getAdapter();

    checkArgument(mAdapter != null);
    checkArgument(keyProvider != null);
    checkArgument(detailsLookup != null);
    checkArgument(storage != null);

    mDetailsLookup = detailsLookup;
    mKeyProvider = keyProvider;
    mStorage = storage;

    mBandPredicate = new BandPredicate.NonDraggableArea(mRecyclerView, detailsLookup);
}
 

@Override public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state,
    int position) {
  RecyclerView.SmoothScroller smoothScroller =
      new TopSnappedSmoothScroller(recyclerView.getContext());
  smoothScroller.setTargetPosition(position);
  startSmoothScroll(smoothScroller);
}
 

public ItemTouchListenerAdapter(
        RecyclerView recyclerView,
        RecyclerViewOnItemClickListener listener) {
    if (recyclerView == null || listener == null) {
        throw new IllegalArgumentException("RecyclerView and Listener arguments can not be null");
    }
    this.recyclerView = recyclerView;
    this.listener = listener;
    this.gestureDetector = new GestureDetector(recyclerView.getContext(), this);
}
 

private void setupRecyclerView(List<String> files) {
    RecyclerView recyclerView = findViewById(R.id.rv_document_list);
    LinearLayoutManager horizontalLayoutManager
            = new LinearLayoutManager(this,
            LinearLayoutManager.HORIZONTAL, false);
    recyclerView.setLayoutManager(horizontalLayoutManager);
    DividerItemDecoration dividerItemDecoration =
            new DividerItemDecoration(recyclerView.getContext(),
                    horizontalLayoutManager.getOrientation());
    recyclerView.addItemDecoration(dividerItemDecoration);
    adapter = new SimpleListRvAdapter(this, files);
    adapter.setClickListener(this);
    recyclerView.setAdapter(adapter);
}
 

@Override
protected void onCreate(@Nullable final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_scanner);
    ButterKnife.bind(this);

    // Create view model containing utility methods for scanning
    mViewModel = new ViewModelProvider(this, mViewModelFactory).get(ScannerViewModel.class);

    final Toolbar toolbar = findViewById(R.id.toolbar);
    toolbar.setTitle(R.string.title_scanner);
    setSupportActionBar(toolbar);
    //noinspection ConstantConditions
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    if (getIntent() != null) {
        mScanWithProxyService = getIntent().getBooleanExtra(Utils.EXTRA_DATA_PROVISIONING_SERVICE, true);
        if (mScanWithProxyService) {
            getSupportActionBar().setSubtitle(R.string.sub_title_scanning_nodes);
        } else {
            getSupportActionBar().setSubtitle(R.string.sub_title_scanning_proxy_node);
        }
    }

    // Configure the recycler view
    final RecyclerView recyclerViewDevices = findViewById(R.id.recycler_view_ble_devices);
    recyclerViewDevices.setLayoutManager(new LinearLayoutManager(this));
    final DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerViewDevices.getContext(), DividerItemDecoration.VERTICAL);
    recyclerViewDevices.addItemDecoration(dividerItemDecoration);

    final SimpleItemAnimator itemAnimator = (SimpleItemAnimator) recyclerViewDevices.getItemAnimator();
    if (itemAnimator != null) itemAnimator.setSupportsChangeAnimations(false);

    final DevicesAdapter adapter = new DevicesAdapter(this, mViewModel.getScannerRepository().getScannerResults());
    adapter.setOnItemClickListener(this);
    recyclerViewDevices.setAdapter(adapter);

    mViewModel.getScannerRepository().getScannerState().observe(this, this::startScan);
}
 

@Override
public void smoothScrollToPosition(
    RecyclerView recyclerView, RecyclerView.State state, int position) {
  final LinearSmoothScroller linearSmoothScroller =
      new LinearSmoothScroller(recyclerView.getContext()) {

        @Override
        protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) {
          return MILLISECONDS_PER_INCH / displayMetrics.densityDpi;
        }
      };
  linearSmoothScroller.setTargetPosition(position);
  startSmoothScroll(linearSmoothScroller);
}
 

@Override
public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state, int position) {
    RecyclerView.SmoothScroller smoothScroller = new TopSnappedSmoothScroller(recyclerView.getContext());
    smoothScroller.setTargetPosition(position);
    startSmoothScroll(smoothScroller);
}
 

public StickyRecyclerHeadersTouchListener(@NonNull final RecyclerView recyclerView,
                                          final StickyRecyclerHeadersDecoration decor) {
    mTapDetector = new GestureDetector(recyclerView.getContext(), new SingleTapDetector());
    mRecyclerView = recyclerView;
    mDecor = decor;
}
 

public StickyRecyclerHeadersTouchListener(final RecyclerView recyclerView,
    final com.marshalchen.ultimaterecyclerview.stickyheadersrecyclerview.StickyRecyclerHeadersDecoration decor) {
  mTapDetector = new GestureDetector(recyclerView.getContext(), new SingleTapDetector());
  mRecyclerView = recyclerView;
  mDecor = decor;
}
 

public void enableDragDrop(RecyclerView recyclerView) {
    ItemTouchHelper.Callback callback = new MyItemTouchHelperCallback(recyclerView.getContext());
    mItemTouchHelper = new ItemTouchHelper(callback);
    mItemTouchHelper.attachToRecyclerView(recyclerView);
}
 

@SuppressWarnings("ConstantConditions")
@Override
protected void onCreate(@Nullable final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_ranges);
    ButterKnife.bind(this);
    mViewModel = new ViewModelProvider(this, mViewModelFactory).get(RangesViewModel.class);
    mType = getIntent().getExtras().getInt(Utils.RANGE_TYPE);

    //Bind ui
    final Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    final RecyclerView recyclerView = findViewById(R.id.recycler_view);
    final View rangesContainer = findViewById(R.id.info_ranges);
    rangesContainer.findViewById(R.id.container).setVisibility(View.VISIBLE);
    mRangeView = rangesContainer.findViewById(R.id.range);
    final TextView startAddress = rangesContainer.findViewById(R.id.start_address);
    final TextView endAddress = rangesContainer.findViewById(R.id.end_address);
    final ExtendedFloatingActionButton fab_add = findViewById(R.id.fab_add);

    mProvisioner = mViewModel.getSelectedProvisioner().getValue();

    switch (mType) {
        case Utils.GROUP_RANGE:
            startAddress.setText(MeshAddress.formatAddress(MeshAddress.START_GROUP_ADDRESS, true));
            endAddress.setText(MeshAddress.formatAddress(MeshAddress.END_GROUP_ADDRESS, true));
            getSupportActionBar().setTitle(R.string.title_edit_group_ranges);
            mRangeAdapter = new RangeAdapter(this,
                    mProvisioner.getProvisionerUuid(),
                    mProvisioner.getAllocatedGroupRanges(),
                    mViewModel.getNetworkLiveData().getProvisioners());
            break;
        case Utils.SCENE_RANGE:
            startAddress.setText(MeshAddress.formatAddress(0x0000, true));
            endAddress.setText(MeshAddress.formatAddress(0xFFFF, true));
            getSupportActionBar().setTitle(R.string.title_edit_scene_ranges);
            mRangeAdapter = new RangeAdapter(this,
                    mProvisioner.getProvisionerUuid(),
                    mProvisioner.getAllocatedSceneRanges(),
                    mViewModel.getNetworkLiveData().getProvisioners());
            break;
        default:
        case Utils.UNICAST_RANGE:
            startAddress.setText(MeshAddress.formatAddress(MeshAddress.START_UNICAST_ADDRESS, true));
            endAddress.setText(MeshAddress.formatAddress(MeshAddress.END_UNICAST_ADDRESS, true));
            getSupportActionBar().setTitle(R.string.title_edit_unicast_ranges);
            mRangeAdapter = new RangeAdapter(this,
                    mProvisioner.getProvisionerUuid(),
                    mProvisioner.getAllocatedUnicastRanges(),
                    mViewModel.getNetworkLiveData().getProvisioners());
            break;
    }

    mRangeAdapter.setOnItemClickListener(this);

    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    final DividerItemDecoration dividerItemDecoration =
            new DividerItemDecoration(recyclerView.getContext(), DividerItemDecoration.VERTICAL);
    recyclerView.addItemDecoration(dividerItemDecoration);
    recyclerView.setItemAnimator(new DefaultItemAnimator());
    recyclerView.setAdapter(mRangeAdapter);
    final ItemTouchHelper.Callback itemTouchHelperCallback = new RemovableItemTouchHelperCallback(this);
    final ItemTouchHelper itemTouchHelper = new ItemTouchHelper(itemTouchHelperCallback);
    itemTouchHelper.attachToRecyclerView(recyclerView);

    fab_add.setOnClickListener(v -> {
        switch (mType) {
            case Utils.GROUP_RANGE:
                final DialogFragmentGroupRange groupRange = DialogFragmentGroupRange.newInstance(null);
                groupRange.show(getSupportFragmentManager(), null);
                break;
            case Utils.SCENE_RANGE:
                final DialogFragmentSceneRange sceneRange = DialogFragmentSceneRange.newInstance(null);
                sceneRange.show(getSupportFragmentManager(), null);
                break;
            default:
            case Utils.UNICAST_RANGE:
                final DialogFragmentUnicastRange unicastRange = DialogFragmentUnicastRange.newInstance(null);
                unicastRange.show(getSupportFragmentManager(), null);
                break;
        }
    });

    mFabResolve.setOnClickListener(v -> resolveRanges());

    updateRanges();
    updateOtherRanges();
    updateEmptyView();
    updateResolveFab();
}
 

@Nullable
@Override
public View onCreateView(@NonNull final LayoutInflater inflater, @Nullable final ViewGroup container, @Nullable final Bundle savedInstanceState) {
    @SuppressLint("InflateParams") final View rootView = inflater.inflate(R.layout.fragment_groups, null);
    mViewModel = new ViewModelProvider(requireActivity(), mViewModelFactory).get(SharedViewModel.class);
    ButterKnife.bind(this, rootView);

    final ExtendedFloatingActionButton fab = rootView.findViewById(R.id.fab_add_group);

    // Configure the recycler view
    final RecyclerView recyclerViewGroups = rootView.findViewById(R.id.recycler_view_groups);
    recyclerViewGroups.setLayoutManager(new LinearLayoutManager(requireContext()));
    final DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerViewGroups.getContext(), DividerItemDecoration.VERTICAL);
    recyclerViewGroups.addItemDecoration(dividerItemDecoration);
    final ItemTouchHelper.Callback itemTouchHelperCallback = new RemovableItemTouchHelperCallback(this);
    final ItemTouchHelper itemTouchHelper = new ItemTouchHelper(itemTouchHelperCallback);
    itemTouchHelper.attachToRecyclerView(recyclerViewGroups);
    final GroupAdapter adapter = new GroupAdapter(requireContext());
    adapter.setOnItemClickListener(this);
    recyclerViewGroups.setAdapter(adapter);

    mViewModel.getNetworkLiveData().observe(getViewLifecycleOwner(), meshNetworkLiveData -> {
        if (meshNetworkLiveData != null) {
            if (meshNetworkLiveData.getMeshNetwork().getGroups().isEmpty()) {
                mEmptyView.setVisibility(View.VISIBLE);
            } else {
                mEmptyView.setVisibility(View.INVISIBLE);
            }
        }
    });

    mViewModel.getGroups().observe(getViewLifecycleOwner(), groups -> {
        final MeshNetwork network = mViewModel.getNetworkLiveData().getMeshNetwork();
        adapter.updateAdapter(network, groups);
    });

    fab.setOnClickListener(v -> {
        DialogFragmentCreateGroup fragmentCreateGroup = DialogFragmentCreateGroup.newInstance();
        fragmentCreateGroup.show(getChildFragmentManager(), null);
    });

    recyclerViewGroups.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrolled(@NonNull final RecyclerView recyclerView, final int dx, final int dy) {
            super.onScrolled(recyclerView, dx, dy);
            final LinearLayoutManager m = (LinearLayoutManager) recyclerView.getLayoutManager();
            if (m != null) {
                if (m.findFirstCompletelyVisibleItemPosition() == 0) {
                    fab.extend();
                } else {
                    fab.shrink();
                }
            }
        }
    });

    return rootView;

}
 

@Override
protected void onCreate(@Nullable final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_keys);
    mViewModel = new ViewModelProvider(this, mViewModelFactory).get(AppKeysViewModel.class);

    //Bind ui
    ButterKnife.bind(this);

    final Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    //noinspection ConstantConditions
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    final ExtendedFloatingActionButton fab = findViewById(R.id.fab_add);
    final RecyclerView appKeysRecyclerView = findViewById(R.id.recycler_view_keys);
    appKeysRecyclerView.setLayoutManager(new LinearLayoutManager(this));
    final DividerItemDecoration dividerItemDecoration =
            new DividerItemDecoration(appKeysRecyclerView.getContext(), DividerItemDecoration.VERTICAL);
    appKeysRecyclerView.addItemDecoration(dividerItemDecoration);
    appKeysRecyclerView.setItemAnimator(new DefaultItemAnimator());

    final Bundle bundle = getIntent().getExtras();
    if (bundle != null) {
        switch (bundle.getInt(EXTRA_DATA)) {
            case MANAGE_APP_KEY:
                break;
            case ADD_APP_KEY:
                getSupportActionBar().setTitle(R.string.title_select_app_key);
                fab.hide();
                mAdapter = new ManageAppKeyAdapter(this, mViewModel.getNetworkLiveData());
                mAdapter.setOnItemClickListener(this);
                appKeysRecyclerView.setAdapter(mAdapter);
                setUpObserver();
                break;
            case BIND_APP_KEY:
            case PUBLICATION_APP_KEY:
                getSupportActionBar().setTitle(R.string.title_select_app_key);
                fab.hide();
                //Get selected mesh node
                final ProvisionedMeshNode node = mViewModel.getSelectedMeshNode().getValue();
                if (node != null) {
                    final List<NodeKey> applicationKeys = node.getAddedAppKeys();
                    if (!applicationKeys.isEmpty()) {
                        mAdapter = new ManageAppKeyAdapter(mViewModel.getNetworkLiveData().getAppKeys(), applicationKeys);
                        mAdapter.setOnItemClickListener(this);
                        appKeysRecyclerView.setAdapter(mAdapter);
                    } else {
                        final TextView textView = mEmptyView.findViewById(R.id.rationale);
                        textView.setText(R.string.no_added_app_keys_rationale);
                        mEmptyView.setVisibility(View.VISIBLE);
                    }
                }
                break;
        }
    } else {
        getSupportActionBar().setTitle(R.string.title_manage_app_keys);
        final ItemTouchHelper.Callback itemTouchHelperCallback = new RemovableItemTouchHelperCallback(this);
        final ItemTouchHelper itemTouchHelper = new ItemTouchHelper(itemTouchHelperCallback);
        itemTouchHelper.attachToRecyclerView(appKeysRecyclerView);
        mAdapter = new ManageAppKeyAdapter(this, mViewModel.getNetworkLiveData());
        mAdapter.setOnItemClickListener(this);
        appKeysRecyclerView.setAdapter(mAdapter);
        setUpObserver();
    }


    fab.setOnClickListener(v -> {
        final Intent intent = new Intent(this, AddAppKeyActivity.class);
        startActivity(intent);
    });

    appKeysRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrolled(@NonNull final RecyclerView recyclerView, final int dx, final int dy) {
            super.onScrolled(recyclerView, dx, dy);
            final LinearLayoutManager m = (LinearLayoutManager) recyclerView.getLayoutManager();
            if (m != null) {
                if (m.findFirstCompletelyVisibleItemPosition() == 0) {
                    fab.extend();
                } else {
                    fab.shrink();
                }
            }
        }
    });
}
 

@Override
public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state, int position) {
    RecyclerView.SmoothScroller smoothScroller = new CenterSmoothScroller(recyclerView.getContext());
    smoothScroller.setTargetPosition(position);
    startSmoothScroll(smoothScroller);
}