Пытаюсь изучить RecycleView, но ни как не могу понять как из MainActivty можно добавить строку в конец RecycleView в уже существующий и отображённый RecycleView? Или это нужно делать в другом месте?
public class MainActivity extends SampleActivityBase {
public static final String TAG = "MainActivity";
private boolean mLogShown;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
RecyclerViewFragment fragment = new RecyclerViewFragment();
transaction.replace(R.id.sample_content_fragment, fragment);
transaction.commit();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
MenuItem logToggle = menu.findItem(R.id.menu_toggle_log);
logToggle.setVisible(findViewById(R.id.sample_output) instanceof ViewAnimator);
logToggle.setTitle(mLogShown ? R.string.sample_hide_log : R.string.sample_show_log);
return super.onPrepareOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch(item.getItemId()) {
case R.id.menu_toggle_log:
mLogShown = !mLogShown;
ViewAnimator output = (ViewAnimator) findViewById(R.id.sample_output);
if (mLogShown) {
output.setDisplayedChild(1);
} else {
output.setDisplayedChild(0);
}
supportInvalidateOptionsMenu();
return true;
}
return super.onOptionsItemSelected(item);
}
/** Create a chain of targets that will receive log data */
@Override
public void initializeLogging() {
// Wraps Android's native log framework.
LogWrapper logWrapper = new LogWrapper();
// Using Log, front-end to the logging chain, emulates android.util.log method signatures.
Log.setLogNode(logWrapper);
// Filter strips out everything except the message text.
MessageOnlyLogFilter msgFilter = new MessageOnlyLogFilter();
logWrapper.setNext(msgFilter);
// On screen logging via a fragment with a TextView.
LogFragment logFragment = (LogFragment) getSupportFragmentManager()
.findFragmentById(R.id.log_fragment);
msgFilter.setNext(logFragment.getLogView());
Log.i(TAG, "Ready");
}
}
Адаптер
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> {
private static final String TAG = "CustomAdapter";
private String[] mDataSet;
// BEGIN_INCLUDE(recyclerViewSampleViewHolder)
/**
* Provide a reference to the type of views that you are using (custom ViewHolder)
*/
public static class ViewHolder extends RecyclerView.ViewHolder {
private final TextView textView;
public ViewHolder(View v) {
super(v);
// Define click listener for the ViewHolder's View.
v.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.d(TAG, "Element " + getAdapterPosition() + " clicked.");
}
});
textView = (TextView) v.findViewById(R.id.textView);
}
public TextView getTextView() {
return textView;
}
}
// END_INCLUDE(recyclerViewSampleViewHolder)
/**
* Initialize the dataset of the Adapter.
*
* @param dataSet String[] containing the data to populate views to be used by RecyclerView.
*/
public CustomAdapter(String[] dataSet) {
mDataSet = dataSet;
}
// BEGIN_INCLUDE(recyclerViewOnCreateViewHolder)
// Create new views (invoked by the layout manager)
@Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
// Create a new view.
View v = LayoutInflater.from(viewGroup.getContext())
.inflate(R.layout.text_row_item, viewGroup, false);
return new ViewHolder(v);
}
@Override
public void onBindViewHolder(ViewHolder viewHolder, final int position) {
Log.d(TAG, "Element " + position + " set.");
// Get element from your dataset at this position and replace the contents of the view
// with that element
viewHolder.getTextView().setText(mDataSet[position]);
}
@Override
public int getItemCount() {
return mDataSet.length;
}
}
Фрагмент
public class RecyclerViewFragment extends Fragment {
private static final String TAG = "RecyclerViewFragment";
private static final String KEY_LAYOUT_MANAGER = "layoutManager";
private static final int SPAN_COUNT = 2;
private static final int DATASET_COUNT = 60;
private enum LayoutManagerType {
GRID_LAYOUT_MANAGER,
LINEAR_LAYOUT_MANAGER
}
protected LayoutManagerType mCurrentLayoutManagerType;
protected RadioButton mLinearLayoutRadioButton;
protected RadioButton mGridLayoutRadioButton;
protected RecyclerView mRecyclerView;
protected CustomAdapter mAdapter;
protected RecyclerView.LayoutManager mLayoutManager;
protected String[] mDataset;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Initialize dataset, this data would usually come from a local content provider or
// remote server.
initDataset();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.recycler_view_frag, container, false);
rootView.setTag(TAG);
// BEGIN_INCLUDE(initializeRecyclerView)
mRecyclerView = (RecyclerView) rootView.findViewById(R.id.recyclerView);
// LinearLayoutManager is used here, this will layout the elements in a similar fashion
// to the way ListView would layout elements. The RecyclerView.LayoutManager defines how
// elements are laid out.
mLayoutManager = new LinearLayoutManager(getActivity());
mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
if (savedInstanceState != null) {
// Restore saved layout manager type.
mCurrentLayoutManagerType = (LayoutManagerType) savedInstanceState
.getSerializable(KEY_LAYOUT_MANAGER);
}
setRecyclerViewLayoutManager(mCurrentLayoutManagerType);
mAdapter = new CustomAdapter(mDataset);
// Set CustomAdapter as the adapter for RecyclerView.
mRecyclerView.setAdapter(mAdapter);
// END_INCLUDE(initializeRecyclerView)
mLinearLayoutRadioButton = (RadioButton) rootView.findViewById(R.id.linear_layout_rb);
mLinearLayoutRadioButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
setRecyclerViewLayoutManager(LayoutManagerType.LINEAR_LAYOUT_MANAGER);
}
});
mGridLayoutRadioButton = (RadioButton) rootView.findViewById(R.id.grid_layout_rb);
mGridLayoutRadioButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
setRecyclerViewLayoutManager(LayoutManagerType.GRID_LAYOUT_MANAGER);
}
});
return rootView;
}
public void setRecyclerViewLayoutManager(LayoutManagerType layoutManagerType) {
int scrollPosition = 0;
// If a layout manager has already been set, get current scroll position.
if (mRecyclerView.getLayoutManager() != null) {
scrollPosition = ((LinearLayoutManager) mRecyclerView.getLayoutManager())
.findFirstCompletelyVisibleItemPosition();
}
switch (layoutManagerType) {
case GRID_LAYOUT_MANAGER:
mLayoutManager = new GridLayoutManager(getActivity(), SPAN_COUNT);
mCurrentLayoutManagerType = LayoutManagerType.GRID_LAYOUT_MANAGER;
break;
case LINEAR_LAYOUT_MANAGER:
mLayoutManager = new LinearLayoutManager(getActivity());
mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
break;
default:
mLayoutManager = new LinearLayoutManager(getActivity());
mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
}
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.scrollToPosition(scrollPosition);
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
// Save currently selected layout manager.
savedInstanceState.putSerializable(KEY_LAYOUT_MANAGER, mCurrentLayoutManagerType);
super.onSaveInstanceState(savedInstanceState);
}
/**
* Generates Strings for RecyclerView's adapter. This data would usually come
* from a local content provider or remote server.
*/
private void initDataset() {
mDataset = new String[DATASET_COUNT];
for (int i = 0; i < DATASET_COUNT; i++) {
mDataset[i] = "This is element #" + i;
}
}
}
