blob: 8ec3a2338b2a375be67d4d73285f58803b7415c2 [file] [log] [blame]
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.supportv7.widget;
import com.example.android.supportv7.Cheeses;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.view.MenuItemCompat;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.util.AsyncListUtil;
import android.view.Menu;
import android.view.MenuItem;
import android.view.ViewGroup;
import android.widget.TextView;
/**
* A sample Activity to demonstrate capabilities of {@link AsyncListUtil}.
*/
public class AsyncListUtilActivity extends Activity {
private static final String TAG = "AsyncListUtilActivity";
private RecyclerView mRecyclerView;
private LinearLayoutManager mLinearLayoutManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mRecyclerView = new RecyclerView(this);
mLinearLayoutManager = new LinearLayoutManager(this);
mRecyclerView.setLayoutManager(mLinearLayoutManager);
mRecyclerView.setHasFixedSize(true);
final ViewGroup.LayoutParams layoutParams = new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
mRecyclerView.setLayoutParams(layoutParams);
mRecyclerView.setAdapter(new AsyncAdapter());
setContentView(mRecyclerView);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
MenuItemCompat.setShowAsAction(menu.add("Layout"), MenuItemCompat.SHOW_AS_ACTION_IF_ROOM);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
mRecyclerView.requestLayout();
return super.onOptionsItemSelected(item);
}
private static class TextViewHolder extends RecyclerView.ViewHolder {
TextView textView;
public TextViewHolder(Context context) {
super(new TextView(context));
textView = (TextView) itemView;
}
}
private class AsyncAdapter extends RecyclerView.Adapter<TextViewHolder> {
private AsyncListUtil<String> mAsyncListUtil;
AsyncAdapter() {
mAsyncListUtil = new AsyncStringListUtil();
}
@Override
public TextViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new TextViewHolder(parent.getContext());
}
@Override
public void onBindViewHolder(TextViewHolder holder, int position) {
final String itemString = mAsyncListUtil.getItem(position);
if (itemString == null) {
holder.textView.setText("loading...");
} else {
holder.textView.setText(itemString);
}
}
@Override
public int getItemCount() {
return mAsyncListUtil.getItemCount();
}
}
private class AsyncStringListUtil extends AsyncListUtil<String> {
private static final int TILE_SIZE = 5;
private static final long DELAY_MS = 500;
public AsyncStringListUtil() {
super(String.class, TILE_SIZE,
new AsyncListUtil.DataCallback<String>() {
@Override
public int refreshData() {
return Cheeses.sCheeseStrings.length;
}
@Override
public void fillData(String[] data, int startPosition, int itemCount) {
sleep();
for (int i = 0; i < itemCount; i++) {
data[i] = Cheeses.sCheeseStrings[startPosition + i];
}
}
private void sleep() {
try {
Thread.sleep(DELAY_MS);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
},
new AsyncListUtil.ViewCallback() {
@Override
public void getItemRangeInto(int[] outRange) {
outRange[0] = mLinearLayoutManager.findFirstVisibleItemPosition();
outRange[1] = mLinearLayoutManager.findLastVisibleItemPosition();
}
@Override
public void onDataRefresh() {
mRecyclerView.getAdapter().notifyDataSetChanged();
}
@Override
public void onItemLoaded(int position) {
mRecyclerView.getAdapter().notifyItemChanged(position);
}
});
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
onRangeChanged();
}
});
}
}
}