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/*
* Copyright (C) 2020 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.android.car.rotaryplayground;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/** Fragment to demo scrolling with CarRecyclerView. */
public class ScrollFragment extends Fragment {
// Item types
private static final int TYPE_BUTTONS = 1;
private static final int TYPE_TEXT = 2;
private View mScrollView;
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container,
@Nullable Bundle savedInstanceState) {
mScrollView = inflater.inflate(R.layout.rotary_scroll, container, false);
initView();
return mScrollView;
}
private void initView() {
List<ScrollListItem> items = new ArrayList<>();
// List of height for items to be added to the demo.
// 0 indicates focusable buttons inflated by R.layout.rotary_scroll.button.
// Values > 0 indiciates non-focusable texts inflated by R.layout.rotary_scroll_text.
final int[] itemHeights = getResources().getIntArray(R.array.scroll_item_heights);
for (int height : itemHeights) {
if (height < 0) {
continue;
}
ScrollListItem item = (height == 0)
? ScrollListItem.createButtonsItem()
: ScrollListItem.createTextItemWithHeight(height);
items.add(item);
}
// Set adapter
Context context = getContext();
ScrollListItemAdapter adapter = new ScrollListItemAdapter(context, items);
RecyclerView view = (RecyclerView) mScrollView.findViewById(R.id.rotary_scroll_view);
view.setAdapter(adapter);
}
/** The adapter used by RotaryScroll to render ScrollListItems. */
private static class ScrollListItemAdapter extends
RecyclerView.Adapter<RecyclerView.ViewHolder> {
final Context mContext;
final List<ScrollListItem> mItems;
ScrollListItemAdapter(Context context, List<ScrollListItem> items) {
this.mContext = context;
this.mItems = items;
}
@NonNull
@Override
public RecyclerView.ViewHolder onCreateViewHolder(
@NonNull ViewGroup viewGroup, int viewType) {
View view;
switch (viewType) {
case TYPE_BUTTONS:
view = LayoutInflater.from(mContext).inflate(
R.layout.rotary_scroll_button, viewGroup, false);
return new RecyclerView.ViewHolder(view) {};
case TYPE_TEXT:
view = LayoutInflater.from(mContext).inflate(
R.layout.rotary_scroll_text, viewGroup, false);
return new ScrollTextHolder(view);
default:
throw new IllegalArgumentException("Unexpected viewType: " + viewType);
}
}
@Override
public int getItemViewType(int position) {
return mItems.get(position).getType();
}
@Override
public void onBindViewHolder(@NonNull RecyclerView.ViewHolder viewHolder, int position) {
if (getItemViewType(position) == TYPE_TEXT) {
((ScrollTextHolder) viewHolder).setHeight(mItems.get(position).getHeight());
}
}
@Override
public int getItemCount() {
return mItems.size();
}
}
/** A ViewHolder for non-focusable ScrollListItems */
private static class ScrollTextHolder extends RecyclerView.ViewHolder {
@NonNull
final TextView mScrollTextView;
ScrollTextHolder(@NonNull View itemView) {
super(itemView);
mScrollTextView = itemView.findViewById(R.id.scroll_text_view);
}
void setHeight(int height) {
mScrollTextView.setHeight(height);
}
}
private static class ScrollListItem {
final int mHeight;
final int mType;
static ScrollListItem createTextItemWithHeight(int height) {
return new ScrollListItem(TYPE_TEXT, height);
}
static ScrollListItem createButtonsItem() {
return new ScrollListItem(TYPE_BUTTONS, 0);
}
ScrollListItem(int type, int height) {
this.mType = type;
this.mHeight = height;
}
int getHeight() {
return mHeight;
}
int getType() {
return mType;
}
}
}
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