1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.example.android.supportv7.widget;
18
19import android.app.Activity;
20import android.os.Bundle;
21import android.support.v7.widget.DefaultItemAnimator;
22import android.support.v7.widget.LinearLayoutManager;
23import android.support.v7.widget.RecyclerView;
24import android.view.LayoutInflater;
25import android.view.View;
26import android.view.ViewGroup;
27import android.widget.BaseAdapter;
28import android.widget.CheckBox;
29import android.widget.EditText;
30import android.widget.Spinner;
31import android.widget.TextView;
32
33import com.example.android.supportv7.Cheeses;
34import com.example.android.supportv7.R;
35import com.example.android.supportv7.widget.adapter.SimpleStringAdapter;
36import com.example.android.supportv7.widget.util.ConfigToggle;
37import com.example.android.supportv7.widget.util.ConfigViewHolder;
38
39/**
40 * A simple activity that can be extended to demonstrate LayoutManagers.
41 * <p>
42 * It initializes a sample adapter and a list of configuration options. Extending activities can
43 * define the {@link ConfigToggle} list depending on its functionality.
44 */
45abstract public class BaseLayoutManagerActivity<T extends RecyclerView.LayoutManager>
46        extends Activity {
47
48    protected T mLayoutManager;
49
50    protected RecyclerView mRecyclerView;
51
52    private ConfigToggle[] mConfigToggles;
53
54    @Override
55    protected void onCreate(Bundle savedInstanceState) {
56        super.onCreate(savedInstanceState);
57        setContentView(R.layout.activity_base_layout_manager);
58        initToggles();
59        initRecyclerView();
60        initSpinner();
61    }
62
63    abstract protected T createLayoutManager();
64
65    private void initRecyclerView() {
66        mRecyclerView = findViewById(R.id.recycler_view);
67        mRecyclerView.setHasFixedSize(true);
68        mLayoutManager = createLayoutManager();
69        mRecyclerView.setLayoutManager(mLayoutManager);
70        mRecyclerView.setAdapter(createAdapter());
71        ((DefaultItemAnimator)mRecyclerView.getItemAnimator()).setSupportsChangeAnimations(true);
72        onRecyclerViewInit(mRecyclerView);
73    }
74
75    protected void onRecyclerViewInit(RecyclerView recyclerView) {
76
77    }
78
79    protected RecyclerView.Adapter createAdapter() {
80        return new SimpleStringAdapter(this, Cheeses.sCheeseStrings) {
81            @Override
82            public SimpleStringAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
83                    int viewType) {
84                final SimpleStringAdapter.ViewHolder vh = super
85                        .onCreateViewHolder(parent, viewType);
86                vh.itemView.setOnClickListener(new View.OnClickListener() {
87                    @Override
88                    public void onClick(View v) {
89                        final int pos = vh.getAdapterPosition();
90                        if (pos != RecyclerView.NO_POSITION && pos + 1 < getItemCount()) {
91                            swap(pos, pos + 1);
92                        }
93                    }
94                });
95                return vh;
96            }
97        };
98    }
99
100    private void initToggles() {
101        mConfigToggles = createConfigToggles();
102        RecyclerView configView = findViewById(R.id.config_recycler_view);
103        configView.setAdapter(mConfigAdapter);
104        configView.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL,
105                false));
106        configView.setHasFixedSize(true);
107    }
108
109    public void onScrollClicked(View view) {
110        final EditText scrollOffset = findViewById(R.id.scroll_offset);
111        final CheckBox checkBox = findViewById(R.id.enable_smooth_scroll);
112        final Spinner spinner = findViewById(R.id.spinner);
113
114        Integer offset = null;
115        String offsetString = scrollOffset.getText().toString();
116        try {
117            offset = Integer.parseInt(offsetString);
118        } catch (NumberFormatException ex) {
119
120        }
121        final boolean smooth = checkBox.isChecked();
122        if (offset == null) {
123            scrollToPosition(smooth, spinner.getSelectedItemPosition());
124        } else {
125            scrollToPositionWithOffset(smooth, spinner.getSelectedItemPosition(), offset);
126        }
127    }
128
129    private void initSpinner() {
130        final Spinner spinner = findViewById(R.id.spinner);
131        spinner.setAdapter(new BaseAdapter() {
132            @Override
133            public int getCount() {
134                return mRecyclerView.getAdapter().getItemCount();
135            }
136
137            @Override
138            public Integer getItem(int position) {
139                return position;
140            }
141
142            @Override
143            public long getItemId(int position) {
144                return position;
145            }
146
147            @Override
148            public View getView(int position, View convertView, ViewGroup parent) {
149                if (convertView == null) {
150                    convertView = new TextView(parent.getContext());
151                }
152                ((TextView) convertView).setText(" " + position + " ");
153                return convertView;
154            }
155        });
156    }
157
158    protected void scrollToPosition(boolean smooth, int position) {
159        if (smooth) {
160            mRecyclerView.smoothScrollToPosition(position);
161        } else {
162            mRecyclerView.scrollToPosition(position);
163        }
164    }
165
166    protected void scrollToPositionWithOffset(boolean smooth, int position, int offset) {
167        scrollToPosition(smooth, position);
168    }
169
170    protected ConfigToggle[] createConfigToggles() {
171        return new ConfigToggle[] {};
172    }
173
174    private RecyclerView.Adapter mConfigAdapter = new RecyclerView.Adapter<ConfigViewHolder>() {
175        @Override
176        public ConfigViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
177            return new ConfigViewHolder(LayoutInflater.from(parent.getContext())
178                    .inflate(R.layout.config_view_toggle, parent, false));
179        }
180
181        @Override
182        public void onBindViewHolder(ConfigViewHolder holder, int position) {
183            ConfigToggle toggle = mConfigToggles[position];
184            holder.bind(toggle);
185        }
186
187        @Override
188        public int getItemCount() {
189            return mConfigToggles.length;
190        }
191    };
192}
193