1 /*
2  * Copyright (C) 2015 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 
17 package com.example.android.supportv7.widget.touch;
18 
19 import android.app.Activity;
20 import android.graphics.Canvas;
21 import android.os.Bundle;
22 import android.view.LayoutInflater;
23 import android.view.View;
24 import android.view.ViewGroup;
25 import android.widget.Button;
26 import android.widget.TextView;
27 
28 import androidx.annotation.NonNull;
29 import androidx.annotation.Nullable;
30 import androidx.cardview.widget.CardView;
31 import androidx.recyclerview.widget.ItemTouchHelper;
32 import androidx.recyclerview.widget.LinearLayoutManager;
33 import androidx.recyclerview.widget.RecyclerView;
34 
35 import com.example.android.supportv7.Cheeses;
36 import com.example.android.supportv7.R;
37 import com.example.android.supportv7.widget.util.ConfigToggle;
38 import com.example.android.supportv7.widget.util.ConfigViewHolder;
39 
40 import java.util.ArrayList;
41 import java.util.Arrays;
42 import java.util.List;
43 
44 /**
45  * Sample activity from which ItemTouchHelper demo activities inherit.
46  */
47 abstract public class ItemTouchHelperActivity extends Activity {
48 
49     public RecyclerView mRecyclerView;
50 
51     public ItemTouchAdapter mAdapter;
52 
53     public ItemTouchHelper mItemTouchHelper;
54 
55     public ItemTouchHelper.Callback mCallback;
56 
57     private ConfigToggle[] mConfigToggles;
58 
59     @Override
onCreate(Bundle savedInstanceState)60     public void onCreate(Bundle savedInstanceState) {
61         super.onCreate(savedInstanceState);
62         setContentView(R.layout.activity_item_touch);
63         mRecyclerView = findViewById(R.id.recycler_view);
64         mRecyclerView.setHasFixedSize(true);
65         mAdapter = createAdapter();
66         mRecyclerView.setAdapter(mAdapter);
67         mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
68         mItemTouchHelper = createItemTouchHelper();
69         mItemTouchHelper.attachToRecyclerView(mRecyclerView);
70         initToggles();
71     }
72 
initToggles()73     private void initToggles() {
74         mConfigToggles = createConfigToggles();
75         RecyclerView configView = findViewById(R.id.config_recycler_view);
76         configView.setAdapter(new RecyclerView.Adapter<ConfigViewHolder>() {
77             @Override
78             public ConfigViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
79                 return new ConfigViewHolder(LayoutInflater.from(parent.getContext())
80                         .inflate(R.layout.config_view_toggle, parent, false));
81             }
82 
83             @Override
84             public void onBindViewHolder(ConfigViewHolder holder, int position) {
85                 ConfigToggle toggle = mConfigToggles[position];
86                 holder.bind(toggle);
87             }
88 
89             @Override
90             public int getItemCount() {
91                 return mConfigToggles.length;
92             }
93         });
94         configView.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL,
95                 false));
96         configView.setHasFixedSize(true);
97     }
98 
createConfigToggles()99     abstract ConfigToggle[] createConfigToggles();
100 
createItemTouchHelper()101     public ItemTouchHelper createItemTouchHelper() {
102         mCallback = createCallback();
103         return new ItemTouchHelper(mCallback);
104     }
105 
createCallback()106     public ItemTouchHelper.Callback createCallback() {
107         return new ItemTouchHelper.Callback() {
108             @Override
109             public int getMovementFlags(@NonNull RecyclerView recyclerView,
110                     @NonNull RecyclerView.ViewHolder viewHolder) {
111                 return ItemTouchHelperActivity.this.getMovementFlags(recyclerView, viewHolder);
112             }
113 
114             @Override
115             public boolean onMove(@NonNull RecyclerView recyclerView,
116                     @NonNull RecyclerView.ViewHolder viewHolder,
117                     @NonNull RecyclerView.ViewHolder target) {
118                 mAdapter.move(viewHolder.getAdapterPosition(), target.getAdapterPosition());
119                 return true;
120             }
121 
122             @Override
123             public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
124                 mAdapter.delete(viewHolder.getAdapterPosition());
125             }
126 
127             @Override
128             public void onSelectedChanged(@Nullable RecyclerView.ViewHolder viewHolder,
129                     int actionState) {
130                 super.onSelectedChanged(viewHolder, actionState);
131                 ItemTouchHelperActivity.this.onSelectedChanged(viewHolder, actionState);
132             }
133 
134             @Override
135             public void onChildDraw(@NonNull Canvas c, @NonNull RecyclerView recyclerView,
136                     @NonNull RecyclerView.ViewHolder viewHolder,
137                     float dX, float dY, int actionState, boolean isCurrentlyActive) {
138                 if (ItemTouchHelperActivity.this.onChildDraw(c, recyclerView, viewHolder,
139                         dX, dY, actionState, isCurrentlyActive)) {
140                     return;
141                 }
142                 super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState,
143                         isCurrentlyActive);
144             }
145 
146             @Override
147             public void onChildDrawOver(@NonNull Canvas c, @NonNull RecyclerView recyclerView,
148                     RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState,
149                     boolean isCurrentlyActive) {
150                 if (ItemTouchHelperActivity.this.onChildDrawOver(c, recyclerView, viewHolder,
151                         dX, dY, actionState, isCurrentlyActive)) {
152                     return;
153                 }
154                 super.onChildDrawOver(c, recyclerView, viewHolder, dX, dY, actionState,
155                         isCurrentlyActive);
156             }
157 
158             @Override
159             public boolean isLongPressDragEnabled() {
160                 return ItemTouchHelperActivity.this.isLongPressDragEnabled();
161             }
162 
163             @Override
164             public boolean isItemViewSwipeEnabled() {
165                 return ItemTouchHelperActivity.this.isPointerSwipeEnabled();
166             }
167 
168             @Override
169             public void clearView(@NonNull RecyclerView recyclerView,
170                     @NonNull RecyclerView.ViewHolder viewHolder) {
171                 super.clearView(recyclerView, viewHolder);
172                 ItemTouchHelperActivity.this.clearView(viewHolder);
173             }
174         };
175     }
176 
177     /**
178      * @return True if we should NOT call parent
179      */
180     public boolean onChildDraw(Canvas c, RecyclerView recyclerView,
181             RecyclerView.ViewHolder viewHolder,
182             float dX, float dY, int actionState, boolean isCurrentlyActive) {
183         return false;
184     }
185 
186     /**
187      * @return True if we should NOT call parent
188      */
189     public boolean onChildDrawOver(Canvas c, RecyclerView recyclerView,
190             RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState,
191             boolean isCurrentlyActive) {
192         return false;
193     }
194 
195     public void clearView(RecyclerView.ViewHolder viewHolder) {
196 
197     }
198 
199     public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) {
200 
201     }
202 
203     public boolean isLongPressDragEnabled() {
204         return true;
205     }
206 
207     public boolean isPointerSwipeEnabled() {
208         return true;
209     }
210 
211     public ItemTouchViewHolder onCreateViewHolder(ViewGroup parent) {
212         return new ItemTouchViewHolder(
213                 LayoutInflater.from(parent.getContext())
214                         .inflate(R.layout.touch_item, parent, false));
215     }
216 
217     abstract public int getMovementFlags(RecyclerView recyclerView,
218             RecyclerView.ViewHolder viewHolder);
219 
220     public ItemTouchAdapter createAdapter() {
221         return new ItemTouchAdapter();
222     }
223 
224     public void onBind(ItemTouchViewHolder viewHolder) {
225 
226     }
227 
228     public void onCreateViewHolder(ItemTouchViewHolder viewHolder) {
229 
230     }
231 
232     public class ItemTouchViewHolder extends RecyclerView.ViewHolder {
233 
234         public final TextView textView;
235 
236         public final Button actionButton;
237 
238         public final CardView cardView;
239 
240         public final View overlay;
241 
242         public ItemTouchViewHolder(View itemView) {
243             super(itemView);
244             cardView = (CardView) itemView;
245             textView = (TextView) itemView.findViewById(R.id.text_view);
246             actionButton = (Button) itemView.findViewById(R.id.action_button);
247             overlay = itemView.findViewById(R.id.overlay);
248         }
249     }
250 
251     public class ItemTouchAdapter extends RecyclerView.Adapter<ItemTouchViewHolder> {
252 
253         private List<String> mItems = new ArrayList<String>();
254 
255         public ItemTouchAdapter() {
256             mItems.addAll(Arrays.asList(Cheeses.sCheeseStrings));
257         }
258 
259         @Override
260         public ItemTouchViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
261             return ItemTouchHelperActivity.this.onCreateViewHolder(parent);
262         }
263 
264         @Override
265         public void onBindViewHolder(ItemTouchViewHolder holder, int position) {
266             holder.textView.setText(mItems.get(position));
267             onBind(holder);
268         }
269 
270         public void delete(int position) {
271             mItems.remove(position);
272             notifyItemRemoved(position);
273         }
274 
275         public void move(int from, int to) {
276             String prev = mItems.remove(from);
277             mItems.add(to > from ? to - 1 : to, prev);
278             notifyItemMoved(from, to);
279         }
280 
281         @Override
282         public int getItemCount() {
283             return mItems.size();
284         }
285     }
286 
287 
288 }
289