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 package com.example.android.supportv7.widget; 17 18 import android.view.View; 19 import android.view.ViewGroup; 20 21 import androidx.core.view.ViewCompat; 22 import androidx.recyclerview.widget.GridLayoutManager; 23 import androidx.recyclerview.widget.LinearLayoutManager; 24 import androidx.recyclerview.widget.RecyclerView; 25 26 import com.example.android.supportv7.Cheeses; 27 import com.example.android.supportv7.R; 28 import com.example.android.supportv7.widget.adapter.SimpleStringAdapter; 29 import com.example.android.supportv7.widget.util.ConfigToggle; 30 31 /** 32 * A sample Activity to demonstrate capabilities of {@link GridLayoutManager}. 33 */ 34 public class GridLayoutManagerActivity extends BaseLayoutManagerActivity<GridLayoutManager> { 35 SimpleStringAdapter mAdapter; 36 @Override 37 protected GridLayoutManager createLayoutManager() { 38 GridLayoutManager lm = new GridLayoutManager(this, 3); 39 lm.setReverseLayout(true); 40 lm.setSpanSizeLookup(mSpanSizeLookup); 41 return lm; 42 } 43 44 GridLayoutManager.SpanSizeLookup mSpanSizeLookup = new GridLayoutManager.SpanSizeLookup() { 45 @Override 46 public int getSpanSize(int position) { 47 String item = mAdapter.getValueAt(position); 48 return 1 + (Math.abs(item.hashCode()) % mLayoutManager.getSpanCount()); 49 } 50 }; 51 52 @Override 53 protected ConfigToggle[] createConfigToggles() { 54 return new ConfigToggle[]{ 55 new ConfigToggle(this, R.string.checkbox_orientation) { 56 @Override 57 public boolean isChecked() { 58 return mLayoutManager.getOrientation() == LinearLayoutManager.HORIZONTAL; 59 } 60 61 @Override 62 public void onChange(boolean newValue) { 63 mLayoutManager.setOrientation(newValue ? LinearLayoutManager.HORIZONTAL 64 : LinearLayoutManager.VERTICAL); 65 } 66 }, 67 new ConfigToggle(this, R.string.checkbox_reverse) { 68 @Override 69 public boolean isChecked() { 70 return mLayoutManager.getReverseLayout(); 71 } 72 73 @Override 74 public void onChange(boolean newValue) { 75 mLayoutManager.setReverseLayout(newValue); 76 } 77 }, 78 new ConfigToggle(this, R.string.checkbox_layout_dir) { 79 @Override 80 public boolean isChecked() { 81 return ViewCompat.getLayoutDirection(mRecyclerView) == 82 ViewCompat.LAYOUT_DIRECTION_RTL; 83 } 84 85 @Override 86 public void onChange(boolean newValue) { 87 ViewCompat.setLayoutDirection(mRecyclerView, newValue ? 88 ViewCompat.LAYOUT_DIRECTION_RTL : ViewCompat.LAYOUT_DIRECTION_LTR); 89 } 90 }, 91 new ConfigToggle(this, R.string.checkbox_stack_from_end) { 92 @Override 93 public boolean isChecked() { 94 return mLayoutManager.getStackFromEnd(); 95 } 96 97 @Override 98 public void onChange(boolean newValue) { 99 mLayoutManager.setStackFromEnd(newValue); 100 } 101 } 102 }; 103 } 104 105 @Override 106 protected void scrollToPositionWithOffset(boolean smooth, int position, int offset) { 107 if (smooth) { 108 super.scrollToPositionWithOffset(smooth, position, offset); 109 } else { 110 mLayoutManager.scrollToPositionWithOffset(position, offset); 111 } 112 } 113 114 @Override 115 protected RecyclerView.Adapter createAdapter() { 116 mAdapter = new SimpleStringAdapter(this, Cheeses.sCheeseStrings) { 117 @Override 118 public SimpleStringAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, 119 int viewType) { 120 final SimpleStringAdapter.ViewHolder vh = super 121 .onCreateViewHolder(parent, viewType); 122 vh.itemView.setOnClickListener(new View.OnClickListener() { 123 @Override 124 public void onClick(View v) { 125 final int pos = vh.getAdapterPosition(); 126 if (pos == RecyclerView.NO_POSITION) { 127 return; 128 } 129 if (pos + 1 < getItemCount()) { 130 swap(pos, pos + 1); 131 } 132 } 133 }); 134 return vh; 135 } 136 }; 137 return mAdapter; 138 } 139 } 140
