1 /* 2 * Copyright 2019 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.android.car.settings.system; 18 19 import static android.app.Activity.RESULT_OK; 20 21 import android.content.Intent; 22 import android.os.Bundle; 23 import android.view.View; 24 import android.view.ViewTreeObserver; 25 26 import androidx.annotation.Nullable; 27 import androidx.annotation.VisibleForTesting; 28 import androidx.annotation.XmlRes; 29 import androidx.recyclerview.widget.RecyclerView; 30 31 import com.android.car.settings.R; 32 import com.android.car.settings.common.ActivityResultCallback; 33 import com.android.car.settings.common.SettingsFragment; 34 import com.android.car.settings.security.CheckLockActivity; 35 import com.android.car.ui.toolbar.MenuItem; 36 37 import java.util.Collections; 38 import java.util.List; 39 40 /** 41 * Presents the user with the option to reset the head unit to its default "factory" state. If a 42 * user confirms, the user is first required to authenticate and then presented with a secondary 43 * confirmation: {@link MasterClearConfirmFragment}. The user must scroll to the bottom of the page 44 * before proceeding. 45 */ 46 public class MasterClearFragment extends SettingsFragment implements ActivityResultCallback { 47 48 // Arbitrary request code for starting CheckLockActivity when the reset button is clicked. 49 @VisibleForTesting 50 static final int CHECK_LOCK_REQUEST_CODE = 88; 51 52 private MenuItem mMasterClearButton; 53 54 @Override getToolbarMenuItems()55 public List<MenuItem> getToolbarMenuItems() { 56 return Collections.singletonList(mMasterClearButton); 57 } 58 59 @Override onCreate(Bundle savedInstanceState)60 public void onCreate(Bundle savedInstanceState) { 61 super.onCreate(savedInstanceState); 62 63 mMasterClearButton = new MenuItem.Builder(getContext()) 64 .setTitle(R.string.master_clear_button_text) 65 .setEnabled(false) 66 .setOnClickListener(i -> 67 startActivityForResult(new Intent(getContext(), CheckLockActivity.class), 68 CHECK_LOCK_REQUEST_CODE, /* callback= */ MasterClearFragment.this)) 69 .build(); 70 } 71 72 @Override 73 @XmlRes getPreferenceScreenResId()74 protected int getPreferenceScreenResId() { 75 return R.xml.master_clear_fragment; 76 } 77 78 @Override onActivityCreated(Bundle savedInstanceState)79 public void onActivityCreated(Bundle savedInstanceState) { 80 super.onActivityCreated(savedInstanceState); 81 82 RecyclerView recyclerView = getListView(); 83 recyclerView.getViewTreeObserver().addOnGlobalLayoutListener( 84 new ViewTreeObserver.OnGlobalLayoutListener() { 85 @Override 86 public void onGlobalLayout() { 87 mMasterClearButton.setEnabled(isAtEnd()); 88 recyclerView.getViewTreeObserver().removeOnGlobalLayoutListener(this); 89 } 90 }); 91 recyclerView.setOnScrollChangeListener((v, scrollX, scrollY, oldScrollX, oldScrollY) -> { 92 if (isAtEnd()) { 93 mMasterClearButton.setEnabled(true); 94 } 95 }); 96 } 97 98 @Override processActivityResult(int requestCode, int resultCode, @Nullable Intent data)99 public void processActivityResult(int requestCode, int resultCode, @Nullable Intent data) { 100 if (requestCode == CHECK_LOCK_REQUEST_CODE && resultCode == RESULT_OK) { 101 launchFragment(new MasterClearConfirmFragment()); 102 } 103 } 104 105 /** Returns {@code true} if the RecyclerView is completely displaying the last item. */ isAtEnd()106 private boolean isAtEnd() { 107 RecyclerView recyclerView = getListView(); 108 RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager(); 109 if (layoutManager == null || layoutManager.getChildCount() == 0) { 110 return true; 111 } 112 113 int childCount = layoutManager.getChildCount(); 114 View lastVisibleChild = layoutManager.getChildAt(childCount - 1); 115 116 // The list has reached the bottom if the last child that is visible is the last item 117 // in the list and it's fully shown. 118 return layoutManager.getPosition(lastVisibleChild) == (layoutManager.getItemCount() - 1) 119 && layoutManager.getDecoratedBottom(lastVisibleChild) <= layoutManager.getHeight(); 120 } 121 } 122