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.google.android.setupdesign.view;
18 
19 import android.annotation.TargetApi;
20 import android.content.Context;
21 import android.content.res.TypedArray;
22 import android.graphics.Color;
23 import android.os.Build.VERSION_CODES;
24 import android.util.AttributeSet;
25 import android.view.ContextThemeWrapper;
26 import android.view.View;
27 import android.widget.Button;
28 import android.widget.LinearLayout;
29 import androidx.annotation.StyleableRes;
30 import com.google.android.setupdesign.R;
31 
32 /**
33  * Custom navigation bar for use with setup wizard. This bar contains a back button, more button and
34  * next button. By default, the more button is hidden, and typically the next button will be hidden
35  * if the more button is shown.
36  *
37  * @see com.google.android.setupdesign.template.RequireScrollMixin
38  */
39 public class NavigationBar extends LinearLayout implements View.OnClickListener {
40 
41   /**
42    * An interface to listen to events of the navigation bar, namely when the user clicks on the back
43    * or next button.
44    */
45   public interface NavigationBarListener {
onNavigateBack()46     void onNavigateBack();
47 
onNavigateNext()48     void onNavigateNext();
49   }
50 
getNavbarTheme(Context context)51   private static int getNavbarTheme(Context context) {
52     // Normally we can automatically guess the theme by comparing the foreground color against
53     // the background color. But we also allow specifying explicitly using sudNavBarTheme.
54     TypedArray attributes =
55         context.obtainStyledAttributes(
56             new int[] {
57               R.attr.sudNavBarTheme, android.R.attr.colorForeground, android.R.attr.colorBackground
58             });
59     @StyleableRes int navBarTheme = 0;
60     @StyleableRes int colorForeground = 1;
61     @StyleableRes int colorBackground = 2;
62     int theme = attributes.getResourceId(navBarTheme, 0);
63     if (theme == 0) {
64       // Compare the value of the foreground against the background color to see if current
65       // theme is light-on-dark or dark-on-light.
66       float[] foregroundHsv = new float[3];
67       float[] backgroundHsv = new float[3];
68       Color.colorToHSV(attributes.getColor(colorForeground, 0), foregroundHsv);
69       Color.colorToHSV(attributes.getColor(colorBackground, 0), backgroundHsv);
70       boolean isDarkBg = foregroundHsv[2] > backgroundHsv[2];
71       theme = isDarkBg ? R.style.SudNavBarThemeDark : R.style.SudNavBarThemeLight;
72     }
73     attributes.recycle();
74     return theme;
75   }
76 
getThemedContext(Context context)77   private static Context getThemedContext(Context context) {
78     final int theme = getNavbarTheme(context);
79     return new ContextThemeWrapper(context, theme);
80   }
81 
82   private Button nextButton;
83   private Button backButton;
84   private Button moreButton;
85   private NavigationBarListener listener;
86 
NavigationBar(Context context)87   public NavigationBar(Context context) {
88     super(getThemedContext(context));
89     init();
90   }
91 
NavigationBar(Context context, AttributeSet attrs)92   public NavigationBar(Context context, AttributeSet attrs) {
93     super(getThemedContext(context), attrs);
94     init();
95   }
96 
97   @TargetApi(VERSION_CODES.HONEYCOMB)
NavigationBar(Context context, AttributeSet attrs, int defStyleAttr)98   public NavigationBar(Context context, AttributeSet attrs, int defStyleAttr) {
99     super(getThemedContext(context), attrs, defStyleAttr);
100     init();
101   }
102 
103   // All the constructors delegate to this init method. The 3-argument constructor is not
104   // available in LinearLayout before v11, so call super with the exact same arguments.
init()105   private void init() {
106     if (isInEditMode()) {
107       return;
108     }
109 
110     View.inflate(getContext(), R.layout.sud_navbar_view, this);
111     nextButton = (Button) findViewById(R.id.sud_navbar_next);
112     backButton = (Button) findViewById(R.id.sud_navbar_back);
113     moreButton = (Button) findViewById(R.id.sud_navbar_more);
114   }
115 
getBackButton()116   public Button getBackButton() {
117     return backButton;
118   }
119 
getNextButton()120   public Button getNextButton() {
121     return nextButton;
122   }
123 
getMoreButton()124   public Button getMoreButton() {
125     return moreButton;
126   }
127 
setNavigationBarListener(NavigationBarListener listener)128   public void setNavigationBarListener(NavigationBarListener listener) {
129     this.listener = listener;
130     if (this.listener != null) {
131       getBackButton().setOnClickListener(this);
132       getNextButton().setOnClickListener(this);
133     }
134   }
135 
136   @Override
onClick(View view)137   public void onClick(View view) {
138     if (listener != null) {
139       if (view == getBackButton()) {
140         listener.onNavigateBack();
141       } else if (view == getNextButton()) {
142         listener.onNavigateNext();
143       }
144     }
145   }
146 }
147