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      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 androidx.annotation.StyleableRes;
     25 import android.util.AttributeSet;
     26 import android.view.ContextThemeWrapper;
     27 import android.view.View;
     28 import android.widget.Button;
     29 import android.widget.LinearLayout;
     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 {
     46     void onNavigateBack();
     47 
     48     void onNavigateNext();
     49   }
     50 
     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 
     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 
     87   public NavigationBar(Context context) {
     88     super(getThemedContext(context));
     89     init();
     90   }
     91 
     92   public NavigationBar(Context context, AttributeSet attrs) {
     93     super(getThemedContext(context), attrs);
     94     init();
     95   }
     96 
     97   @TargetApi(VERSION_CODES.HONEYCOMB)
     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.
    105   private void init() {
    106     View.inflate(getContext(), R.layout.sud_navbar_view, this);
    107     nextButton = (Button) findViewById(R.id.sud_navbar_next);
    108     backButton = (Button) findViewById(R.id.sud_navbar_back);
    109     moreButton = (Button) findViewById(R.id.sud_navbar_more);
    110   }
    111 
    112   public Button getBackButton() {
    113     return backButton;
    114   }
    115 
    116   public Button getNextButton() {
    117     return nextButton;
    118   }
    119 
    120   public Button getMoreButton() {
    121     return moreButton;
    122   }
    123 
    124   public void setNavigationBarListener(NavigationBarListener listener) {
    125     this.listener = listener;
    126     if (this.listener != null) {
    127       getBackButton().setOnClickListener(this);
    128       getNextButton().setOnClickListener(this);
    129     }
    130   }
    131 
    132   @Override
    133   public void onClick(View view) {
    134     if (listener != null) {
    135       if (view == getBackButton()) {
    136         listener.onNavigateBack();
    137       } else if (view == getNextButton()) {
    138         listener.onNavigateNext();
    139       }
    140     }
    141   }
    142 }
    143