Android Studio中的手机通讯录开发

Android Studio中的手机通讯录，包含功能（按首字母排序，动态添加）

第一次写博客，也刚踏入工作，想着把自己在项目中遇到的问题，以及自己在工作中所做的项目记录下来，方便以后自己查找知识，一开始没有接触过Android，为了找工作，自学了5个月的Java，到公司实习的主要负责任务是安卓开发。
第一个做的任务就是做的手机通讯录，虽然做出来了，但是还是大多数借鉴网络上的，自己再做了一点修改。
下面是自己做的效果图，供大家参考，写的不好，大家就随便看看，希望对借鉴的人有点参考的意义。

上面几幅图形是运行成功候的图像，接下来就是代码部分。

MainActivity 主页面功能代码

package com.example.lastmodel;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
     
    private ImageButton addUser;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
     
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        addUser = findViewById(R.id.addUser);
        addUser.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
     

        startActivity(new Intent(MainActivity.this,AddUserActivity.class));

    }
}

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/tv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="联系人"
        android:layout_centerHorizontal="true"
        android:textSize="30dp"/>
    <ImageButton
        android:id="@+id/addUser"
        android:layout_width="60dp"
        android:layout_height="60dp"
        android:layout_alignParentBottom="true"
        android:layout_alignParentEnd="true"
        android:layout_alignParentRight="true"
        android:background="@drawable/add"/>
RelativeLayout>

AddUserActivity 添加联系人页面功能

package com.example.lastmodel;

import android.content.ContentValues;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

/**
 * @author: hanxuan
 * @date: 2020/12/2
 */

public class AddUserActivity extends AppCompatActivity implements View.OnClickListener {
     
    private MyDatabaseHelper dbHelper;
    private EditText username,telnumber;
    private Button ok_add;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
     
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_add_user);

        dbHelper = new MyDatabaseHelper(this,"Use.db",null,1);
        username = findViewById(R.id.add_user_name);
        telnumber = findViewById(R.id.add_user_telnumber);

        ok_add = findViewById(R.id.ok_add);
        ok_add.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
     
        switch (v.getId()){
     
            case R.id.ok_add:{
     
                String name = username.getText().toString();
                String tel_number = telnumber.getText().toString();
                if (name == null||tel_number == null){
     
                    Toast.makeText(this,"用户名和电话不能为空",Toast.LENGTH_SHORT).show();
                }else {
     
                    SQLiteDatabase db = dbHelper.getReadableDatabase();
                    ContentValues values = new ContentValues();
                    values.put("name",name);
                    values.put("telnumber",tel_number);
                    db.insert("Use",null,values);
                    Toast.makeText(this,"添加成功",Toast.LENGTH_SHORT).show();
                    startActivity(new Intent(AddUserActivity.this,UserListViewActivity.class));
                    this.finish();
                    db.close();
                }
            }

        }
    }
}

activity_add_user.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".AddUserActivity">

    <EditText
        android:id="@+id/add_user_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:hint="姓名"/>
    <EditText
        android:id="@+id/add_user_telnumber"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_below="@+id/add_user_name"
        android:hint="电话号码"/>

    <Button
        android:id="@+id/ok_add"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/add_user_telnumber"
        android:text="添加"/>

RelativeLayout>

UserListViewActivity 展示姓名的页面功能

package com.example.lastmodel;

import android.animation.Animator;
import android.animation.ObjectAnimator;
import android.annotation.SuppressLint;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.Window;
import android.widget.ListView;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;


import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
 * @author: hanxuan
 * @date: 2020/12/2
 */
public class UserListViewActivity extends AppCompatActivity {
     
    private MyDatabaseHelper dbHelper;
    private RecyclerView mRecyclerView;
    private List<SortModel> SourceDateList;
    private SideBar sideBar;
    private TextView dialog;
    private SortAdapter adapter;
    private ClearEditText mClearEditText;
    private PinyinComparator pinyinComparator;
    LinearLayoutManager manager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
     
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_user_list_view);

        dbHelper = new MyDatabaseHelper(this,"User4.db",null,1);
        initViews();
        initUser();

        mRecyclerView = findViewById(R.id.recyclerView);
        
        SourceDateList = filledData(SourceDateList);

    }

    private void initViews()  {
     
        pinyinComparator = new PinyinComparator();

        sideBar =  findViewById(R.id.sideBar);
        dialog =  findViewById(R.id.dialog);
        sideBar.setTextView(dialog);

        sideBar.setOnTouchingLetterChangedListener(new SideBar.OnTouchingLetterChangedListener() {
     

            @Override
            public void onTouchingLetterChanged(String s) {
     
                //该字母首次出现的位置
                int position = adapter.getPositionForSection(s.charAt(0));
                if (position != -1) {
     
                    manager.scrollToPositionWithOffset(position, 0);
                }

            }
        });
        mClearEditText =  findViewById(R.id.filter_edit);
        mClearEditText.addTextChangedListener(new TextWatcher() {
     

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
     
                filterData(s.toString());
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
     
            }
            @Override
            public void afterTextChanged(Editable s) {
     
            }
        });


    }

    public  List<SortModel> initUser(){
     
        SourceDateList = new ArrayList<>();
        SQLiteDatabase db = dbHelper.getReadableDatabase();
        Cursor cursor = db.query("Use",null,null,null,null,null,null);
        if (cursor.moveToFirst()){
     
            do{
     
                String name = cursor.getString(cursor.getColumnIndex("name"));

                SortModel data = new SortModel(name);
                //SourceDateList.add(data);
                SourceDateList.add(data);
            }while (cursor.moveToNext());
        }
        cursor.close();
        return SourceDateList;
    }

    private List<SortModel> filledData(List<SortModel> list) {
     
        List<SortModel> mSortList = new ArrayList<>();

        for (int i = 0; i < list.size(); i++) {
     
            SortModel sortModel = list.get(i);
            //sortModel.setName(list.get(i));
            //汉字转换成拼音
            String pinyin = PinyinUtils.getPingYin(list.get(i).getName());
            String sortString = pinyin.substring(0, 1).toUpperCase();

            // 正则表达式，判断首字母是否是英文字母
            if (sortString.matches("[A-Z]")) {
     
                sortModel.setLetters(sortString.toUpperCase());
            } else {
     
                sortModel.setLetters("#");
            }

            mSortList.add(sortModel);
        }
        return mSortList;

    }

    private void filterData(String filterStr) {
     
        List<SortModel> filterDateList = new ArrayList<>();

        if (TextUtils.isEmpty(filterStr)) {
     
            filterDateList = SourceDateList;
        } else {
     
            filterDateList.clear();
            for (SortModel sortModel : SourceDateList) {
     
                String name = sortModel.getName();
                if (name.indexOf(filterStr.toString()) != -1 ||
                        PinyinUtils.getFirstSpell(name).startsWith(filterStr.toString())
                        //不区分大小写
                        || PinyinUtils.getFirstSpell(name).toLowerCase().startsWith(filterStr.toString())
                        || PinyinUtils.getFirstSpell(name).toUpperCase().startsWith(filterStr.toString())
                ) {
     
                    filterDateList.add(sortModel);
                }
            }
        }
        // 根据a-z进行排序
        Collections.sort(filterDateList, pinyinComparator);
        adapter.updateList(filterDateList);
    }
}

activity_user_list_view.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:focusable="true"
    android:focusableInTouchMode="true">

    <com.example.lastmodel.ClearEditText
        android:id="@+id/filter_edit"
        android:layout_width="match_parent"
        android:layout_height="38dp"
        android:layout_marginLeft="12dp"
        android:layout_marginTop="10dp"
        android:layout_marginRight="12dp"
        android:layout_marginBottom="5dp"
        android:background="@drawable/shape"
        android:drawableLeft="@drawable/drawable"
        android:hint="搜索联系人"
        android:maxLines="1"
        android:paddingLeft="8dp"
        android:textSize="17dp" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recyclerView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            />

        <TextView
            android:id="@+id/dialog"
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:layout_centerInParent="true"
            android:background="#A9A9A9"
            android:gravity="center"
            android:textColor="	#000000"
            android:textSize="30dp"
            android:visibility="invisible" />

        <com.example.lastmodel.SideBar
            android:id="@+id/sideBar"
            android:layout_width="30dp"
            android:layout_height="match_parent"
            android:layout_alignParentRight="true"
            />
    RelativeLayout>

LinearLayout>

以上的代码就是界面以及部分功能实现的代码，接下来的代码就是辅助类。

CharPortraitView.java

该类主要的功能是获得名字的首汉字，以及名字前面的圆形和随机分布圆形的颜色

package com.example.lastmodel;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.graphics.drawable.GradientDrawable;

import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;

import androidx.appcompat.widget.AppCompatTextView;
import androidx.core.widget.TextViewCompat;

import java.util.Random;
/**
 * @author: hanxuan
 * @date: 2020/12/2
 */

public class CharPortraitView extends AppCompatTextView {
     

    private boolean isRandom = false;
    private Random random;
    private int mBackColor;
    private Context mContext;
    private String[] colors;
    private boolean mHead=true;
    private String mContent;


    public CharPortraitView(Context context) {
     
        this(context, null);
    }

    public CharPortraitView(Context context, AttributeSet attrs) {
     
        super(context, attrs);
        mContext = context;
        init(attrs);
        build();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
     
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int width = View.MeasureSpec.getSize(widthMeasureSpec);
        int height = View.MeasureSpec.getSize(heightMeasureSpec);
        int minSize = Math.min(width, height);
        setMeasuredDimension(minSize, minSize);
    }

    private void init(AttributeSet attrs) {
     
        // 初始化随机数
        random = new Random();
        // 获取参数
        TypedArray array = mContext.obtainStyledAttributes(attrs, R.styleable.CharPortraitView);
        // 获取是否随机背景
        isRandom = array.getBoolean(R.styleable.CharPortraitView_random, false);
        // 获取背景颜色
        mBackColor = array.getColor(R.styleable.CharPortraitView_back_color, Color.BLUE);
        array.recycle();
    }
    //设置
    private void build() {
     
        if (!isRandom) {
     
            mBackColor = getRandomColor(); //产生随机颜色
        }
        // 设置居中
        setGravity(Gravity.CENTER);
        // 设置自适应文字大小
        TextViewCompat.setAutoSizeTextTypeWithDefaults(this, TextViewCompat.AUTO_SIZE_TEXT_TYPE_UNIFORM);
        // 设置背景颜色
        setBackgroundResource(R.drawable.shape_drawable);
        GradientDrawable drawable = (GradientDrawable) getBackground();
        drawable.setColor(mBackColor);
        setBackgroundDrawable(drawable);
        if (mContent==null){
     
            return;
        }
        if (mHead){
     
            setText(mContent.substring(0, 1));//取首字符显示
        }else {
     
            setText(mContent.substring(mContent.length()-1, mContent.length()));//取末尾字符显示
        }
    }
    /**
     * 设置文本内容
     *@param mHead  true 第一个字符 false 最后一个字符
     *@return
     */
    public CharPortraitView setHead(boolean mHead) {
     
        this.mHead=mHead;
        build();
        return this;
    }
    //设置文本内容
    public CharPortraitView setContent(String str) {
     
        this.mContent=str;
        build();
        return this;
    }

    //设置背景颜色
    public CharPortraitView setBackColor(int backColor) {
     
        mBackColor = backColor;
        isRandom = false;
        build();
        return this;
    }
    //设置是否开启随机颜色
    public CharPortraitView setRandom(boolean isRandom) {
     
        this.isRandom = isRandom;
        build();
        return this;
    }
    /**
     * 设置随机背景颜色数组
     * @param colors
     * @return
     */
    public CharPortraitView setBackColor(String[] colors){
     
        this.colors=colors;
        build();
        return this;
    }
    /**
     * 获取随机背景颜色
     * @return
     */
    private int getRandomColor() {
     
        String[] colorArray;
        if (colors!=null&&colors.length>0){
     
           colorArray=colors;
        }else {
     
            colorArray=mContext.getResources().getStringArray(R.array.color);
        }
        int value = random.nextInt(colorArray.length);
        return Color.parseColor(colorArray[value]);
    }

}

ClearEditText.java

该类主要是实现清除搜索栏的内容

package com.example.lastmodel;

import android.content.Context;
import android.graphics.drawable.Drawable;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnFocusChangeListener;
import android.view.animation.Animation;
import android.view.animation.CycleInterpolator;
import android.view.animation.TranslateAnimation;
import android.widget.EditText;
/**
 * @author: hanxuan
 * @date: 2020/12/2
 */

public class ClearEditText extends androidx.appcompat.widget.AppCompatEditText implements OnFocusChangeListener, TextWatcher {
     
    private Drawable mClearDrawable;
 
    public ClearEditText(Context context) {
      
    	this(context, null); 
    } 
 
    public ClearEditText(Context context, AttributeSet attrs) {
      
    	this(context, attrs, android.R.attr.editTextStyle);
    } 
    
    public ClearEditText(Context context, AttributeSet attrs, int defStyle) {
     
        super(context, attrs, defStyle);
        init();
    }
    
    
    private void init() {
      
    	mClearDrawable = getCompoundDrawables()[2];
        if (mClearDrawable == null) {
      
        	mClearDrawable = getResources().getDrawable(R.drawable.guanbifanhuishanchu);
        } 
        mClearDrawable.setBounds(-17, 5, mClearDrawable.getIntrinsicWidth(), mClearDrawable.getIntrinsicHeight());
        setClearIconVisible(false); 
        setOnFocusChangeListener(this); 
        addTextChangedListener(this); 
    } 

    @Override 
    public boolean onTouchEvent(MotionEvent event) {
      
        if (getCompoundDrawables()[2] != null) {
      
            if (event.getAction() == MotionEvent.ACTION_UP) {
      
            	boolean touchable = event.getX() > (getWidth() 
                        - getPaddingRight() - mClearDrawable.getIntrinsicWidth()) 
                        && (event.getX() < ((getWidth() - getPaddingRight())));
                if (touchable) {
      
                    this.setText(""); 
                } 
            } 
        } 
 
        return super.onTouchEvent(event); 
    } 
 
    @Override
    public void onFocusChange(View v, boolean hasFocus) {
      
        if (hasFocus) {
      
            setClearIconVisible(getText().length() > 0); 
        } else {
      
            setClearIconVisible(false); 
        } 
    } 
 
 
    protected void setClearIconVisible(boolean visible) {
     
        Drawable right = visible ? mClearDrawable : null; 
        setCompoundDrawables(getCompoundDrawables()[0], 
                getCompoundDrawables()[1], right, getCompoundDrawables()[3]); 
    } 
     
    
    @Override
    public void onTextChanged(CharSequence s, int start, int count, 
            int after) {
      
        setClearIconVisible(s.length() > 0); 
    } 
 
    @Override 
    public void beforeTextChanged(CharSequence s, int start, int count, 
            int after) {
      
         
    } 
 
    @Override 
    public void afterTextChanged(Editable s) {
      
         
    } 
    
   
    public void setShakeAnimation(){
     
    	this.setAnimation(shakeAnimation(5));
    }
    
    
    public static Animation shakeAnimation(int counts){
     
    	Animation translateAnimation = new TranslateAnimation(0, 10, 0, 0);
    	translateAnimation.setInterpolator(new CycleInterpolator(counts));
    	translateAnimation.setDuration(1000);
    	return translateAnimation;
    }
 
 
}

MyDatabaseHelper.java

数据库的创建

package com.example.lastmodel;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;

import androidx.annotation.Nullable;
/**
 * @author: hanxuan
 * @date: 2020/12/2
 */
public class MyDatabaseHelper extends SQLiteOpenHelper {
     
    public static final String Create_Table_User = "create table Use (" + "name text," + "telnumber text)";
    private Context mContext;

    public MyDatabaseHelper(@Nullable Context context, @Nullable String name, @Nullable SQLiteDatabase.CursorFactory factory, int version) {
     
        super(context, name, factory, version);

    }


    @Override
    public void onCreate(SQLiteDatabase db) {
     
        db.execSQL(Create_Table_User);
        //Toast.makeText(mContext,"创建成功", Toast.LENGTH_SHORT).show();

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
     

    }
}

PinyinComparator.java

package com.example.lastmodel;

import java.util.Comparator;

public class PinyinComparator implements Comparator<SortModel> {
     

	public int compare(SortModel o1, SortModel o2) {
     
		if (o1.getLetters().equals("@")
				|| o2.getLetters().equals("#")) {
     
			return -1;
		} else if (o1.getLetters().equals("#")
				|| o2.getLetters().equals("@")) {
     
			return 1;
		} else {
     
			return o1.getLetters().compareTo(o2.getLetters());
		}
	}

}

PinyinUtils.java

package com.example.lastmodel;


import net.sourceforge.pinyin4j.PinyinHelper;
import net.sourceforge.pinyin4j.format.HanyuPinyinCaseType;
import net.sourceforge.pinyin4j.format.HanyuPinyinOutputFormat;
import net.sourceforge.pinyin4j.format.HanyuPinyinToneType;
import net.sourceforge.pinyin4j.format.HanyuPinyinVCharType;
import net.sourceforge.pinyin4j.format.exception.BadHanyuPinyinOutputFormatCombination;
/**
 * @author: hanxuan
 * @date: 2020/12/2
 */
public class PinyinUtils {
     
    /**
     * 获取拼音
     *
     * @param inputString
     * @return
     */
    public static String getPingYin(String inputString) {
     
        HanyuPinyinOutputFormat format = new HanyuPinyinOutputFormat();
        format.setCaseType(HanyuPinyinCaseType.LOWERCASE);
        format.setToneType(HanyuPinyinToneType.WITHOUT_TONE);
        format.setVCharType(HanyuPinyinVCharType.WITH_V);

        char[] input = inputString.trim().toCharArray();
        String output = "";

        try {
     
            for (char curChar : input) {
     
                if (Character.toString(curChar).matches("[\\u4E00-\\u9FA5]+")) {
     
                    /*至少匹配一个汉字的写法，这两个unicode值正好时Unicode表中的汉字的头和尾
                    * []代表里面的值出现一个就可以， 后边的"+"代表至少出现1次，合起来即至少匹配一个汉字*/
                    String[] temp = PinyinHelper.toHanyuPinyinStringArray(curChar, format);
                    output += temp[0];
                } else
                    output += Character.toString(curChar);
            }
        } catch (BadHanyuPinyinOutputFormatCombination e) {
     
            e.printStackTrace();
        }
        return output;
    }

    /**
     * 获取第一个字的拼音首字母
     * @param chinese
     * @return
     */
    public static String getFirstSpell(String chinese) {
     
        StringBuffer pinYinBF = new StringBuffer();
        char[] arr = chinese.toCharArray();
        HanyuPinyinOutputFormat defaultFormat = new HanyuPinyinOutputFormat();
        defaultFormat.setCaseType(HanyuPinyinCaseType.LOWERCASE);
        defaultFormat.setToneType(HanyuPinyinToneType.WITHOUT_TONE);
        for (char curChar : arr) {
     
            if (curChar > 128) {
     
                try {
     
                    String[] temp = PinyinHelper.toHanyuPinyinStringArray(curChar, defaultFormat);
                    if (temp != null) {
     
                        pinYinBF.append(temp[0].charAt(0));
                    }
                } catch (BadHanyuPinyinOutputFormatCombination e) {
     
                    e.printStackTrace();
                }
            } else {
     
                pinYinBF.append(curChar);
            }
        }
        return pinYinBF.toString().replaceAll("\\W", "").trim();
    }

}

SideBar.java

右边侧滑栏的实现

package com.example.lastmodel;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.graphics.drawable.ColorDrawable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.TextView;
/**
 * @author: hanxuan
 * @date: 2020/12/2
 */
public class SideBar extends View {
     
	// 触摸事件
	private OnTouchingLetterChangedListener onTouchingLetterChangedListener;
	public static String[] b = {
      "A", "B", "C", "D", "E", "F", "G", "H", "I",
			"J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V",
			"W", "X", "Y", "Z","#"};
	private int choose = -1;
	private Paint paint = new Paint();

	private TextView mTextDialog;

	/**
	 * 为SideBar设置显示字母的TextView
	 * @param textDialog
	 */
	public void setTextView(TextView textDialog) {
     
		this.mTextDialog = textDialog;
	}


	public SideBar(Context context, AttributeSet attrs, int defStyle) {
     
		super(context, attrs, defStyle);
	}

	public SideBar(Context context, AttributeSet attrs) {
     
		super(context, attrs);
	}

	public SideBar(Context context) {
     
		super(context);
	}

	protected void onDraw(Canvas canvas) {
     
		super.onDraw(canvas);
		int height = getHeight();
		int width = getWidth();
		int singleHeight = height / b.length;

		for (int i = 0; i < b.length; i++) {
     
			paint.setColor(Color.rgb(105, 105, 105));
			// paint.setColor(Color.WHITE);
			paint.setTypeface(Typeface.DEFAULT_BOLD);
			paint.setAntiAlias(true);
			paint.setTextSize(35);
			if (i == choose) {
     
				paint.setColor(Color.parseColor("#3399ff"));
				paint.setFakeBoldText(true);
			}

			float xPos = width / 2 - paint.measureText(b[i]) / 2;
			float yPos = singleHeight * i + singleHeight;
			canvas.drawText(b[i], xPos, yPos, paint);
			paint.reset();
		}

	}

	@Override
	public boolean dispatchTouchEvent(MotionEvent event) {
     
		final int action = event.getAction();
		final float y = event.getY();
		final int oldChoose = choose;
		final OnTouchingLetterChangedListener listener = onTouchingLetterChangedListener;
		final int c = (int) (y / getHeight() * b.length);


		switch (action) {
     
		case MotionEvent.ACTION_UP:
			setBackground(new ColorDrawable(0x00000000));
			choose = -1;
			invalidate();
			if (mTextDialog != null) {
     
				mTextDialog.setVisibility(View.INVISIBLE);
			}
			break;

		default:
			setBackgroundResource(R.drawable.sidebar_background);
			if (oldChoose != c) {
     
				if (c >= 0 && c < b.length) {
     
					if (listener != null) {
     
						listener.onTouchingLetterChanged(b[c]);
					}
					if (mTextDialog != null) {
     
						mTextDialog.setText(b[c]);
						mTextDialog.setVisibility(View.VISIBLE);
					}
					
					choose = c;
					invalidate();
				}
			}

			break;
		}
		return true;
	}


	public void setOnTouchingLetterChangedListener(
			OnTouchingLetterChangedListener onTouchingLetterChangedListener) {
     
		this.onTouchingLetterChangedListener = onTouchingLetterChangedListener;
	}


	public interface OnTouchingLetterChangedListener {
     
		void onTouchingLetterChanged(String s);
	}

}

SortAdapter.java

首字母排序功能

package com.example.lastmodel;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;

import androidx.recyclerview.widget.RecyclerView;

import java.util.List;

/**
 * @author: hanxuan
 * @date: 2020/12/2
 */

public class SortAdapter extends RecyclerView.Adapter<SortAdapter.ViewHolder> {
     
    private LayoutInflater mInflater;
    private List<SortModel> mData;
    private Context mContext;


    public SortAdapter(Context context, List<SortModel> data) {
     
        mInflater = LayoutInflater.from(context);
        mData = data;
        this.mContext = context;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
     
        View view = mInflater.inflate(R.layout.item, parent,false);
        ViewHolder viewHolder = new ViewHolder(view);
        viewHolder.tvTag = view.findViewById(R.id.tag);
        viewHolder.tvName = view.findViewById(R.id.name);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) {
     
        int section = getSectionForPosition(position);
        //如果当前位置等于该分类首字母的Char的位置 ，则认为是第一次出现
        if (position == getPositionForSection(section)) {
     
            holder.tvTag.setVisibility(View.VISIBLE);
            holder.tvTag.setText(mData.get(position).getLetters());
            holder.portrait.setContent(mData.get(position).getName()).setHead(true);
        } else {
     
            holder.tvTag.setVisibility(View.GONE);
            holder.portrait.setContent(mData.get(position).getName()).setHead(true);
        }
        if (mOnItemClickListener != null) {
     
            holder.itemView.setOnClickListener(new View.OnClickListener() {
     
                @Override
                public void onClick(View v) {
     
                    mOnItemClickListener.onItemClick(holder.itemView, position);
                }
            });
        }
        holder.tvName.setText(this.mData.get(position).getName());
        holder.tvName.setOnClickListener(new View.OnClickListener() {
     
            @Override
            public void onClick(View view) {
     
                Toast.makeText(mContext, mData.get(position).getName(),Toast.LENGTH_SHORT).show();
            }
        });
    }
    @Override
    public int getItemCount() {
     
        return mData.size();
    }

    public interface OnItemClickListener {
     
        void onItemClick(View view, int position);
    }

    private OnItemClickListener mOnItemClickListener;

    public void setOnItemClickListener(OnItemClickListener mOnItemClickListener) {
     
        this.mOnItemClickListener = mOnItemClickListener;
    }


    public static class ViewHolder extends RecyclerView.ViewHolder {
     
        TextView tvTag, tvName;
        private CharPortraitView portrait;

        public ViewHolder(View itemView) {
     
            super(itemView);
            tvName = itemView.findViewById(R.id.name);
            portrait = itemView.findViewById(R.id.user_img);
        }
    }
    /**
     * 提供给Activity刷新数据
     * @param list
     */
    public void updateList(List<SortModel> list){
     
        this.mData = list;
        notifyDataSetChanged();
    }
    public Object getItem(int position) {
     
        return mData.get(position);
    }
    /**
     * 根据ListView的当前位置获取分类的首字母的char ascii值
     */
    public int getSectionForPosition(int position) {
     
        return mData.get(position).getLetters().charAt(0);
    }

    /**
     * 根据分类的首字母的Char ascii值获取其第一次出现该首字母的位置
     */
    public int getPositionForSection(int section) {
     
        for (int i = 0; i < getItemCount(); i++) {
     
            String sortStr = mData.get(i).getLetters();
            char firstChar = sortStr.toUpperCase().charAt(0);
            if (firstChar == section) {
     
                return i;
            }
        }
        return -1;
    }

}

item.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tag"
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:background="#ffffff"
        android:gravity="center_vertical"
        android:paddingLeft="15dp"
        android:text="A"
        android:textColor="#000000" />
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp">

        
        <com.example.lastmodel.CharPortraitView
            android:id="@+id/user_img"
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:textColor="#ffffff"
            android:layout_centerVertical="true"
            android:padding="5dp"/>
        <TextView
            android:id="@+id/name"
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:layout_marginLeft="20dp"
            android:layout_centerVertical="true"
            android:layout_toRightOf="@id/user_img"
            android:gravity="center_vertical"
            android:textSize="20sp"
            android:textColor="#000000"
            />

        <View
            android:id="@+id/view_lv_item_line"
            android:layout_width="320dp"
            android:layout_height="0.05dp"
            android:layout_below="@+id/name"
            android:layout_alignParentLeft="true"
            android:layout_alignParentEnd="true"
            android:layout_alignParentRight="true"
            android:layout_marginEnd="30dp"
            android:layout_marginRight="30dp"
            android:background="#C0C0C0"
            android:paddingBottom="15dp" />
    RelativeLayout>
LinearLayout>

SortModel.java

实体类

package com.example.lastmodel;

public class SortModel {
     
    private String telnumber;
    private String name;
    private String letters;//显示拼音的首字母



    public SortModel(String name) {
     
        this.name = name;
    }

    public SortModel(String telnumber, String name) {
     
        this.telnumber = telnumber;
        this.name = name;

    }

    public SortModel() {
         }

    public String getName() {
     
        return name;
    }

    public void setName(String name) {
     
        this.name = name;
    }

    public String getLetters() {
     
        return letters;
    }

    public void setLetters(String letters) {
     
        this.letters = letters;
    }

    @Override
    public String toString() {
     
        return "SortModel{" +
                "name='" + name + '\'' +
                ", letters='" + letters + '\'' +
                '}';
    }

}

接下来就是资源类的文件了

drawable下的

shape.xml

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <corners android:radius="20dp"/>
    <stroke android:width="1dp"
        android:color="#bcb8b8"/>
    <size android:width="320dp"
        />
    <solid android:color="#F5F5F5" />
shape>

shape_drawable.xml

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <solid android:color="@android:color/holo_red_light"/>

shape>

sidebar_background.xml

<shape android:shape="rectangle"
  xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="#ffffff"/>
    <corners
        android:topLeftRadius="8dp"
        android:bottomLeftRadius="8dp"/>
    
shape>

values下的xml文件

arrys.xml

<resources>
    <string-array name="color">
        <item>#FFBBFFitem>
        <item>#A8A8A8item>
        <item>#EEC591item>
        <item>#D8BFD8item>
        <item>#CAE1FFitem>
        <item>#BC8F8Fitem>
        <item>#CDB79Eitem>
        <item>#EEE8AAitem>
        <item>#C5C1AAitem>
        <item>#C1CDC1item>
    string-array>

resources>

attrs.xml

<resources>
    <declare-styleable name="CharPortraitView">
        <attr name="back_color" format="reference"/>
        <attr name="random" format="boolean"/>
    declare-styleable>
resources>

OK,以上就是全部的代码了，有些图片资源我没有附上去，那不太重要，可以自己找几张。仅供大家参考，若有侵权，请联系本人立即删除。