自动格式手机号、银行卡的EditText

依照产品需求当用户输入手机号，银行卡是能自动格式化（添加分隔符），方便用户输入、阅读；同时手机号输入不能超过11位，银行卡不超过19位；
依照产品的需求定制一个简单的EditText，基于系统EditText 扩展一个自己的控件；
先上最后的效果,图片太大加载不出来，压缩了一下有点丢帧：

edittext.gif

1. 既然是基于EditText 扩展，那就直接继承系统控件，同时要支持输入手机号、银行卡，那就需要自定义输入框的类型，这里自定义枚举类型

<declare-styleable name="PatternEditText">
        <attr name="Format_Type" format="enum">
            <enum name="mobile_phone" value="1"/>
            <enum name="bank_card" value="2"/>
        </attr>
</declare-styleable>

那么在控件初始化的时候读取XML中配置的属性，就可以更加不同的类型，在不同的位置分隔；

企业微信截图_15525508201553.png

public class PatternEditText extends android.support.v7.widget.AppCompatEditText {

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

    public PatternEditText(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public PatternEditText(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        TypedArray typedArray = context.getTheme().obtainStyledAttributes(attrs, R.styleable.PatternEditText, defStyleAttr, 0);
        inputType = typedArray.getString(R.styleable.PatternEditText_Format_Type);//读取配置的类型
        typedArray.recycle();
        init();
    }
}

2.初始化一些基本的属性，设置只可以输入数字

private void init() {
        shouldStopChange = false;
        setInputType(InputType.TYPE_CLASS_NUMBER);
        setFocusable(true);
        setEnabled(true);
        setFocusableInTouchMode(true);
        setCursorVisible(true);
        addTextChangedListener(watcher);
       
}

3.格式化（插入分隔符）可以在用户输入后，可以对改控件添加addTextChangedListener监听，在afterTextChanged中处理，逻辑很简单，直接贴代码了：

private TextWatcher watcher = new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void afterTextChanged(Editable editable) {
            format();
        }
    };

    private void format() {
        if (!TextUtils.isEmpty(getText().toString())){
            String value = getText().toString();
            if (!TextUtils.isEmpty(value) && value.length() > inputMaxLength){
                value = value.substring(0, inputMaxLength);
            }
            if (shouldStopChange) {
                shouldStopChange = false;
                return;
            }
            shouldStopChange = true;

            StringBuffer inputValue = new StringBuffer(value);
            int selectionStart = getSelectionStart();
            for (int i = 0; i < inputValue.length(); i++) {
                char charAt = inputValue.charAt(i);
                if (charAt == WHITE_SPACE) {
                    inputValue.delete(i, i + 1);
                    if (i < selectionStart) {
                        selectionStart--;
                    }
                    i--;
                } else if ((i-fristWhiteSpacePosition) % white_space_step == 0) {
                    inputValue.insert(i, WHITE_SPACE);
                    if (i < selectionStart) {
                        selectionStart++;
                    }
                }
            }
            setText(inputValue);
            setSelection(Math.min(inputValue.length(), selectionStart));
        }
    }

逻辑比较简单，总共就100行代码，统一整理如下：

import android.content.Context;
import android.content.res.TypedArray;
import android.text.Editable;
import android.text.InputType;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.View;

import com.dachuan.R;


/**
 * Created by admin on 2019/3/13.
 */

public class PatternEditText extends android.support.v7.widget.AppCompatEditText {

    private String inputType = "1";//默认手机格式
    private static final char WHITE_SPACE = ' ';//空格
    private boolean shouldStopChange = false;
    private int inputMaxLength;
    private int phoneLength = 11;//手机号码长度
    private int phoneFristSpacePosition = 3;//手机号第一个空格位置
    private int bankNumLength = 19;//银行卡最大长度
    private int bankNumFristSpacePosition = 4;//银行卡第一个空格位置
    private int white_space_step = 5;//空格间隔

    private int fristWhiteSpacePosition;

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

    public PatternEditText(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public PatternEditText(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        TypedArray typedArray = context.getTheme().obtainStyledAttributes(attrs, R.styleable.PatternEditText, defStyleAttr, 0);
        inputType = typedArray.getString(R.styleable.PatternEditText_Format_Type);
        typedArray.recycle();
        init();
    }

    private void init() {
        shouldStopChange = false;
        setInputType(InputType.TYPE_CLASS_NUMBER);
        setFocusable(true);
        setEnabled(true);
        setFocusableInTouchMode(true);
        setCursorVisible(true);
        addTextChangedListener(watcher);
        initInputType();
        format();
    }

    private void initInputType() {
        if ("1".equals(inputType)){
            inputMaxLength = phoneLength + 2;
            fristWhiteSpacePosition = phoneFristSpacePosition;
        }else {
            inputMaxLength = bankNumLength + 4;
            fristWhiteSpacePosition = bankNumFristSpacePosition;
        }
    }


    private TextWatcher watcher = new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void afterTextChanged(Editable editable) {
            format();
        }
    };

    private void format() {
        if (!TextUtils.isEmpty(getText().toString())){
            String value = getText().toString();
            if (!TextUtils.isEmpty(value) && value.length() > inputMaxLength){
                value = value.substring(0, inputMaxLength);
            }
            if (shouldStopChange) {
                shouldStopChange = false;
                return;
            }
            shouldStopChange = true;

            StringBuffer inputValue = new StringBuffer(value);
            int selectionStart = getSelectionStart();
            for (int i = 0; i < inputValue.length(); i++) {
                char charAt = inputValue.charAt(i);
                if (charAt == WHITE_SPACE) {
                    inputValue.delete(i, i + 1);
                    if (i < selectionStart) {
                        selectionStart--;
                    }
                    i--;
                } else if ((i-fristWhiteSpacePosition) % white_space_step == 0) {
                    inputValue.insert(i, WHITE_SPACE);
                    if (i < selectionStart) {
                        selectionStart++;
                    }
                }
            }
            setText(inputValue);
            setSelection(Math.min(inputValue.length(), selectionStart));
        }
    }
}