银行卡格式化(每四位空格,删除添加,更变等)

输入时候动态的让银行卡格式化

1.目前已知长按粘贴会有部分bug, 暂时没有解决, 统一处理是把光标放到最后.

2.无法长按删除, 猜测是 format(String.valueOf(editable)); 方法后删除按钮的焦点消失, 暂时没解决.

/**
 * 选中一个粘贴一个(光标停留在粘贴元素最后一个)
 * 选中一个删除 (光标停留在删除掉的元素的start位置)
 * 选中一个粘贴多个(光标停留在粘贴元素最后一个)
 *
 * 选中多个粘贴相同数量 (光标停留在粘贴元素最后一个)
 * 选中多个粘贴少量(光标停留在粘贴元素最后一个)
 * 选中多个粘贴更多(光标停留在粘贴元素最后一个)
 */

/**
 * Created by sqj on 2017/12/5.
 */

public class BankIDFormatEditText extends EditText {
    String space = " ";
    private boolean shouldStopChange = false;
    private int textOnViewLength;
    private String mTextBefore;
    private String mTextAfter;
    private int mStartPosition;
    private int mEndPosition;

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

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

    public BankIDFormatEditText(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        setFocusable(true);
        setEnabled(true);
        setFocusableInTouchMode(true);
        addTextChangedListener(new BandCardWatcher());

    }

    private class BandCardWatcher implements TextWatcher {

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            if (shouldStopChange) {
            } else {
                mTextBefore = String.valueOf(s);
                mStartPosition = getSelectionStart();
                mEndPosition = getSelectionEnd();
                // 第一次改变后总长度(手输)
                mBeforeChangeLength = s.toString().length();

            }
        }

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
//            Log.d("BandCardWatcher", "onTextChanged:" + s);
        }

        @Override
        public void afterTextChanged(Editable editable) {
            if (shouldStopChange) {
                shouldStopChange = false;
                return;
            }
            shouldStopChange = true;

            mTextAfter = String.valueOf(editable);
            if (mStartPosition!=mEndPosition){// 这是长按选中的状态
                format(editable);
                setSelection(textOnViewLength);
            }else {
                if (mTextBefore.length() < mTextAfter.length()) {// 增加

                    format(editable);
                    if ((mStartPosition + 1) % 5 == 0) {
                        if (mStartPosition != 0) {
                            setSelection(mStartPosition + 2);
                        }
                    } else {
                        setSelection(mStartPosition + 1);
                    }
                } else if (mTextBefore.length() > mTextAfter.length()) { // 减少

                    if (mStartPosition % 5 == 0) {
                        if (mStartPosition != 0) {
                            // 光标在空格后面点删除的情况
                            editable.replace(mStartPosition - 2, mStartPosition - 1, " ");
                        }
                    }

                    format(editable);
                    if (mStartPosition != 1 && (mStartPosition - 1) % 5 == 0) {
                        setSelection(mStartPosition - 2);
                    } else if (mStartPosition != 0) {
                        setSelection(mStartPosition - 1);
                    }


                } else if (mTextBefore.length() == mTextAfter.length()) {// 替换

                    format(editable);
                    setSelection(mStartPosition);
                }
            }



        }
    }


    private void format(Editable editable) {

        String str = editable.toString().trim().replaceAll(space, "");
        int len = str.length();
        int courPos;

        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < len; i++) {

            if (i % 4 == 0 && i != 0) {
                builder.append(space);
                builder.append(str.charAt(i));
            } else {
                builder.append(str.charAt(i));
            }
        }
        courPos = builder.length();
        textOnViewLength = builder.toString().length();
        setText(builder.toString());


    }

}