android 類似銀行卡可設定分隔符的 EditText

類似銀行卡，電話号碼的EditText控件,可以自己設定分隔符和輸入的最大長度，代碼如下

package com.xxx.xxxxxx;


import android.content.Context;
import android.text.Editable;
import android.text.InputFilter;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.widget.EditText;


/**
 * 實作輸入框輸入内容插入分隔符
 * 
 * @author yangjinbo
 * 
 */
public class DividerEditText extends EditText {


	private String lastFormatString;
	private char divideCharacter = ' ';
	private int[] formatPattern = { 4 };
	private int maxLength = 20;
	private int[] divisionPattern;


	public DividerEditText(Context context) {
		super(context);
		init();
	}


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


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


	private void init() {
		// addTextChangedListener(mInputWatcher);
		Divider u = new Divider();
		addTextChangedListener(u);
		setFilters(new InputFilter[] { u });
		divisionPattern = getDivisionPatter();
	}


	/**
	 * 字元格式化模式，例如設定為{3,4,4}，字元将要顯示成138 3800 3800的形式
	 * 
	 * @param formatPattern
	 */
	public void setFormatPattern(int maxLength,int[] formatPattern) {
		this.maxLength = maxLength;
		this.formatPattern = formatPattern;
		divisionPattern = getDivisionPatter();
	}


	public char getDividerCharacter() {
		return divideCharacter;
	}


	public int getMaxLength() {
		return maxLength;
	}


	public void setMaxLength(int maxLength) {
		this.maxLength = maxLength;
	}


	/**
	 * 設定分隔字元
	 * 
	 * @param dividerCharacter
	 */
	public void setDividerCharacter(char dividerCharacter) {
		this.divideCharacter = dividerCharacter;
	}


	private CharSequence formatText(CharSequence str) {
		int length = str.length();
		int lastInsertPos = -1;
		// 輸入的内容長度較少時，不顯示分隔符
		if (length <= formatPattern[0] + 1) {
			return deleteDivideChar(str);
		}
		CharSequence tmp = deleteDivideChar(str);
		length = tmp.length();
		StringBuilder builder = new StringBuilder();
		for (int i = 0, j = 0; i < length; i++) {
			builder.append(tmp.charAt(i));
			if (i - formatPattern[j] - lastInsertPos == 0) {
				lastInsertPos = i;
				builder.append(divideCharacter);
				if (j < formatPattern.length - 1) {
					j++;
				}
			}
		}
		if (builder.charAt(builder.length() - 1) == divideCharacter) {
			builder.deleteCharAt(builder.length() - 1);
		}
		return builder.toString();


	}


	private CharSequence deleteDivideChar(CharSequence string) {
		StringBuilder builder = new StringBuilder();
		int length = string.length();
		for (int i = 0; i < length; i++) {
			if (string.charAt(i) != divideCharacter) {
				builder.append(string.charAt(i));
			}
		}
		return builder;
	}


	/**
	 * 擷取去掉分隔符的内容
	 * 
	 * @return 去掉了分隔符的内容
	 */
	public String getRealInputText() {
		return deleteDivideChar(getText()).toString();
	}


	private int[] getDivisionPatter() {
		int len = 0;
		int i = 0;
		while (len < maxLength) {
			if (i < formatPattern.length) {
				len += formatPattern[i];
			} else {
				len += formatPattern[formatPattern.length - 1];
			}
			i++;
		}
		int[] arrayInt = new int[--i];
		arrayInt[0] = formatPattern[0];
		for (int j = 1; j < i; j++) {
			arrayInt[j] = arrayInt[j - 1];
			if (j < formatPattern.length) {
				arrayInt[j] += formatPattern[j] + 1;
			} else {
				arrayInt[j] += formatPattern[formatPattern.length - 1] + 1;
			}
		}
		return arrayInt;
	}


	final class Divider implements TextWatcher, InputFilter {
		private int deleteDivider = 0;


		public final void afterTextChanged(Editable source) {


			if (this.deleteDivider > 1) {
				int tmp = this.deleteDivider;
				this.deleteDivider = 0;
				source.delete(tmp - 1, tmp);
			}
			int j = 0;
			for (int i = 0; i < source.length(); i++) {
				char character = source.charAt(i);
				if (i == divisionPattern[j]) {
					if (j < divisionPattern.length - 1) {
						j++;
					}
					if (character != divideCharacter) {
						source.insert(i, String.valueOf(divideCharacter));
					}
				} else if (character == divideCharacter) {
					source.delete(i, i + 1);
					i--;
				}
			}
		}


		public final void beforeTextChanged(CharSequence paramCharSequence,
				int paramInt1, int paramInt2, int paramInt3) {
		}


		public final void onTextChanged(CharSequence paramCharSequence,
				int paramInt1, int paramInt2, int paramInt3) {
		}


		public final CharSequence filter(CharSequence source, int start,
				int end, Spanned dest, int dstart, int dend) {


			if (deleteDivideChar(
					new SpannableStringBuilder(dest).replace(dstart, dend,
							source, start, end).toString()).length() > maxLength)
				return "";
			SpannableStringBuilder result = new SpannableStringBuilder(source);
			int[] arrayOfInt = divisionPattern;
			int dLength = dend - dstart;
			for (int i = 0; i < arrayOfInt.length; i++) {
				if ((source.length() == 0) && (dstart == arrayOfInt[i])
						&& (dest.charAt(dstart) == divideCharacter)) {
					this.deleteDivider = arrayOfInt[i];
				}
				int j;
				if ((dstart - dLength <= arrayOfInt[i])
						&& (dstart + end - dLength >= arrayOfInt[i])
						&& (((j = arrayOfInt[i] - dstart) == end) || ((j >= 0)
								&& (j < end) && (result.charAt(j) != divideCharacter)))) {
					result.insert(j, String.valueOf(divideCharacter));
					end++;
				}
			}
			return result;
		}
	}
}