转载请标明出处：http://blog.csdn.net/goldenfish1919/article/details/44418883
先看一下我们要做的效果：
价格分成了3部分。前面是一个￥，中间的整数部分，后面的小数部分，中间还带一个删除线。
參考：http://blog.csdn.net/lmj623565791/article/details/44098729，我们这个事实上更简单，自己定义一个view。然后把三个部分和删除线分别画出来就能够了。
PriceView.java：
public class PriceView extends View{
private String value = null;
private int moneySize = -1;
private int intSize = -1;
private int decimalSize = -1;
private String money = "￥";
private String decimalPart = "";
private String intPart = "";
private int moneyStart = 0;
private int intStart = 0;
private int decimalStart = 0;
private int textColor = 0;
private boolean strike = false;
private boolean withEndZero = true;
private Paint mPaint;
private Rect mTextBound = new Rect();
private int totalWidth = 0;
private int maxHeight = 0;
private boolean hasComma = false;
public PriceView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context, attrs);
}
public PriceView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public PriceView(Context context) {
this(context, null);
}
public void setText(String text){
this.value = text;
calcTextDimens();
}
private void init(Context context, AttributeSet attrs){
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
getProperties(context, attrs);
calcTextDimens();
}
private void calcTextDimens() {
totalWidth = 0;
maxHeight = 0;
//把text分成三个部分
if(value == null || value.length() <= 0){
return;
}
String arr[] = value.split("\\.");
//整数部分
intPart = arr[0];
if(intPart.length() > 0 && intPart.charAt(0) == '￥'){
intPart = intPart.substring(1);
}
if(intPart.indexOf(",") >= 0){
hasComma = true;
}else{
hasComma = false;
}
//小数部分
decimalPart = arr.length > 1?
arr[1]:"";
if(decimalPart != null){
if(!withEndZero){
decimalPart = decimalPart.replaceAll("0{1,}$", "");
}
if(decimalPart != null && decimalPart.length() > 0){
decimalPart = "."+decimalPart;
}
}
//处理￥
int moneyWidth = process(money, moneySize);
moneyStart = getPaddingLeft();
//处理整数部分
int intWidth = process(intPart, intSize);
intStart = moneyStart + moneyWidth;
//处理小数部分
process(decimalPart, decimalSize);
decimalStart = intStart + intWidth;
totalWidth += getPaddingLeft() + getPaddingRight();
maxHeight += getPaddingTop() + getPaddingBottom();
}
private int process(String text, int textSize){
if(text == null || text.length() <= 0){
return 0;
}
mPaint.setTextSize(textSize);
int textWidth = (int) mPaint.measureText(text);
mPaint.getTextBounds(text, 0, text.length(), mTextBound);
totalWidth += textWidth;
maxHeight = mTextBound.height() > maxHeight?
mTextBound.height() : maxHeight;
return textWidth;
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
int width = measureWidth(widthMeasureSpec);
int height = measureHeight(heightMeasureSpec);
setMeasuredDimension(width, height);
}
protected void onDraw(Canvas canvas)
{
super.onDraw(canvas);
mPaint.setColor(textColor);
//画中间的删除线
if(strike){
//mPaint.setFlags(Paint.STRIKE_THRU_TEXT_FLAG);是不能够的。为什么不能够能够自己试一下
float startX = getPaddingLeft();
float startY = (getMeasuredHeight() - getPaddingBottom() - getPaddingTop()) /2 + getPaddingTop();
float stopX = getMeasuredWidth() - getPaddingRight();
float stopY = startY;
canvas.drawLine(startX, startY , stopX, stopY, mPaint);
}
int y = getMeasuredHeight() - getPaddingBottom();
if(hasComma){
y -= dp2px(getContext(), 3);
}
//画￥
mPaint.setTextSize(moneySize);
canvas.drawText(money, moneyStart, y, mPaint);
//画整数部分
mPaint.setTextSize(intSize);
canvas.drawText(intPart, intStart, y, mPaint);
//画小数部分
mPaint.setTextSize(decimalSize);
canvas.drawText(decimalPart, decimalStart, y, mPaint);
}
private int measureWidth(int measureSpec)
{
int mode = MeasureSpec.getMode(measureSpec);
int val = MeasureSpec.getSize(measureSpec);
int result = 0;
switch (mode){
case MeasureSpec.EXACTLY:
result = val;
break;
case MeasureSpec.AT_MOST:
case MeasureSpec.UNSPECIFIED:
result = totalWidth;
break;
}
return result;
}
private int measureHeight(int measureSpec)
{
int mode = MeasureSpec.getMode(measureSpec);
int val = MeasureSpec.getSize(measureSpec);
int result = 0;
switch (mode){
case MeasureSpec.EXACTLY:
result = val;
break;
case MeasureSpec.AT_MOST:
case MeasureSpec.UNSPECIFIED:
result = maxHeight;
break;
}
return result;
}
private void getProperties(Context context, AttributeSet attrs){
//自己定义的属性
TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CartPriceValue);
int textSize = a.getDimensionPixelSize(R.styleable.CartPriceValue_textSize, 14);
String value = a.getString(R.styleable.CartPriceValue_value);
int textColor = a.getColor(R.styleable.CartPriceValue_textColor, 0xffffff);
int moneySize = a.getDimensionPixelSize(R.styleable.CartPriceValue_moneySize, textSize);
int intSize = a.getDimensionPixelSize(R.styleable.CartPriceValue_intSize, textSize);
int decimalSize = a.getDimensionPixelSize(R.styleable.CartPriceValue_decimalSize, textSize);
boolean strike = a.getBoolean(R.styleable.CartPriceValue_strike, false);
boolean withEndZero = a.getBoolean(R.styleable.CartPriceValue_withEndZero, true);
this.value = value;
this.textColor = textColor;
this.moneySize = moneySize;
this.intSize = intSize;
this.decimalSize = decimalSize;
this.strike = strike;
this.withEndZero = withEndZero;
a.recycle();
}
public static int px2dp(Context context, float pxValue) {
final float scale = context.getResources().getDisplayMetrics().density;
return (int) (pxValue / scale + 0.5f);
}
public static int dp2px(Context context, float dpValue) {
final float scale = context.getResources().getDisplayMetrics().density;
return (int) (dpValue * scale + 0.5f);
}
}
attr.xml：
<?xml version="1.0" encoding="utf-8"?>
<resources> <declare-styleable name="CartPriceValue">
<attr name="value" format="reference|string" />
<attr name="textColor" format="reference|color" />
<attr name="textSize" format="reference|dimension" />
<attr name="moneySize" format="reference|dimension" />
<attr name="intSize" format="reference|dimension" />
<attr name="decimalSize" format="reference|dimension" />
<attr name="strike" format="boolean" />
<attr name="withEndZero" format="boolean" />
</declare-styleable> </resources>
布局文件main.xml:
<? xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:cart="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white"
android:orientation="vertical" > <com.example.priceview.PriceView
android:id="@+id/priceview1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
cart:value="￥12.345"
cart:moneySize="14dp"
cart:intSize="20dp"
cart:decimalSize="16dp"
cart:textColor="#ff0000"
cart:strike="true"
android:padding="10dp"/> <com.example.priceview.PriceView
android:id="@+id/priceview2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
cart:value="￥12.0"
cart:moneySize="14dp"
cart:intSize="20dp"
cart:decimalSize="16dp"
cart:textColor="#ff0000"
cart:strike="true"
android:padding="10dp"/> <com.example.priceview.PriceView
android:id="@+id/priceview3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
cart:value="￥12.0"
cart:moneySize="14dp"
cart:intSize="20dp"
cart:decimalSize="16dp"
cart:textColor="#ff0000"
cart:strike="true"
cart:withEndZero="false"/> </LinearLayout>
project源代码下载：http://download.csdn.net/download/goldenfish1919/8512713
ps:
（1）在一个ListView中使用这个PriceView的时候，发现有的时候价格被截断没有展示出来，后来才发现是由于Listview中的View复用导致的。
因此须要在setText()中显式的调用一下requestLayout()。它会导致又一次调用onMeasure()。
（2）后来又发现个问题，当整数部分带有逗号的时候，逗号会显示不全，不知道是哪块代码出的问题。有大神不吝赐教下吗？