Android一个自定义验证码的实现

<declare-styleable name="CodeView">
<attr name="count" format="integer"/>
<attr name="line" format="integer"/>
<attr name="font_color" format="color|reference"/>
<attr name="font_size" format="dimension|reference"/>
</declare-styleable>

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import com.customerview.wuweilong.customerview.R;
import java.util.Random;

/**
* Created by wwl on 2016/4/11.
* 验证码
*/
public class CodeView extends View{
private int DEFAULT_COUNT = 4;//默认数字个数
private int DEFAULT_LINE = 50;//默认干扰线条数
private int DEFAULT_COLOR = Color.RED;//默认字体颜色
private int DEFAULT_FONT_SIZE = 18;//默认字体大小sp

private int count;
private int line_count;
private int font_color;
private int font_size;
private Random rmd;
private Paint mPaint;
private String code;

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

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

public CodeView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
TypedArray a = context.obtainStyledAttributes(attrs,R.styleable.CodeView);
font_color = a.getColor(R.styleable.CodeView_font_color,DEFAULT_COLOR);
font_size = a.getDimensionPixelSize(R.styleable.CodeView_font_size,
(int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, DEFAULT_FONT_SIZE, getResources().getDisplayMetrics()));
count = a.getInt(R.styleable.CodeView_count, DEFAULT_COUNT);
line_count = a.getInt(R.styleable.CodeView_line, DEFAULT_LINE);

rmd = new Random();
mPaint = new Paint();

code = getCode();
initPaint();
}
//获取验证码
private String getCode(){
String code = "";
for (int i = 0 ; i < count; i++){
code += rmd.nextInt(10);
}
return code;
}
//初始化paint
private void initPaint(){
//        mPaint.reset();
mPaint.setAntiAlias(true);
mPaint.setColor(font_color);
mPaint.setTextSize(font_size);
}
//计算宽度
private int measureWidth(int widthMeasureSpec){
int mode = MeasureSpec.getMode(widthMeasureSpec);
int width = MeasureSpec.getSize(widthMeasureSpec);
if (mode == MeasureSpec.EXACTLY){
return width;
}else if(mode == MeasureSpec.AT_MOST){
return getPaddingLeft()+getRect().width()+getPaddingRight();
}
return  0;
}
//计算高度
private int measureHeght(int heightMeasureSpec){
int mode = MeasureSpec.getMode(heightMeasureSpec);
int height = MeasureSpec.getSize(heightMeasureSpec);
if (mode == MeasureSpec.EXACTLY){
return height;
}else if (mode == MeasureSpec.AT_MOST){
return getPaddingTop()+getRect().height()+getPaddingBottom();
}
return  0 ;
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int width = measureWidth(widthMeasureSpec);
int height = measureHeght(heightMeasureSpec);
setMeasuredDimension(width, height);
}

@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int width = getMeasuredWidth();
int height = getMeasuredHeight();
Rect rect = new Rect(0,0,width,height);

//绘制外围矩形框
Rect rect1 = new Rect(rect);
rect1.inset(2,2);
mPaint.setStyle(Paint.Style.FILL);
mPaint.setStrokeWidth(1);
mPaint.setColor(0xff00ffff);
canvas.drawRect(rect1, mPaint);
mPaint.setStyle(Paint.Style.FILL);

//绘制随机干扰线
mPaint.setColor(Color.GRAY);
for (int i = 0 ; i < line_count;i++){
int startX = rmd.nextInt(width);
int startY = rmd.nextInt(height);
int stopX = rmd.nextInt(width);
int stopY = rmd.nextInt(height);
canvas.drawLine(startX,startY,stopX,stopY,mPaint);

}

//绘制文字
mPaint.setColor(font_color);
Rect textRect = getRect();
Paint.FontMetrics fontMetrics = mPaint.getFontMetrics();
int x = (width - textRect.width())/2;
int y = (int)(height/2+(fontMetrics.descent-fontMetrics.ascent)/2-fontMetrics.descent);
canvas.drawText(code,x,y,mPaint);
}

//获取字体所占的区域
private Rect getRect(){
Rect rect = new Rect();
mPaint.getTextBounds(code,0,code.length(),rect);
return rect;
}

//刷新验证码
public void refresh(){
code = getCode();
invalidate();//重新ondraw
}
//获取验证码
public String getTheCode(){
return code;
}
//判断用户输入验证码是否正确
public boolean isRigth(String inputCode){
if (inputCode == null)
return false;
if (inputCode.equals(code))
return true;
return false;
}
}

<com.customerview.wuweilong.customerview.view.CodeView
android:id="@+id/codeView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10dp"
wwl:count="5"
wwl:font_color="#00ff00"
wwl:font_size="24sp"
wwl:line="50"
/>

codeView = (CodeView) findViewById(R.id.codeView);
refreshBtn = (Button) findViewById(R.id.refresh_btn);
refreshBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(CodeViewActivity.this,"上一个验证码是"+codeView.getTheCode(),Toast.LENGTH_SHORT).show();
codeView.refresh();
}
});

editText = (EditText) findViewById(R.id.edit_text);
editText.setOnEditorActionListener(new TextView.OnEditorActionListener() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
String inputCode = editText.getText().toString().trim();
String result;
result = codeView.isRigth(inputCode) ? "right" : "false";
Toast.makeText(CodeViewActivity.this, result, Toast.LENGTH_SHORT).show();
return true;
}
});