Android一个自定义验证码的实现

1、在values文件夹下新建attrs.xml文件，添加属性：

<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>

2、写一个类继承View

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;    }}

3、使用

<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;    }});