Android自定义View实现随机验证码

<?xml version="1.0" encoding="utf-8"?><resources> <attr name="textColor" format="color"/> <attr name="textContent" format="string"/> <attr name="textSize" format="dimension"/> <declare-styleable name="VerificationCodeView"> <attr name="textContent" /> <attr name="textColor" /> <attr name="textSize" /> </declare-styleable></resources>

public class VerificationCodeView extends View { /** * 文本 */ private String mTitleText; /** * 文本的颜色 */ private int mTextColor; /** * 文本的大小 */ private int mTextSize; /** * 绘制时控制文本绘制的范围 */ private Rect mBound; /** * 初始化画笔 */ private Paint mTextPaint; private Paint mPointPaint; private Paint mPathPaint; /** * 干扰点坐标的集合 */ private ArrayList<PointF> mPoints = new ArrayList<PointF>(); /** * 绘制贝塞尔曲线的路径集合 */ private ArrayList<Path> mPaths = new ArrayList<Path>(); public VerificationCodeView(Context context) { this(context, null); } public VerificationCodeView(Context context, AttributeSet attributeSet) { this(context, attributeSet, 0); } public VerificationCodeView(Context context, AttributeSet attributeSet, int defStyle) { super(context, attributeSet, defStyle); TypedArray typedArray = context.getTheme().obtainStyledAttributes(attributeSet, R.styleable.VerificationCodeView, defStyle, 0); int size = typedArray.getIndexCount(); for (int i = 0; i < size; i++) {  int content = typedArray.getIndex(i);  switch (content) {  case R.styleable.VerificationCodeView_textContent:   mTitleText = typedArray.getString(content);   break;  case R.styleable.VerificationCodeView_textColor:   mTextColor = typedArray.getColor(content, Color.BLACK);   break;  case R.styleable.VerificationCodeView_textSize:   // 默认设置为16sp，TypeValue也可以把sp转化为px   mTextSize = typedArray.getDimensionPixelSize(content, (int) TypedValue.applyDimension(    TypedValue.COMPLEX_UNIT_SP, 16, getResources().getDisplayMetrics()));   break;  } } typedArray.recycle(); //设置点击事件变换数字 this.setOnClickListener(new OnClickListener() {  @Override  public void onClick(View v) {  mTitleText = randomText();  postInvalidate();  } }); } /** * EXACTLY：一般是设置了明确的值或者是MATCH_PARENT * AT_MOST：表示子布局限制在一个最大值内，一般为WARP_CONTENT * UNSPECIFIED：表示子布局想要多大就多大，很少使用 * * @param widthMeasureSpec * @param heightMeasureSpec */ @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); int widthMode = MeasureSpec.getMode(widthMeasureSpec); int widthSize = MeasureSpec.getSize(widthMeasureSpec); int heightMode = MeasureSpec.getMode(heightMeasureSpec); int heightSize = MeasureSpec.getSize(heightMeasureSpec); //用来设置要画的布局的大小 if (widthMode != MeasureSpec.EXACTLY) {  widthSize = (int) (getPaddingLeft() + mBound.width() + getPaddingRight()); } if (heightMode != MeasureSpec.EXACTLY) {  heightSize = (int) (getPaddingTop() + mBound.height() + getPaddingBottom()); } setMeasuredDimension(widthSize, heightSize); } @Override protected void onDraw(Canvas canvas) { //生成随机的背景颜色 mTextPaint.setColor(Color.YELLOW); canvas.drawRect(0, 0, getMeasuredWidth(), getMeasuredHeight(), mTextPaint); //生成随机的文字颜色 mTextPaint.setColor(mTextColor); //将文字画在布局的中间 canvas.drawText(mTitleText, getWidth() / 2 - mBound.width() / 2, getHeight() / 2 + mBound.height() / 2, mTextPaint); } /** * 生成随机的四位数字验证码 * * @return */ private String randomText() { Random random = new Random(); Set<Integer> set = new HashSet<Integer>(); while (set.size() < 4) {  int randomInt = random.nextInt(10);  set.add(randomInt); } StringBuffer sb = new StringBuffer(); for (Integer i : set) {  sb.append("" + i); } return sb.toString(); }}

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:verification="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center" > <com.example.aotuman.verification.view.VerificationCodeView android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingTop="10dp" android:paddingBottom="10dp" android:paddingLeft="10dp" android:paddingRight="10dp" verification:textContent="3712" verification:textColor="#ff0000" verification:textSize="40sp" /></RelativeLayout>

@Override protected void onDraw(Canvas canvas) { initData(); Random mRandom = new Random(); //生成随机的背景颜色 mTextPaint.setARGB(255, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20); canvas.drawRect(0, 0, getMeasuredWidth(), getMeasuredHeight(), mTextPaint); //生成随机的文字颜色 mTextPaint.setARGB(255, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20); //将文字画在布局的中间 canvas.drawText(mTitleText, getWidth() / 2 - mBound.width() / 2, getHeight() / 2 + mBound.height() / 2, mTextPaint); // 产生干扰效果1 -- 干扰点 for (PointF pointF : mPoints) {  mPointPaint.setARGB(255, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20);  canvas.drawPoint(pointF.x, pointF.y, mPointPaint); } // 产生干扰效果2 -- 干扰线 for (Path path : mPaths) {  mPathPaint.setARGB(255, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20, mRandom.nextInt(200) + 20);  canvas.drawPath(path, mPathPaint); } private void initData() { Random mRandom = new Random(); // 获取控件的宽和高，此时已经测量完成 int mHeight = getHeight(); int mWidth = getWidth(); mPoints.clear(); // 生成干扰点坐标 for (int i = 0; i < 150; i++) {  PointF pointF = new PointF(mRandom.nextInt(mWidth) + 10, mRandom.nextInt(mHeight) + 10);  mPoints.add(pointF); } mPaths.clear(); // 生成干扰线坐标 for (int i = 0; i < 2; i++) {  Path path = new Path();  int startX = mRandom.nextInt(mWidth / 3) + 10;  int startY = mRandom.nextInt(mHeight / 3) + 10;  int endX = mRandom.nextInt(mWidth / 2) + mWidth / 2 - 10;  int endY = mRandom.nextInt(mHeight / 2) + mHeight / 2 - 10;  path.moveTo(startX, startY);  path.quadTo(Math.abs(endX - startX) / 2, Math.abs(endY - startY) / 2, endX, endY);  mPaths.add(path); } } private void init() { // 初始化文字画笔 /**  * 获得绘制文本的宽和高  */ mTextPaint = new Paint(); mTextPaint.setTextSize(mTextSize); mBound = new Rect(); //获取到的存在mBound里面 mTextPaint.getTextBounds(mTitleText, 0, mTitleText.length(), mBound); // 初始化干扰点画笔 mPointPaint = new Paint(); mPointPaint.setStrokeWidth(6); mPointPaint.setStrokeCap(Paint.Cap.ROUND); // 设置断点处为圆形 // 初始化干扰线画笔 mPathPaint = new Paint(); mPathPaint.setStrokeWidth(5); mPathPaint.setColor(Color.GRAY); mPathPaint.setStyle(Paint.Style.STROKE); // 设置画笔为空心 mPathPaint.setStrokeCap(Paint.Cap.ROUND); // 设置断点处为圆形 }