AndroidView教程之自定义验证码输入框效果

/**
 * 验证码输入框,重写EditText的绘制方法实现。
 * @author RAE
 */
public class CodeEditText extends AppCompatEditText {
 
 // 验证码文本颜色
 private int mTextColor;
 // 输入的最大长度
 private int mMaxLength = 4;
 // 边框宽度
 private int mStrokeWidth;
 // 边框高度
 private int mStrokeHeight;
 // 边框之间的距离
 private int mStrokePadding = 20;
 // 用矩形来保存方框的位置、大小信息
 private final Rect mRect = new Rect();
 // 方框的背景
 private Drawable mStrokeDrawable;

 /**
 * 构造方法
 *
 */
 public CodeEditText(Context context, AttributeSet attrs) {
 super(context, attrs);
 TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.CodeEditText);
 int indexCount = typedArray.getIndexCount();
 for (int i = 0; i = 0) {
  setFilters(new InputFilter[]{new InputFilter.LengthFilter(maxLength)});
 } else {
  setFilters(new InputFilter[0]);
 }
 }
}

 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
 super.onMeasure(widthMeasureSpec, heightMeasureSpec);
 // 当前输入框的宽高信息
 int width = getMeasuredWidth();
 int height = getMeasuredHeight();
 int widthMode = MeasureSpec.getMode(widthMeasureSpec);
 int heightMode = MeasureSpec.getMode(heightMeasureSpec);

 // 判断高度是否小于推荐高度
 if (height 

 @Override
 protected void onDraw(Canvas canvas) {
  // 在画支持设置文本颜色，把系统化的文本透明掉，相当于覆盖
  mTextColor = getCurrentTextColor();
  setTextColor(Color.TRANSPARENT);
  // 系统画的方法
  super.onDraw(canvas);
  // 重新设置文本颜色
  setTextColor(mTextColor);
  // 重绘背景颜色
  drawStrokeBackground(canvas);
  // 重绘文本
  drawText(canvas);
 }

 /**
  * 绘制方框
  */
 private void drawStrokeBackground(Canvas canvas) {
  // 下面绘制方框背景颜色
  // 确定反馈位置
  mRect.left = 0;
  mRect.top = 0;
  mRect.right = mStrokeWidth;
  mRect.bottom = mStrokeHeight;
  int count = canvas.getSaveCount(); // 当前画布保存的状态
  canvas.save(); // 保存画布
  for (int i = 0; i 

 /**
  * 重绘文本
  */
 private void drawText(Canvas canvas) {
  int count = canvas.getSaveCount();
  canvas.translate(0, 0);
  int length = getEditableText().length();
  for (int i = 0; i 

 @Override
 protected void onTextChanged(CharSequence text, int start,
         int lengthBefore, int lengthAfter) {
  super.onTextChanged(text, start, lengthBefore, lengthAfter);

  // 当前文本长度
  int textLength = getEditableText().length();

  if (textLength == mMaxLength) {
   hideSoftInput();
   if (mOnInputFinishListener != null) {
    mOnInputFinishListener.onTextFinish(getEditableText().toString(), mMaxLength);
   }
  }

 }