private int downColor = Color.parseColor("#00ff00");
private Paint errorPaint;
private int errorColor = Color.parseColor("#ff0000");
private Paint linePressPaint;
private float arrowHeight = 20;
private int angle = 30;
private onTouchResult mOnTouchResult;
private boolean isWrongFlag = false;
private boolean isPressFlag = false;
public selfNineView(Context context) {
this(context, null);
}
public selfNineView(Context context, @Nullable AttributeSet attrs) {
this(context, attrs, 0);
}
public selfNineView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
mSelectData = new ArrayList<>();
normalPaint = initPaint(normalColor);
downPaint = initPaint(downColor);
errorPaint = initPaint(errorColor);
linePressPaint = initPaint(downColor);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
@Override
protected void onDraw(Canvas canvas) {
if (!initFlag) {
initCell();
initFlag = true;
}
drawCircle(canvas);
drawLine(canvas);
}
//绘制两个点之间的连线以及箭头
private void drawLine(Canvas canvas) {
if (mSelectData != null && mSelectData.size() != 0) {
// System.out.println(mSelectData.size());
myPoint lastPoint = mSelectData.get(0);
if (isWrongFlag){
linePressPaint.setColor(errorColor);
}else {
linePressPaint.setColor(downColor);
}
for (int i = 1; i < mSelectData.size(); i++) {
myPoint curPoint = mSelectData.get(i);
float d = (float) twoPointDistace(lastPoint.x, lastPoint.y, curPoint.x, curPoint.y);
float cos_a = (curPoint.x - lastPoint.x) * 1.0f / d;
float sin_a = (curPoint.y - lastPoint.y) * 1.0f / d;
canvas.drawLine(lastPoint.x + inCircleR cos_a, lastPoint.y + inCircleR sin_a,
curPoint.x - inCircleR cos_a, curPoint.y - inCircleR sin_a, linePressPaint);
//绘制箭头
drawArrow(lastPoint.x, lastPoint.y, d, cos_a, sin_a, canvas);
lastPoint = curPoint;
}
if (isPressFlag){
//绘制射线
float d = (float) twoPointDistace(lastPoint.x, lastPoint.y, downPointX, downPointY);
float cos_a = (downPointX - lastPoint.x) * 1.0f / d;
float sin_a = (downPointY - lastPoint.y) * 1.0f / d;
canvas.drawLine(lastPoint.x + inCircleR cos_a, lastPoint.y + inCircleR sin_a,
downPointX, downPointY, linePressPaint);
}
}
}
private void drawArrow(float startX, float startY, float d, float cos_a, float sin_a, Canvas canvas) {
float l = (float) (arrowHeight * (Math.tan(Math.toRadians(angle))));
float x0 = startX + (d - outCircleR - arrowHeight) * cos_a;
float y0 = startY + (d - outCircleR - arrowHeight) * sin_a;
float x1 = startX + (d - outCircleR) * cos_a;
float y1 = startY + (d - outCircleR) * sin_a;
float x2 = x0 + l * sin_a;
float y2 = y0 - l * cos_a;
float x3 = x0 - l * sin_a;
float y3 = y0 + l * cos_a;
Path path = new Path();
path.moveTo(x1, y1);
path.lineTo(x2, y2);
path.lineTo(x3, y3);
path.close();
linePressPaint.setStyle(Paint.Style.FILL);
canvas.drawPath(path, linePressPaint);
}
private double twoPointDistace(float startX, float startY, float endX, float endY) {
return Math.sqrt(Math.pow(startX - endX, 2) + Math.pow(startY - endY, 2));
}
@Override
public boolean onTouchEvent(MotionEvent event) {
downPointX = event.getX();
downPointY = event.getY();
System.out.println(event.getAction());
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
isPressFlag = true;
for (int i = 0; i < mPointData.size(); i++) {
myPoint currentPoint = mPointData.get(i);
if (checkIsInCircle(downPointX, downPointY, currentPoint.x, currentPoint.y, outCircleR)) {
//记录按下的那个点，等下要以密码的形式返回出去
mSelectData.add(currentPoint);
currentPoint.state = myPoint.STATE_DOWN;
}
}
invalidate();
break;
case MotionEvent.ACTION_MOVE:
for (int i = 0; i < mPointData.size(); i++) {
myPoint currentPoint = mPointData.get(i);
if (checkIsInCircle(downPointX, downPointY, currentPoint.x, currentPoint.y, outCircleR)) {
//防止反复记下重复点
if (!mSelectData.contains(currentPoint)) {
mSelectData.add(currentPoint);
currentPoint.state = myPoint.STATE_DOWN;
}
}
}
invalidate();
break;
case MotionEvent.ACTION_UP:
isPressFlag = false;
if (mSelectData != null && mSelectData.size() != 0) {
//抬起的时候，密码回调
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < mSelectData.size(); i++) {
stringBuilder.append(mSelectData.get(i).i);
}
// System.out.println("stringBuilder.toString() ->" + stringBuilder.toString());
mOnTouchResult.result(stringBuilder.toString());
}
//清除状态
postDelayed(new Runnable() {
@Override
public void run() {
clearState();
invalidate();
}
},1000);
break;
}
return true;
}
private void clearState() {
isWrongFlag = false;
mSelectData.clear();
for (int i = 0; i < mPointData.size(); i++) {
mPointData.get(i).state = myPoint.STATE_NORMAL;
}
}
//检查是否在圈内
private boolean checkIsInCircle(float downPointX, float downPointY, float centerX, float centerY, float R) {
return Math.sqrt(Math.pow(downPointX - centerX, 2) + Math.pow(downPointY - centerY, 2)) < R;
}
//初始化画笔
private Paint initPaint(int color) {
Paint paint = new Paint();
paint.setDither(true);
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
paint.setColor(color);
paint.setStrokeWidth(5);
return paint;
}
//画圈
private void drawCircle(Canvas canvas) {
System.out.println("drawCircle mSelectData ->" + mSelectData);
System.out.println("drawCircle mPointData ->" + mPointData);
for (int i = 0; i < mPointData.size(); i++) {
if (mPointData.get(i).state == myPoint.STATE_NORMAL) {
canvas.drawCircle(mPointData.get(i).x, mPointData.get(i).y, outCircleR, normalPaint);
canvas.drawCircle(mPointData.get(i).x, mPointData.get(i).y, inCircleR, normalPaint);
} else if (mPointData.get(i).state == myPoint.STATE_DOWN) {
canvas.drawCircle(mPointData.get(i).x, mPointData.get(i).y, outCircleR, downPaint);
canvas.drawCircle(mPointData.get(i).x, mPointData.get(i).y, inCircleR, downPaint);
}else if (mPointData.get(i).state == myPoint.STATE_ERROR) {
canvas.drawCircle(mPointData.get(i).x, mPointData.get(i).y, outCircleR, errorPaint);
canvas.drawCircle(mPointData.get(i).x, mPointData.get(i).y, inCircleR, errorPaint);
}
}
}
//初始化九个单元格
private void initCell() {
mPointData = new ArrayList<>();
//获取布局宽高
int width = getWidth();
int height = getHeight();
//第一个点的位置
float possionX = 0;
float possionY = 0;
//横竖屏兼容,计算第一个点的坐标
if (width < height) {
possionX = width * 1.0f / 6;
possionY = (height - width) 1.0f / 2 + width 1.0f / 6;
height = width;
} else {
possionX = (width - height) 1.0f / 2 + height 1.0f / 6;
possionY = height * 1.0f / 6;
width = height;
}
最后
说一千道一万，不如自己去行动。要想在移动互联网的下半场是自己占有一席之地，那就得从现在开始，从今天开始，马上严格要求自己，既重视业务实现能力，也重视基础和原理。基础夯实好了，高楼才能够平地而起，稳如泰山。
最后为了帮助大家深刻理解Android相关知识点的原理以及面试相关知识，这里放上相关的我搜集整理的24套腾讯、字节跳动、阿里、百度2020-2021面试真题解析，我把技术点整理成了视频和PDF（实际上比预期多花了不少精力），包**知识脉络 +
诸多细节**。
还有?高级架构技术进阶脑图、Android开发面试专题资料?帮助大家学习提升进阶，也节省大家在网上搜索资料的时间来学习，也可以分享给身边好友一起学习。
网上学习 Android的资料一大堆，但如果学到的知识不成体系，遇到问题时只是浅尝辄止，不再深入研究，那么很难做到真正的技术提升。希望这份系统化的技术体系对大家有一个方向参考。
