Android实现九宫格解锁的实例代码

 private ArrayList mListCircle;//外圆的圆心

 for (int i = 0; i 

void drawAll_Cicle(Canvas canvas) {
    for (int i = 0; i 

ArrayList mListRectFs;
for (int i = 0; i 

/**
   * 点和圆形碰撞检测
   *
   * @param x1   手指接触点
   * @param y1   手指接触点
   * @param x2   外圆
   * @param y2   外圆
   * @param radius 半径
   * @return
   */
  private boolean isCollision(float x1, float y1, float x2, float y2, float radius) {
    if (Math.sqrt(Math.pow(x1 - x2, 2) + Math.pow(y1 - y2, 2)) <= radius) {
      // 如果点和圆心距离小于或等于半径则认为发生碰撞
      return true;
    }
    return false;
  }


/**
   * 判断触摸点在哪个item上
   *
   * @param x
   * @param y
   * @return
   */
  private int touchIndex(float x, float y) {
    for (int i = 0; i 

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.util.Log;
import android.view.HapticFeedbackConstants;
import android.view.MotionEvent;
import android.view.View;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;

/**
 * Created by ld on 2017/7/25.
 */

public class NineGridLockView extends View {
  private Context context;
  int index_point = 0;
  private float mDensity;
  private int mCount = 3;
  private ArrayList mListRectFs;//圆的外形矩形
  private ArrayList mListCircle;//外圆的圆心
  private LinkedHashSet mSetPoints;//记录需要连线的外圆圆心点在mListCircle中的索引值，LinkedHashSet线性不可重复 集合，FIFO
  private Paint mPaint, miniPaint;//画笔
  private float mRadius;//外圆半径
  private float mMinRadius;//内圆半径
  private float mStrokeWidth = 10; //绘制时的画笔宽度
  private Point mMovePoint; //记录手指移动时的点

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

  public NineGridLockView(Context context, AttributeSet attrs) {
    super(context, attrs);
    this.cOntext= context;
    mDensity = getContext().getResources().getDisplayMetrics().density;
    mListRectFs = new ArrayList<>();
    mListCircle = new ArrayList<>();
    mPaint = new Paint();
    mPaint.setStrokeWidth(5);
    mPaint.setStyle(Paint.Style.STROKE);
    mPaint.setAntiAlias(true);
    mPaint.setColor(Color.BLUE);

    miniPaint = new Paint();
    miniPaint.setColor(Color.BLACK);
    miniPaint.setAntiAlias(true);
    miniPaint.setStyle(Paint.Style.STROKE);
    miniPaint.setStrokeWidth(5);
    mMinRadius = dp(5);
    mSetPoints = new LinkedHashSet<>();
  }

  @Override
  protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    drawAll_Cicle(canvas);
    draw_line(canvas);
  }

  private int dp(int dp) {
    return (int) (dp * mDensity + 0.5f);
  }

  //绘制 连接线
  void draw_line(Canvas canvas) {
    Point p1 = null;
    Point p2 = null;
    //从结合中获取 move过的点
    for (int index : mSetPoints) {
      //当第一个点为null的时候 给第一个点赋值
      if (p1 == null) {
        p1 = mListCircle.get(index);
        //然后 给第二个点赋值 两点一条线
      } else if (p2 == null) {
        p2 = mListCircle.get(index);
        canvas.drawLine(p1.x, p1.y, p2.x, p2.y, mPaint);
        //p1 挪到p2
        p1 = p2;
        //接下来就是第三个点了 乃至更多点
      } else {
        //p2重新赋值 两点一条线
        p2 = mListCircle.get(index);
        canvas.drawLine(p1.x, p1.y, p2.x, p2.y, mPaint);
        //p1 挪到p2
        p1 = p2;
      }

    }

    //绘制实时连线
    if (mMovePoint != null && p1 != null) {
      canvas.drawLine(p1.x, p1.y, mMovePoint.x, mMovePoint.y, mPaint);
    }
  }

  //绘制 外圆 内圆
  void drawAll_Cicle(Canvas canvas) {
    for (int i = 0; i