先看看效果图：

源码：

package com.zihao.radar; import android.app.Activity; import android.os.Bundle; import android.view.Window; import android.view.WindowManager; import com.zihao.radar.view.RadarView; public class MainActivity extends Activity { private RadarView mRadarView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); // 取消状态栏 getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN); setContentView(R.layout.activity_main); mRadarView = (RadarView) findViewById(R.id.radar_view); mRadarView.setSearching(true); mRadarView.addPoint(); mRadarView.addPoint(); } } package com.zihao.radar.view; import java.util.ArrayList; import java.util.List; import java.util.Random; import android.annotation.SuppressLint; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Paint.Style; import android.util.AttributeSet; import android.view.View; import com.zihao.radar.R; /** * @ClassName：RadarView * @Description：TODO<雷达扫描视图> * @author：zihao * @date：2015年11月11日 上午12:26:11 * @version：v1.1 */ @SuppressLint("DrawAllocation") public class RadarView extends View { private Context mContext; private boolean isSearching = false;// 标识是否处于扫描状态,默认为不在扫描状态 private Paint mPaint;// 画笔 private Bitmap mScanBmp;// 执行扫描运动的图片 private int mOffsetArgs = 0;// 扫描运动偏移量参数 private Bitmap mDefaultPointBmp;// 标识设备的圆点-默认 private Bitmap mLightPointBmp;// 标识设备的圆点-高亮 private int mPointCount = 0;// 圆点总数 private List<String> mPointArray = new ArrayList<String>();// 存放偏移量的map private Random mRandom = new Random(); private int mWidth, mHeight;// 宽高 int mOutWidth;// 外圆宽度(w/4/5*2=w/10) int mCx, mCy;// x、y轴中心点 int mOutsideRadius, mInsideRadius;// 外、内圆半径 public RadarView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); // TODO Auto-generated constructor stub init(context); } public RadarView(Context context, AttributeSet attrs) { super(context, attrs); // TODO Auto-generated constructor stub init(context); } public RadarView(Context context) { super(context); // TODO Auto-generated constructor stub init(context); } /** * TODO<提前初始化好需要使用的对象,避免在绘制过程中多次初始化> * * @return void */ private void init(Context context) { mPaint = new Paint(); this.mContext = context; this.mDefaultPointBmp = Bitmap.createBitmap(BitmapFactory .decodeResource(mContext.getResources(), R.drawable.radar_default_point_ico)); this.mLightPointBmp = Bitmap.createBitmap(BitmapFactory.decodeResource( mContext.getResources(), R.drawable.radar_light_point_ico)); } /** * 测量视图及其内容,以确定所测量的宽度和高度(测量获取控件尺寸). */ @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { // TODO Auto-generated method stub super.onMeasure(widthMeasureSpec, heightMeasureSpec); // 获取控件区域宽高 if (mWidth == 0 || mHeight == 0) { final int minimumWidth = getSuggestedMinimumWidth(); final int minimumHeight = getSuggestedMinimumHeight(); mWidth = resolveMeasured(widthMeasureSpec, minimumWidth); mHeight = resolveMeasured(heightMeasureSpec, minimumHeight); mScanBmp = Bitmap.createScaledBitmap(BitmapFactory.decodeResource( mContext.getResources(), R.drawable.radar_scan_img), mWidth - mOutWidth, mWidth - mOutWidth, false); // 获取x/y轴中心点 mCx = mWidth / 2; mCy = mHeight / 2; // 获取外圆宽度 mOutWidth = mWidth / 10; // 计算内、外半径 mOutsideRadius = mWidth / 2;// 外圆的半径 mInsideRadius = (mWidth - mOutWidth) / 4 / 2;// 内圆的半径,除最外层,其它圆的半径=层数*insideRadius } } /** * 绘制视图--从外部向内部绘制 */ @Override protected void onDraw(Canvas canvas) { // TODO Auto-generated method stub super.onDraw(canvas); // 开始绘制最外层的圆 mPaint.setAntiAlias(true);// 设置抗锯齿 mPaint.setStyle(Style.FILL);// 设置填充样式 mPaint.setColor(0xffB8DCFC);// 设置画笔颜色 // 1.开始绘制圆形 canvas.drawCircle(mCx, mCy, mOutsideRadius, mPaint); // 开始绘制内4圆 mPaint.setColor(0xff3278B4); canvas.drawCircle(mCx, mCy, mInsideRadius * 4, mPaint); // 开始绘制内3圆 mPaint.setStyle(Style.STROKE); mPaint.setColor(0xff31C9F2); canvas.drawCircle(mCx, mCy, mInsideRadius * 3, mPaint); // 开始绘制内2圆 canvas.drawCircle(mCx, mCy, mInsideRadius * 2, mPaint); // 开始绘制内1圆 canvas.drawCircle(mCx, mCy, mInsideRadius * 1, mPaint); // 2.开始绘制对角线 canvas.drawLine(mOutWidth / 2, mCy, mWidth - mOutWidth / 2, mCy, mPaint);// 绘制0°~180°对角线 canvas.drawLine(mCx, mHeight - mOutWidth / 2, mCx, mOutWidth / 2, mPaint);// 绘制90°~270°对角线 // 根据角度绘制对角线 int startX, startY, endX, endY; double radian; // 绘制45°~225°对角线 // 计算开始位置x/y坐标点 radian = Math.toRadians((double) 45);// 将角度转换为弧度 startX = (int) (mCx + mInsideRadius * 4 * Math.cos(radian));// 通过圆心坐标、半径和当前角度计算当前圆周的某点横坐标 startY = (int) (mCy + mInsideRadius * 4 * Math.sin(radian));// 通过圆心坐标、半径和当前角度计算当前圆周的某点纵坐标 // 计算结束位置x/y坐标点 radian = Math.toRadians((double) 45 + 180); endX = (int) (mCx + mInsideRadius * 4 * Math.cos(radian)); endY = (int) (mCy + mInsideRadius * 4 * Math.sin(radian)); canvas.drawLine(startX, startY, endX, endY, mPaint); // 绘制135°~315°对角线 // 计算开始位置x/y坐标点 radian = Math.toRadians((double) 135); startX = (int) (mCx + mInsideRadius * 4 * Math.cos(radian)); startY = (int) (mCy + mInsideRadius * 4 * Math.sin(radian)); // 计算结束位置x/y坐标点 radian = Math.toRadians((double) 135 + 180); endX = (int) (mCx + mInsideRadius * 4 * Math.cos(radian)); endY = (int) (mCy + mInsideRadius * 4 * Math.sin(radian)); canvas.drawLine(startX, startY, endX, endY, mPaint); // 3.绘制扫描扇形图 canvas.save();// 用来保存Canvas的状态.save之后，可以调用Canvas的平移、放缩、旋转、错切、裁剪等操作. if (isSearching) {// 判断是否处于扫描 canvas.rotate(mOffsetArgs, mCx, mCy);// 绘制旋转角度,参数一：角度;参数二：x中心;参数三：y中心. canvas.drawBitmap(mScanBmp, mCx - mScanBmp.getWidth() / 2, mCy - mScanBmp.getHeight() / 2, null);// 绘制Bitmap扫描图片效果 mOffsetArgs += 3; } else { canvas.drawBitmap(mScanBmp, mCx - mScanBmp.getWidth() / 2, mCy - mScanBmp.getHeight() / 2, null); } // 4.开始绘制动态点 canvas.restore();// 用来恢复Canvas之前保存的状态.防止save后对Canvas执行的操作对后续的绘制有影响. if (mPointCount > 0) {// 当圆点总数>0时,进入下一层判断 if (mPointCount > mPointArray.size()) {// 当圆点总数大于存储坐标点数目时,说明有增加,需要重新生成随机坐标点 int mx = mInsideRadius + mRandom.nextInt(mInsideRadius * 6); int my = mInsideRadius + mRandom.nextInt(mInsideRadius * 6); mPointArray.add(mx + "/" + my); } // 开始绘制坐标点 for (int i = 0; i < mPointArray.size(); i++) { String[] result = mPointArray.get(i).split("/"); // 开始绘制动态点 if (i < mPointArray.size() - 1) canvas.drawBitmap(mDefaultPointBmp, Integer.parseInt(result[0]), Integer.parseInt(result[1]), null); else canvas.drawBitmap(mLightPointBmp, Integer.parseInt(result[0]), Integer.parseInt(result[1]), null); } } if (isSearching) this.invalidate(); } /** * TODO<设置扫描状态> * * @return void */ public void setSearching(boolean status) { this.isSearching = status; this.invalidate(); } /** * TODO<新增动态点> * * @return void */ public void addPoint() { mPointCount++; this.invalidate(); } /** * TODO<解析获取控件宽高> * * @return int */ private int resolveMeasured(int measureSpec, int desired) { int result = 0; int specSize = MeasureSpec.getSize(measureSpec); switch (MeasureSpec.getMode(measureSpec)) { case MeasureSpec.UNSPECIFIED: result = desired; break; case MeasureSpec.AT_MOST: result = Math.min(specSize, desired); break; case MeasureSpec.EXACTLY: default: result = specSize; } return result; } } <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/bgp" tools:context="com.zihao.radar.MainActivity" > <com.zihao.radar.view.RadarView android:id="@+id/radar_view" android:layout_width="600px" android:layout_height="600px" android:layout_centerInParent="true" /> </RelativeLayout>

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