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); 
    // 取消狀態(tài)欄 
    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<雷達掃描視圖> 
 * @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;// 標識是否處于掃描狀態(tài),默認為不在掃描狀態(tài) 
  private Paint mPaint;// 畫筆 
  private Bitmap mScanBmp;// 執(zhí)行掃描運動的圖片 
  private int mOffsetArgs = 0;// 掃描運動偏移量參數(shù) 
  private Bitmap mDefaultPointBmp;// 標識設(shè)備的圓點-默認 
  private Bitmap mLightPointBmp;// 標識設(shè)備的圓點-高亮 
  private int mPointCount = 0;// 圓點總數(shù) 
  private List<String> mPointArray = new ArrayList<String>();// 存放偏移量的map 
  private Random mRandom = new Random(); 
  private int mWidth, mHeight;// 寬高 
  int mOutWidth;// 外圓寬度(w/4/5*2=w/10) 
  int mCx, mCy;// x、y軸中心點 
  int mOutsideRadius, mInsideRadius;// 外、內(nèi)圓半徑 
 
  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對象,避免在繪制過程中多次初始化> 
   * 
   * @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)); 
  } 
 
  /** 
   * 測量視圖及其內(nèi)容,以確定所測量的寬度和高度(測量獲取控件尺寸). 
   */ 
  @Override 
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 
    // TODO Auto-generated method stub 
    super.onMeasure(widthMeasureSpec, heightMeasureSpec); 
 
    // 獲取控件區(qū)域?qū)捀?
    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); 
 
      // 獲取x/y軸中心點 
      mCx = mWidth / 2; 
      mCy = mHeight / 2; 
 
      // 獲取外圓寬度 
      mOutWidth = mWidth / 10; 
 
      // 計算內(nèi)、外半徑 
      mOutsideRadius = mWidth / 2;// 外圓的半徑 
      mInsideRadius = (mWidth - mOutWidth) / 4 / 2;// 內(nèi)圓的半徑,除最外層,其它圓的半徑=層數(shù)*insideRadius 
    } 
  } 
 
  /** 
   * 繪制視圖--從外部向內(nèi)部繪制 
   */ 
  @Override 
  protected void onDraw(Canvas canvas) { 
    // TODO Auto-generated method stub 
    super.onDraw(canvas); 
    // 開始繪制最外層的圓 
    mPaint.setAntiAlias(true);// 設(shè)置抗鋸齒 
    mPaint.setStyle(Style.FILL);// 設(shè)置填充樣式 
    mPaint.setColor(0xffB8DCFC);// 設(shè)置畫筆顏色 
    // 1.開始繪制圓形 
    canvas.drawCircle(mCx, mCy, mOutsideRadius, mPaint); 
 
    // 開始繪制內(nèi)4圓 
    mPaint.setColor(0xff3278B4); 
    canvas.drawCircle(mCx, mCy, mInsideRadius * 4, mPaint); 
 
    // 開始繪制內(nèi)3圓 
    mPaint.setStyle(Style.STROKE); 
    mPaint.setColor(0xff31C9F2); 
    canvas.drawCircle(mCx, mCy, mInsideRadius * 3, mPaint); 
 
    // 開始繪制內(nèi)2圓 
    canvas.drawCircle(mCx, mCy, mInsideRadius * 2, mPaint); 
 
    // 開始繪制內(nèi)1圓 
    canvas.drawCircle(mCx, mCy, mInsideRadius * 1, mPaint); 
 
    // 2.開始繪制對角線 
    canvas.drawLine(mOutWidth / 2, mCy, mWidth - mOutWidth / 2, mCy, mPaint);// 繪制0°~180°對角線 
    canvas.drawLine(mCx, mHeight - mOutWidth / 2, mCx, mOutWidth / 2, 
        mPaint);// 繪制90°~270°對角線 
 
    // 根據(jù)角度繪制對角線 
    int startX, startY, endX, endY; 
    double radian; 
 
    // 繪制45°~225°對角線 
    // 計算開始位置x/y坐標點 
    radian = Math.toRadians((double) 45);// 將角度轉(zhuǎn)換為弧度 
    startX = (int) (mCx + mInsideRadius * 4 * Math.cos(radian));// 通過圓心坐標、半徑和當前角度計算當前圓周的某點橫坐標 
    startY = (int) (mCy + mInsideRadius * 4 * Math.sin(radian));// 通過圓心坐標、半徑和當前角度計算當前圓周的某點縱坐標 
    // 計算結(jié)束位置x/y坐標點 
    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); 
 
    // 繪制135°~315°對角線 
    // 計算開始位置x/y坐標點 
    radian = Math.toRadians((double) 135); 
    startX = (int) (mCx + mInsideRadius * 4 * Math.cos(radian)); 
    startY = (int) (mCy + mInsideRadius * 4 * Math.sin(radian)); 
    // 計算結(jié)束位置x/y坐標點 
    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.繪制掃描扇形圖 
    canvas.save();// 用來保存Canvas的狀態(tài).save之后，可以調(diào)用Canvas的平移、放縮、旋轉(zhuǎn)、錯切、裁剪等操作. 
 
    if (isSearching) {// 判斷是否處于掃描 
      canvas.rotate(mOffsetArgs, mCx, mCy);// 繪制旋轉(zhuǎn)角度,參數(shù)一：角度;參數(shù)二：x中心;參數(shù)三：y中心. 
      canvas.drawBitmap(mScanBmp, mCx - mScanBmp.getWidth() / 2, mCy 
          - mScanBmp.getHeight() / 2, null);// 繪制Bitmap掃描圖片效果 
      mOffsetArgs += 3; 
    } else { 
      canvas.drawBitmap(mScanBmp, mCx - mScanBmp.getWidth() / 2, mCy 
          - mScanBmp.getHeight() / 2, null); 
    } 
 
    // 4.開始繪制動態(tài)點 
    canvas.restore();// 用來恢復(fù)Canvas之前保存的狀態(tài).防止save后對Canvas執(zhí)行的操作對后續(xù)的繪制有影響. 
 
    if (mPointCount > 0) {// 當圓點總數(shù)>0時,進入下一層判斷 
 
      if (mPointCount > mPointArray.size()) {// 當圓點總數(shù)大于存儲坐標點數(shù)目時,說明有增加,需要重新生成隨機坐標點 
        int mx = mInsideRadius + mRandom.nextInt(mInsideRadius * 6); 
        int my = mInsideRadius + mRandom.nextInt(mInsideRadius * 6); 
        mPointArray.add(mx + "/" + my); 
      } 
 
      // 開始繪制坐標點 
      for (int i = 0; i < mPointArray.size(); i++) { 
        String[] result = mPointArray.get(i).split("/"); 
 
        // 開始繪制動態(tài)點 
        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<設(shè)置掃描狀態(tài)> 
   * 
   * @return void 
   */ 
  public void setSearching(boolean status) { 
    this.isSearching = status; 
    this.invalidate(); 
  } 
 
  /** 
   * TODO<新增動態(tài)點> 
   * 
   * @return void 
   */ 
  public void addPoint() { 
    mPointCount++; 
    this.invalidate(); 
  } 
 
  /** 
   * TODO<解析獲取控件寬高> 
   * 
   * @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>