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,默認為不在掃描狀態   private Paint mPaint;// 畫筆   private Bitmap mScanBmp;// 執行掃描運動的圖片   private int mOffsetArgs = 0;// 掃描運動偏移量參數   private Bitmap mDefaultPointBmp;// 標識設備的圓點-默認   private Bitmap mLightPointBmp;// 標識設備的圓點-高亮   private int mPointCount = 0;// 圓點總數   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);      // 獲取控件區域寬高     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);        // 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、外半徑       mOutsideRadius = mWidth / 2;// 外圓的半徑       mInsideRadius = (mWidth - mOutWidth) / 4 / 2;// 內圓的半徑,除最外層,其它圓的半徑=層數*insideRadius     }   }    /**    * 繪制視圖--從外部向內部繪制    */   @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);// 設置抗鋸齒     mPaint.setStyle(Style.FILL);// 設置填充樣式     mPaint.setColor(0xffB8DCFC);// 設置畫筆顏色     // 1.開始繪制圓形     canvas.drawCircle(mCx, mCy, mOutsideRadius, mPaint);      // 開始繪制內4圓     mPaint.setColor(0xff3278B4);     canvas.drawCircle(mCx, mCy, mInsideRadius * 4, mPaint);      // 開始繪制內3圓     mPaint.setStyle(Style.STROKE);     mPaint.setColor(0xff31C9F2);     canvas.drawCircle(mCx, mCy, mInsideRadius * 3, mPaint);      // 開始繪制內2圓     canvas.drawCircle(mCx, mCy, mInsideRadius * 2, mPaint);      // 開始繪制內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.save之后，可以調用Canvas的平移、放縮、旋轉、錯切、裁剪等操作.      if (isSearching) {// 判斷是否處于掃描       canvas.rotate(mOffsetArgs, mCx, mCy);// 繪制旋轉角度,參數一：角度;參數二：x中心;參數三：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.開始繪制動態點     canvas.restore();// 用來恢復Canvas之前保存的狀態.防止save后對Canvas執行的操作對后續的繪制有影響.      if (mPointCount > 0) {// 當圓點總數>0時,進入下一層判斷        if (mPointCount > mPointArray.size()) {// 當圓點總數大于存儲坐標點數目時,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<設置掃描狀態>    *    * @return void    */   public void setSearching(boolean status) {     this.isSearching = status;     this.invalidate();   }    /**    * TODO<新增動態點>    *    * @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>