Android SurfaceView实现静态于动态画图效果


本文是基于Android的SurfaceView的动态画图效果，实现静态和动态下的正弦波画图，可作为自己做图的简单参考，废话不多说，先上图，

静态效果：


动态效果：


比较简单，代码注释的也比较详细，易懂，我就直接上代码了吧：

1.main.xml

  1. <?xml version="1.0" encoding="utf-8"?>  
  2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
  3.     android:layout_width="fill_parent"  
  4.     android:layout_height="fill_parent"  
  5.     android:orientation="vertical" >  
  6. <SurfaceView   
  7.     android:layout_width="fill_parent"  
  8.     android:layout_height="600px"  
  9.     android:id="@+id/surfaceview_draw"/>  
  10. <RelativeLayout android:layout_width="fill_parent"  
  11.     android:layout_height="wrap_content">  
  12. <Button android:layout_below="@id/surfaceview_draw"  
  13.     android:layout_marginLeft="7dip"  
  14.     android:id="@+id/simpledraw_btn"  
  15.     android:text="简单绘图"  
  16.     android:layout_width="wrap_content"  
  17.     android:layout_height="wrap_content"  
  18.     android:textSize="20dip"/>  
  19.   
  20. <Button  
  21.     android:id="@+id/timerdraw_btn"  
  22.     android:layout_width="wrap_content"  
  23.     android:layout_height="wrap_content"  
  24.     android:layout_toRightOf="@id/simpledraw_btn"  
  25.     android:text="定时绘图"   
  26.     android:textSize="20dip"/>  
  27. <Button   
  28.     android:id="@+id/cleardraw_btn"  
  29.     android:layout_width="wrap_content"  
  30.     android:layout_height="wrap_content"  
  31.     android:layout_toRightOf="@id/timerdraw_btn"  
  32.     android:text="清除图像"  
  33.     android:textSize="20dip"/>  
  34. </RelativeLayout>  
  35. </LinearLayout>  
2.SurfaceViewDrawActivity.java
  1. package com.huangcheng.draw;  
  2.   
  3. import java.util.Timer;  
  4. import java.util.TimerTask;  
  5.   
  6. import android.app.Activity;  
  7. import android.graphics.Canvas;  
  8. import android.graphics.Color;  
  9. import android.graphics.Paint;  
  10. import android.graphics.Rect;  
  11. import android.os.Bundle;  
  12. import android.util.Log;  
  13. import android.view.SurfaceHolder;  
  14. import android.view.SurfaceView;  
  15. import android.view.View;  
  16. import android.view.View.OnClickListener;  
  17. import android.widget.Button;  
  18.   
  19. public class SurfaceViewDrawActivity extends Activity {  
  20.     /** Called when the activity is first created. */  
  21.     private SurfaceView surface_draw;  
  22.     private SurfaceHolder surfaceholder;  
  23.   
  24.     private Button simpledraw_btn;  
  25.     private Button timerdraw_btn;  
  26.     private Button cleardraw_btn;  
  27.   
  28.     private Timer timer;  
  29.     private TimerTask timertask;  
  30.   
  31.     private int[] Y;// 保存图像Y轴上的点   
  32.     private int centerY, oldX, oldY, currentX;// 保存水平中心线位置,上一个(x,y)点，当先绘制到的x   
  33.   
  34.     private volatile int signal=0;  
  35.     @Override  
  36.     public void onCreate(Bundle savedInstanceState) {  
  37.         super.onCreate(savedInstanceState);  
  38.         setContentView(R.layout.main);  
  39.         surface_draw = (SurfaceView) findViewById(R.id.surfaceview_draw);  
  40.         surfaceholder = surface_draw.getHolder();  
  41.   
  42.         simpledraw_btn = (Button) findViewById(R.id.simpledraw_btn);  
  43.         timerdraw_btn = (Button) findViewById(R.id.timerdraw_btn);  
  44.         cleardraw_btn = (Button) findViewById(R.id.cleardraw_btn);  
  45.         cleardraw_btn.setEnabled(false);  
  46.   
  47.         centerY = 300;  
  48.         Y = new int[getWindowManager().getDefaultDisplay().getWidth()];  
  49.         for (int i = 1; i < Y.length + 1; i++) {  
  50.             Y[i - 1] = centerY + (int) (100 * Math.sin(i * 2 * Math.PI / 180));  
  51.             // System.out.println("sin:"+100*Math.sin(i*2*Math.PI/180));   
  52.         }  
  53.         simpledraw_btn.setOnClickListener(new OnClickListener() {  
  54.   
  55.             @Override  
  56.             public void onClick(View arg0) {  
  57.                 // TODO Auto-generated method stub   
  58.                 simpledraw();// 静态绘制正弦图   
  59.                 signal=1;  
  60.                 simpledraw_btn.setEnabled(false);  
  61.                 timerdraw_btn.setEnabled(false);  
  62.                 cleardraw_btn.setEnabled(true);  
  63.             }  
  64.         });  
  65.         timerdraw_btn.setOnClickListener(new OnClickListener() {  
  66.   
  67.             @Override  
  68.             public void onClick(View arg0) {  
  69.                 // TODO Auto-generated method stub   
  70.                 oldX=0;  
  71.                 oldY=centerY;  
  72.                 currentX=0;  
  73.                 timer=new Timer();  
  74.                 timertask=new TimerTask() {  
  75.                       
  76.                     @Override  
  77.                     public void run() {  
  78.                         // TODO Auto-generated method stub   
  79.                         currentX++;  
  80.                         complexdraw(currentX);  
  81.                         if(currentX==Y.length-1){  
  82.                             ClearDraw();  
  83.                             currentX = 0;  
  84.                             oldX=0;  
  85.                             oldY=centerY;  
  86.                         }  
  87.                     }  
  88.                 };  
  89.                 timer.schedule(timertask, 0, 5);// 动态绘制正弦图   
  90.                 signal=2;  
  91.                 simpledraw_btn.setEnabled(false);  
  92.                 timerdraw_btn.setEnabled(false);  
  93.                 cleardraw_btn.setEnabled(true);  
  94.             }  
  95.         });  
  96.         cleardraw_btn.setOnClickListener(new OnClickListener() {  
  97.               
  98.             @Override  
  99.             public void onClick(View arg0) {  
  100.                 // TODO Auto-generated method stub   
  101.                 if(signal==1){  
  102.                     ClearDraw();  
  103.                     simpledraw_btn.setEnabled(true);  
  104.                     timerdraw_btn.setEnabled(true);  
  105.                 }  
  106.                 if(signal==2){  
  107.                     timertask.cancel();  
  108.                     timer.cancel();  
  109.                     ClearDraw();  
  110.                     simpledraw_btn.setEnabled(true);  
  111.                     timerdraw_btn.setEnabled(true);  
  112.                 }  
  113.             }  
  114.         });  
  115.     }  
  116.     // 简单画图   
  117.     void simpledraw() {  
  118.         oldX = 0;  
  119.         oldY = centerY;  
  120.         Canvas canvas = surfaceholder  
  121.                 .lockCanvas(new Rect(oldX, 0, oldX + Y.length,  
  122.                         getWindowManager().getDefaultDisplay().getHeight()));// 关键:获取画布   
  123.         Log.i("Canvas:X:",  
  124.                 String.valueOf(oldX) + "," + String.valueOf(oldX + Y.length));  
  125.   
  126.         Paint mPaint = new Paint();  
  127.         mPaint.setColor(Color.GREEN);// 画笔为绿色   
  128.         mPaint.setStrokeWidth(2);// 设置画笔粗细   
  129.   
  130.         int y;  
  131.   
  132.         for (int i = oldX + 1; i < Y.length; i++) {// 绘画正弦波   
  133.             y = Y[i - 1];  
  134.             canvas.drawLine(oldX, oldY, i, y, mPaint);  
  135.             // System.out.println("oldX:"+oldX+" oldY:"+oldY+",x:"+i+" y:"+y);   
  136.             oldX = i;  
  137.             oldY = y;  
  138.         }  
  139.         surfaceholder.unlockCanvasAndPost(canvas);  
  140.     }  
  141.   
  142.     // 消除画得图   
  143.     void ClearDraw() {  
  144.         Canvas canvas = surfaceholder.lockCanvas(null);  
  145.         canvas.drawColor(Color.BLACK);// 清除画布   
  146.         surfaceholder.unlockCanvasAndPost(canvas);  
  147.     }  
  148.     //动态画图   
  149.     void complexdraw(int current){  
  150.         Canvas canvas = surfaceholder  
  151.                 .lockCanvas(new Rect(oldX, 0, current,  
  152.                         getWindowManager().getDefaultDisplay().getHeight()));// 关键:获取画布   
  153.         Log.i("Canvas:X:",  
  154.                 String.valueOf(oldX) + "," + String.valueOf(oldX + Y.length));  
  155.   
  156.         Paint mPaint = new Paint();  
  157.         mPaint.setColor(Color.GREEN);// 画笔为绿色   
  158.         mPaint.setStrokeWidth(2);// 设置画笔粗细   
  159.           
  160.         int y=Y[current-1];  
  161.         canvas.drawLine(oldX, oldY, current, y, mPaint);  
  162.         // System.out.println("oldX:"+oldX+" oldY:"+oldY+",x:"+i+" y:"+y);   
  163.         oldX = current;  
  164.         oldY = y;  
  165.         surfaceholder.unlockCanvasAndPost(canvas);  
  166.     }  
  167. }  

更多Android相关信息见Android 专题页面 http://www.bkjia.com/topicnews.aspx?tid=11

相关内容