[Android实例] android多点触摸demo

MultiTouchActivity

package com.zhaokai.multitouch;import android.app.Activity;import android.os.Bundle;import android.view.Window;import android.view.WindowManager;public class MultiTouchActivity extends Activity {    /** Called when the activity is first created. */ /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);                //隐藏标题栏                requestWindowFeature(Window.FEATURE_NO_TITLE);                //设置成全屏               getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);                //设置为上面的MTView                setContentView(new MySurfaceView(this));      }}

SurfaceView类：

package com.zhaokai.multitouch;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.view.MotionEvent;import android.view.SurfaceHolder;import android.view.SurfaceHolder.Callback;import android.view.SurfaceView;public class MySurfaceView extends SurfaceView implements Callback{private static final int MAX_TOUCHPOINTS = 10;private static final String START_TEXT = "请随便触摸屏幕进行测试";      private Paint textPaint = new Paint();      private Paint touchPaints[] = new Paint[MAX_TOUCHPOINTS];      private int colors[] = new int[MAX_TOUCHPOINTS];         private int width, height;      private float scale = 1.0f;public MySurfaceView(Context context) {  super(context);  SurfaceHolder holder = getHolder();            holder.addCallback(this);            setFocusable(true); // 确保我们的View能获得输入焦点            setFocusableInTouchMode(true); // 确保能接收到触屏事件            init();  }public void init(){  // 初始化10个不同颜色的画笔            textPaint.setColor(Color.WHITE);    colors[0] = Color.BLUE;    colors[1] = Color.RED;  colors[2] = Color.GREEN;  colors[3] = Color.YELLOW;  colors[4] = Color.CYAN;  colors[5] = Color.MAGENTA;  colors[6] = Color.DKGRAY;  colors[7] = Color.WHITE;  colors[8] = Color.LTGRAY;  colors[9] = Color.GRAY;  for(int i=0;i<MAX_TOUCHPOINTS;i++){   touchPaints[i]=new Paint();   touchPaints[i].setColor(colors[i]);  }}@Overridepublic boolean onTouchEvent(MotionEvent event) {  int pointerCount=event.getPointerCount();  if(pointerCount>MAX_TOUCHPOINTS){   pointerCount=MAX_TOUCHPOINTS;  }  Canvas c=getHolder().lockCanvas();  if(c!=null){   c.drawColor(Color.BLACK);   if(event.getAction()==MotionEvent.ACTION_UP){    // 当手离开屏幕时，清屏    c.drawColor(Color.BLACK);   }else{     // 先在屏幕上画一个十字，然后画一个圆    for(int i=0;i<pointerCount;i++){     //获取一个触点的坐标，然后开始绘制     int id=event.getPointerId(i);     int x=(int)event.getX(i);     int y=(int)event.getY(i);     drawCrosshairsAndText(x, y, touchPaints[id], i, id, c);    }    for(int i=0;i<pointerCount;i++){     int id=event.getPointerId(i);     int x=(int)event.getX(i);     int y=(int)event.getY(i);     drawCircle(x, y, touchPaints[id],c);    }   }   getHolder().unlockCanvasAndPost(c);  }  return true;}private void drawCrosshairsAndText(int x, int y, Paint paint, int ptr,int id, Canvas c) {  c.drawLine(0, y, width, y, paint);            c.drawLine(x, 0, x, height, paint);            int textY = (int) ((15 + 20 * ptr) * scale);            c.drawText("x" + ptr + "=" + x, 10 * scale, textY, textPaint);            c.drawText("y" + ptr + "=" + y, 70 * scale, textY, textPaint);            c.drawText("id" + ptr + "=" + id, width - 55 * scale, textY, textPaint);   }  private void drawCircle(int x, int y, Paint paint, Canvas c) {  c.drawCircle(x, y, 40 * scale, paint);      }  @Overridepublic void surfaceChanged(SurfaceHolder holder, int format, int width,   int height) {   this.width = width;             this.height = height;             if (width > height){                  this.scale = width / 480f;             } else {   this.scale = height / 480f;             }             textPaint.setTextSize(14 * scale);             Canvas c = getHolder().lockCanvas();             if (c != null) {              // 背景黑色                  c.drawColor(Color.BLACK);                  float tWidth = textPaint.measureText(START_TEXT);                  c.drawText(START_TEXT, width / 2 - tWidth / 2, height / 2,textPaint);                  getHolder().unlockCanvasAndPost(c);            }  }@Overridepublic void surfaceCreated(SurfaceHolder holder) {  // TODO Auto-generated method stub  }@Overridepublic void surfaceDestroyed(SurfaceHolder holder) {  // TODO Auto-generated method stub  } }

更多相关文章

随机推荐