Android实现检测手机多点触摸点数
作者:橙汁丶
这篇文章主要为大家详细介绍了Android实现检测手机多点触摸点数,文中示例代码介绍的非常详细,具有一定的参考价值,感兴趣的小伙伴们可以参考一下
本文实例为大家分享了Android检测手机多点触摸点数的具体代码,供大家参考,具体内容如下
说明:手指每点击一个地方,在那个地方就画一个圆
第一种方式:
效果图:
Java代码:
首先我们要写一个绘圆类
package com.example.myapplication; /** * Created by Administrator on 2017/7/9 0009. */ import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import java.util.Random; /** * 一个圆类 */ public class Circle { public float x; //圆心点的x坐标 public float y; //圆心点的y坐标 public int r=100; //圆的半径 public int pointId; //员的下标 //初始化颜色 int red; int green; int blue; Random random=new Random();//初始化随机数 public Circle(float x,float y,int pointId){ this.x=x; this.y=y; this.pointId=pointId; red=random.nextInt(255); green=random.nextInt(255); blue=random.nextInt(255); } public void drawSelf(Canvas canvas, Paint paint){ paint.setColor(Color.rgb(red,green,blue)); canvas.drawCircle(x,y,r,paint); } }
然后有一个自定义的控件类
package com.example.myapplication; import android.content.Context; import android.graphics.Canvas; import android.graphics.Paint; import android.support.annotation.Nullable; import android.util.AttributeSet; import android.util.Log; import android.view.MotionEvent; import android.view.SurfaceView; import android.view.View; import java.util.ArrayList; import java.util.List; /** * Created by Administrator on 2017/7/9 0009. */ public class MyView extends View { //定义个圆的集合 private List<Circle> circles=new ArrayList<>(); public MyView(Context context) { super(context); } public MyView(Context context, @Nullable AttributeSet attrs) { super(context, attrs); } public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); } public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); Paint paint=new Paint(); for (Circle circle : circles) { circle.drawSelf(canvas,paint); } } @Override public boolean onTouchEvent(MotionEvent event) { //获取手指的行为 int action=event.getAction(); int action_code=action&0xff; //手指的下标index int pointIndex=action>>8; //获取手值的坐标 float x=event.getX(pointIndex); float y=event.getY(pointIndex); //获取手值的名字(ID) int pointId=event.getPointerId(pointIndex); if(action_code>=5){ action_code-=5; } //单点触摸时用action判断 //多点触摸时用action_code判断 switch (action_code){ case MotionEvent.ACTION_DOWN: //按下 //实例化圆 Circle circle=new Circle(x,y,pointId); //将圆添加到集合中 circles.add(circle); break; case MotionEvent.ACTION_UP: //抬起 //找到具体的圆将它从集合中移除即可 circles.remove(get(pointId)); break; case MotionEvent.ACTION_MOVE: //移动 //找到具体的圆,时时修改圆心点坐标即可 for (int i = 0; i <event.getPointerCount(); i++) { int id=event.getPointerId(i);//得打具体圆的id //从新给圆赋值圆心点坐标 get(id).x=event.getX(i); get(id).y=event.getY(i); } break; } //重新调用onDraw 重绘 invalidate(); //子线程中重新绘制 postInvalidate(); return true; } //定义一个方法,通过pointId返回具体的圆 public Circle get(int pointId){ for (Circle circle : circles) { if(circle.pointId==pointId){ return circle; } } return null; } }
使用的话,就在Activity的setContentView(new MTView); 或者在XML文件中以控件的形式
第二种方式:
效果图:
写一个Java类
package com.example.myapplication; 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.SurfaceView; /** * Created by Administrator on 2017/7/9 0009. */ public class MTView extends SurfaceView implements SurfaceHolder.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 MTView(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(); } private 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]); } } /** * 处理触屏事件 */ @Override public boolean onTouchEvent(MotionEvent event) { // 获得屏幕触点数量 int pointerCount = event.getPointerCount(); if (pointerCount > MAX_TOUCHPOINTS) { pointerCount = MAX_TOUCHPOINTS; } // 锁定Canvas,开始进行相应的界面处理 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 } else { // 在每一个触点上绘制一个十字和坐标信息 for (int i = 0; i < pointerCount; i++) { 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); } // 在每一个触点上绘制一个圆 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); } } // 画完后,unlock getHolder().unlockCanvasAndPost(c); } return true; } /** * 画十字及坐标信息 * * @param x * @param y * @param paint * @param ptr * @param id * @param c */ 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); } /** * 画圆 * * @param x * @param y * @param paint * @param c */ private void drawCircle(int x, int y, Paint paint, Canvas c) { c.drawCircle(x, y, 40 * scale, paint); } @Override public void surfaceCreated(SurfaceHolder holder) { } /** * 进入程序时背景画成黑色,然后把START_TEXT写到屏幕 */ @Override public 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) { c.drawColor(Color.BLACK); float tWidth = textPaint.measureText(START_TEXT); c.drawText(START_TEXT, width / 2 - tWidth / 2, height / 2, textPaint); getHolder().unlockCanvasAndPost(c); } } @Override public void surfaceDestroyed(SurfaceHolder holder) { } }
使用的话,就在Activity的setContentView(new MTView);
一个圆逐渐扩大半径
Java 代码
package com.example.myapplication; /** * Created by Administrator on 2017/7/9 0009. */ import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import java.util.Random; /** * 一个圆类 */ public class Circle { public MyView myView; public float x; //圆心点的x坐标 public float y; //圆心点的y坐标 public int r; //圆的半径 public int pointId; //员的下标 //初始化颜色 int red; int green; int blue; Random random=new Random();//初始化随机数 public Circle(float x,float y,int r,int pointId){ this.x=x; this.y=y; this.r=r; this.pointId=pointId; red=random.nextInt(255); green=random.nextInt(255); blue=random.nextInt(255); } public void drawSelf(Canvas canvas, Paint paint){ paint.setColor(Color.rgb(red,green,blue)); paint.setStyle(Paint.Style.STROKE); canvas.drawCircle(x,y,r,paint); } }
自定义控件类
package com.example.myapplication; import android.content.Context; import android.graphics.Canvas; import android.graphics.Paint; import android.support.annotation.Nullable; import android.util.AttributeSet; import android.util.Log; import android.view.MotionEvent; import android.view.SurfaceView; import android.view.View; import java.util.ArrayList; import java.util.List; /** * Created by Administrator on 2017/7/9 0009. */ public class MyView extends View { //定义个圆的集合 private List<Circle> circles=new ArrayList<>(); //定义个一个全局变量 int pointId; float X; float Y; int r=10; public MyView(Context context) { super(context); } public MyView(Context context, @Nullable AttributeSet attrs) { super(context, attrs); } public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); } public MyView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); Paint paint=new Paint(); for (Circle circle : circles) { circle.drawSelf(canvas,paint); } } @Override public boolean onTouchEvent(MotionEvent event) { //获取手指的行为 int action=event.getAction(); int action_code=action&0xff; //手指的下标index int pointIndex=action>>8; //获取手值的坐标 float x=event.getX(pointIndex); float y=event.getY(pointIndex); X=x; Y=y; Log.i("aaa","X :"+X+"Y :"+Y); //获取手值的名字(ID) pointId=event.getPointerId(pointIndex); Log.i("mmmm","pointId"+pointId); if(action_code>=5){ action_code-=5; } //单点触摸时用action判断 //多点触摸时用action_code判断 switch (action_code){ case MotionEvent.ACTION_DOWN: //按下后 // //实例化圆 // Circle circle=new Circle(x,y,r,pointId); // //将圆添加到集合中 // circles.add(circle); //调用线程控制雨滴 new MyThread().start(); break; case MotionEvent.ACTION_UP: //抬起 //找到具体的圆将它从集合中移除即可 // circles.remove(get(pointId)); break; case MotionEvent.ACTION_MOVE: //移动 //找到具体的圆,时时修改圆心点坐标即可 // for (int i = 0; i <event.getPointerCount(); i++) { // int id=event.getPointerId(i);//得打具体圆的id // //从新给圆赋值圆心点坐标 // get(id).x=event.getX(i); // get(id).y=event.getY(i); // } break; } //重新调用onDraw 重绘 // invalidate(); //子线程中重新绘制 postInvalidate(); return true; } //定义一个方法,通过pointId返回具体的圆 public Circle get(int pointId){ for (Circle circle : circles) { if(circle.pointId==pointId){ return circle; } } return null; } class MyThread extends Thread{ @Override public void run() { //实例化圆(x y就是手值的坐标 r是默认大小,手指下标) Circle circle=new Circle(X,Y,r,pointId); //将圆添加到集合中 circles.add(circle); //执行下降 while(true){ //拿到圆的圆心个 try { System.out.println("子线程名称:::"+Thread.currentThread().getName()); Circle c=get(pointId); //得到刚刚画的圆 c.x=X; // c.y=c.y+10; c.r=c.r+5; Log.i("bbbb"," X坐标"+c.x+"Y坐标 "+c.y); sleep(200); //20毫秒 postInvalidate(); } catch (InterruptedException e) { e.printStackTrace(); } } } } }
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。