Android编程之手绘 ，画图

不记得哪里获得的一段代码，是通过手指触屏在手机上绘制内容，贴出原代码供大家参考：

[java]
view plaincopy

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.view.MotionEvent;
import android.view.View;

class TestView extends View {

public Canvas canvas;
public Paint p;
private Bitmap bitmap;
float x,y;
int bgColor;

public TestView(Context context) {
super(context);
bgColor = Color.WHITE; //设置背景颜色
bitmap = Bitmap.createBitmap(480, 480, Bitmap.Config.ARGB_8888); //设置位图，线就画在位图上面，第一二个参数是位图宽和高
canvas=new Canvas();
canvas.setBitmap(bitmap);
p = new Paint(Paint.DITHER_FLAG);
p.setAntiAlias(true); //设置抗锯齿，一般设为true
p.setColor(Color.RED); //设置线的颜色
p.setStrokeCap(Paint.Cap.ROUND); //设置线的类型
p.setStrokeWidth(8); //设置线的宽度

}

//触摸事件
@Override
public boolean onTouchEvent(MotionEvent event) {

if (event.getAction() == MotionEvent.ACTION_MOVE) { //拖动屏幕
canvas.drawLine(x, y, event.getX(), event.getY(), p); //画线，x，y是上次的坐标，event.getX(), event.getY()是当前坐标
invalidate();
}

if (event.getAction() == MotionEvent.ACTION_DOWN) { //按下屏幕
x = event.getX();
y = event.getY();
canvas.drawPoint(x, y, p); //画点
invalidate();
}
if (event.getAction() == MotionEvent.ACTION_UP) { //松开屏幕
}
x = event.getX(); //记录坐标
y = event.getY();
return true;
}

@Override
public void onDraw(Canvas c) {
c.drawBitmap(bitmap, 0, 0, null);
}
}