Android 学习笔记（七）：绘制基本图形

基础中的基础，代码中有详细解释，

[java] public class DrawingActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //XML布局时用setContentView(int layoutResID)
        //还有 setContentView(View view)
        //和 setContentView(View view, ViewGroup.LayoutParams params)
        setContentView(new Drawing(this));
    }
}
//新建一个类Drawing继承自View
class Drawing extends View{
    //创建一个画笔
    Paint paint=new Paint();
    //构造方法
    public Drawing(Context context) {
        super(context);
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        //设置画布颜色
        canvas.drawColor(Color.GRAY);
        //设置画笔颜色
        paint.setColor(Color.CYAN);
        paint.setTextSize(16);
        //文本
        canvas.drawText("绘制文本", 120, 20, paint);
        //直线
        canvas.drawLine(120, 40, 220, 40, paint);
        //矩形
        canvas.drawRect(100, 80, 200, 120, paint);
        //圆形 www.zzzyk.com
        canvas.drawCircle(90, 200, 30, paint);
        //绘制一个椭圆

        canvas.drawOval(new RectF(120,200,220,260), paint);
        //路径
        Path p=new Path();
        p.moveTo(50, 0);
        p.lineTo(25, 100);
        p.lineTo(100, 40);
        p.lineTo(0, 40);
        p.lineTo(75, 100);
        p.lineTo(50, 0);
        canvas.drawPath(p, paint);
    }

}

摘自柒尐狐的专栏

补充：移动开发 , Android ,