Android 學習筆記（七）：繪製基本圖形

基礎中的基礎，代碼中有詳細解釋，

[java] public class DrawingActivity extends Activity { 
    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
        super.onCreate(savedInstanceState); 
        //XML布局時用setContentView(int layoutResID)  
        //還有 setContentView(View view)  
        //和 setContentView(View view, ViewGroup.LayoutParams params)  
        setContentView(new Drawing(this)); 
    } 
} 
//建立一個類Drawing繼承自View  
class Drawing extends View{ 
    //建立一個畫筆  
    Paint paint=new Paint(); 
    //構造方法  
    public Drawing(Context context) { 
        super(context); 
    } 
    @Override 
    protected void onDraw(Canvas canvas) { 
        super.onDraw(canvas); 
        //設定畫布顏色  
        canvas.drawColor(Color.GRAY); 
        //設定畫筆顏色  
        paint.setColor(Color.CYAN); 
        paint.setTextSize(16); 
        //文本  
        canvas.drawText("繪製文本", 120, 20, paint); 
        //直線  
        canvas.drawLine(120, 40, 220, 40, paint); 
        //矩形  
        canvas.drawRect(100, 80, 200, 120, paint); 
        //圓形 www.2cto.com   
        canvas.drawCircle(90, 200, 30, paint); 
        //繪製一個橢圓  
 
        canvas.drawOval(new RectF(120,200,220,260), paint); 
        //路徑  
        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  柒尐狐的專欄