明確な内容

Question

ここに私のコードです：

public class RT extends Activity implements OnTouchListener{ 

    DrawPanel dp; 
    private ArrayList<Path> pointsToDraw = new ArrayList<Path>(); 
    private Paint mPaint; 
    Path path; 


    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     // TODO Auto-generated method stub 
     super.onCreate(savedInstanceState); 
     dp = new DrawPanel(this); 
     dp.setOnTouchListener(this); 
     getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN); 
     requestWindowFeature(Window.FEATURE_NO_TITLE); 
     mPaint = new Paint(); 
     mPaint.setDither(true); 
     mPaint.setColor(Color.WHITE); 
     mPaint.setStyle(Paint.Style.STROKE); 
     mPaint.setStrokeJoin(Paint.Join.ROUND); 
     mPaint.setStrokeCap(Paint.Cap.ROUND); 
     mPaint.setStrokeWidth(30); 

     TextView tv1 = new TextView(this); 
     tv1.setText("Generated Text Goes Here"); 
     tv1.setTextSize(30); 
     tv1.setTextColor(Color.WHITE); 
     tv1.setGravity(Gravity.BOTTOM); 
     tv1.setId(R.id.TGText); 

     LinearLayout ll = new LinearLayout(this); 
     ll.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 


     Button b1 = new Button(this); 
     b1.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 
     b1.setTextSize(20); 
     b1.setText("Generate"); 
     b1.setTextColor(Color.WHITE); 
     b1.setId(R.id.TGButton); 
     b1.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       // TODO Auto-generated method stub 
      } 
     }); 

     ll.addView(b1); 

     FrameLayout fl = new FrameLayout(this); 
     fl.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT)); 
     fl.addView(dp); 
     fl.addView(tv1); 
     fl.addView(ll); 
     setContentView(fl); 

    } 

    @Override 
    protected void onPause() { 
     // TODO Auto-generated method stub 
     super.onPause(); 
     dp.pause(); 
    } 



    @Override 
    protected void onResume() { 
     // TODO Auto-generated method stub 
     super.onResume(); 
     dp.resume(); 
    } 



    public class DrawPanel extends SurfaceView implements Runnable{ 

     Thread t = null; 
     SurfaceHolder holder; 
     boolean isItOk = false ; 

     public DrawPanel(Context context) { 
      super(context); 
      // TODO Auto-generated constructor stub 
      holder = getHolder(); 
     } 

     @Override 
     public void run() { 
      // TODO Auto-generated method stub 
      while(isItOk == true){ 

       if(!holder.getSurface().isValid()){ 
        continue; 
       } 

       Canvas c = holder.lockCanvas(); 
       c.drawARGB(255, 0, 0, 0); 
       onDraw(c); 
       holder.unlockCanvasAndPost(c); 
      } 
     } 

     @Override 
     protected void onDraw(Canvas canvas) { 
      // TODO Auto-generated method stub 
      super.onDraw(canvas); 
      synchronized(pointsToDraw) 
      { 
       for (Path path : pointsToDraw) { 
        canvas.drawPath(path, mPaint); 
      } 
      } 
     } 

     public void pause(){ 
      isItOk = false; 
      while(true){ 
       try{ 
        t.join(); 
       }catch(InterruptedException e){ 
        e.printStackTrace(); 
       } 
       break; 
      } 
      t = null; 
     } 

     public void resume(){ 
      isItOk = true; 
      t = new Thread(this); 
      t.start(); 

     } 

     public void clearCanvas(){ 
      Canvas c = holder.lockCanvas(); 
      c.drawColor(Color.BLACK); 
      holder.unlockCanvasAndPost(c); 
      invalidate(); 
     } 



    } 


    @Override 
    public boolean onTouch(View v, MotionEvent me) { 
     synchronized(pointsToDraw) 
     { 
     // TODO Auto-generated method stub 
     if(me.getAction() == MotionEvent.ACTION_DOWN){ 
      path = new Path(); 
      path.moveTo(me.getX(), me.getY()); 
      //path.lineTo(me.getX(), me.getY()); 
      pointsToDraw.add(path); 
     }else if(me.getAction() == MotionEvent.ACTION_MOVE){ 
      path.lineTo(me.getX(), me.getY()); 
     }else if(me.getAction() == MotionEvent.ACTION_UP){ 
      //path.lineTo(me.getX(), me.getY()); 
     } 
     } 
     return true; 

    } 

    @Override 
    public void onBackPressed() { 
     return; 
    } 


} 

しかし、それは動作しません。親切に助けてください！ :-)

Answer 1

onDraw()は常に呼び出され、その都度、すべてpointsToDrawを描画します。

キャンバスをクリアしたい場合は、clearCanvas()のpointsToDrawをクリアするなどしてキャンバスを停止する必要があります。