Comment nettoyer la peinture au doigt?

Question

Je suis nouveau à android, j'ai préparé une vue de peinture en utilisant le doigt avec l'aide de FingerPaint.java dans Api Demo.Il fonctionne bien.

Le même point de vue contient un bouton (clair), si l'on clique sur la peinture bouton sera claire (sceen vide et un bouton) .Mon problème est de savoir comment effacer le code de la vue paint.My est,

public class MyDraw extends View { 

    Paint mPaintAlphabet = new Paint(); 

    private static final float MINP = 0.25f; 
    private static final float MAXP = 0.75f; 

    float x, y; 
    float mX, mY; 
    private static final float TOUCH_TOLERANCE = 4; 

    private Bitmap mBitmap; 
    Canvas mCanvas; 
    Path mPath; 
    Paint mBitmapPaint; 

    public MyDraw(Context context) { 
     super(context); 

     mBitmap = Bitmap.createBitmap(320, 480, Bitmap.Config.ARGB_8888); 
     mCanvas = new Canvas(mBitmap); 
     mPath = new Path(); 
     mBitmapPaint = new Paint(Paint.DITHER_FLAG); 


    } 

    public MyDraw(Context context, AttributeSet attributeSet) { 
     super(context, attributeSet); 

     mBitmap = Bitmap.createBitmap(480, 480, Bitmap.Config.ARGB_8888); 
     mCanvas = new Canvas(mBitmap); 
     mPath = new Path(); 
     mBitmapPaint = new Paint(Paint.DITHER_FLAG); 

     mPaintAlphabet.setDither(true); 
     mPaintAlphabet.setColor(0xFFFF0000); 
     mPaintAlphabet.setStyle(Paint.Style.STROKE); 
     mPaintAlphabet.setStrokeJoin(Paint.Join.ROUND); 
     mPaintAlphabet.setStrokeCap(Paint.Cap.ROUND); 
     mPaintAlphabet.setStrokeWidth(3); 
     mPaintAlphabet.setTextSize(350); 

    } 

    protected void onSizeChanged(int w, int h, int oldw, int oldh) { 
     super.onSizeChanged(w, h, oldw, oldh); 
    } 

    public void onDraw(Canvas canvas) { 

      if (MyAlphabetsActivity.mArryLstAlphabets.get(
       MyAlphabetsActivity.mAlphaIndex).equals("I")) { 

      canvas.drawText((String) MyAlphabetsActivity.mArryLstAlphabets 
        .get(MyAlphabetsActivity.mAlphaIndex), 180, 300, 
        mPaintAlphabet); 

     } else if (MyAlphabetsActivity.mArryLstAlphabets.get(
       MyAlphabetsActivity.mAlphaIndex).equals("J")) { 

      canvas.drawText((String) MyAlphabetsActivity.mArryLstAlphabets 
        .get(MyAlphabetsActivity.mAlphaIndex), 180, 300, 
        mPaintAlphabet); 

     } else { 
      canvas.drawText((String) MyAlphabetsActivity.mArryLstAlphabets 
        .get(MyAlphabetsActivity.mAlphaIndex), 120, 300, 
        mPaintAlphabet); 
     } 

     System.out.println("in on draw"); 
     System.out.println("path is----" + mPath); 

     canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint); 

     canvas.drawPath(mPath, MyAlphabetsActivity.mPaint); 
    } 

    private void touch_start(float x, float y) { 
     mPath.reset(); 
     System.out.println("mPath-----"+mPath); 
     mPath.moveTo(x, y); 
     mX = x; 
     mY = y; 
    } 

    private void touch_move(float x, float y) { 
     float dx = Math.abs(x - mX); 
     float dy = Math.abs(y - mY); 
     if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) { 
      mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2); 
      mX = x; 
      mY = y; 
     } 
    } 

    private void touch_up() { 
     mPath.lineTo(mX, mY); 
     // commit the path to our offscreen 
     mCanvas.drawPath(mPath, MyAlphabetsActivity.mPaint); 
     // kill this so we don't double draw 
     mPath.reset(); 
    } 

    @Override 
    public boolean onTouchEvent(MotionEvent event) { 
     x = event.getX(); 
     y = event.getY(); 

     switch (event.getAction()) { 
     case MotionEvent.ACTION_DOWN: 
      touch_start(x, y); 
      invalidate(); 
      break; 
     case MotionEvent.ACTION_MOVE: 
      touch_move(x, y); 
      invalidate(); 
      break; 
     case MotionEvent.ACTION_UP: 
      touch_up(); 
      invalidate(); 
      break; 
     } 
     return true; 
    } 


} 

Et mon code d'activité est,

public class MyAnimViewActivity extends Activity 
     {  
    public static Paint  mPaint; 
    private MaskFilter mEmboss; 
    private MaskFilter mBlur; 
    Button mBtnClear; 
    MyDraw mMyDraw=new MyDraw(); 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(new MyOwnView(this)); 

     mPaint = new Paint(); 
     mPaint.setAntiAlias(true); 
     mPaint.setDither(true); 
     mPaint.setColor(0xFFFF0000); 
     mPaint.setStyle(Paint.Style.STROKE); 
     mPaint.setStrokeJoin(Paint.Join.ROUND); 
     mPaint.setStrokeCap(Paint.Cap.ROUND); 
     mPaint.setStrokeWidth(12); 

     mEmboss = new EmbossMaskFilter(new float[] { 1, 1, 1 }, 
             0.4f, 6, 3.5f); 

     mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL); 

     mBtnClear=(Button)findViewById(R.id.btnClear); 

     mBtnClear.setOnClickListener(new OnClickListener() { 

      public void onClick(View v) { 
       // TODO Auto-generated method stub 
       switch (v.getId()) { 
       case R.id.btnClear: 
        mMyDraw.mPath.reset(); 

        break; 

       } 
      } 
     }); 
    } 
} 

S'il vous plaît aider me..Thanks à l'avance

Answer 1

faire une fonction publique dans votre classe de dessin personnalisé nommé clearDrawing(); et écrivez ceci:

mBitmap = null; 
mPath = null; 
mBitmap = Bitmap.createBitmap(480, 480, Bitmap.Config.ARGB_8888); 
mPath = new Path(); 

appelez maintenant clearDrawing() pour réinitialiser le contrôle de dessin.