Android를 사용할 때 NoSuchMethodException이 throw됩니다.

Question

필자는 작성한 View CropView를 사용하는 Activity CropActivity를 보유하고 있습니다. CropView는 SelectorView (자체 작성)를 확장하고 SelectorView는 ImageView를 확장합니다.

CropActivity를 시작하면 NoSuchMethodException이 발생합니다. CropActivity에 대해 SelectorView를 사용할 때 오류가 발생하지 않습니다.

공용 클래스 CropView이 SelectorView를 확장하는 Cropview 클래스 {

public CropView(Context context) { 
    super(context); 
    initCropView(); 
} 

private void initCropView() { 
    setmPaintColor(Color.WHITE); 
    setsMinimumSize(metrics.densityDpi); 
    setsTouchBuffer(metrics.densityDpi/3); 
} 

@Override 
protected void onDraw(Canvas canvas) { 
    super.onDraw(canvas); 
    if (getmLeftTop().equals(0, 0)) 
     resetPoints(); 
    // draw the points on the screen; one in every corner and one in the center 
    canvas.drawRect(getmLeftTop().x, getmLeftTop().y, getmRightBottom().x, getmRightBottom().y, 
      getmPaint()); 
    canvas.drawCircle(getmLeftTop().x, getmLeftTop().y, 40, getmPaint()); 
    canvas.drawCircle(getmLeftTop().x, getmRightBottom().y, 40, getmPaint()); 
    canvas.drawCircle(getmRightBottom().x, getmLeftTop().y, 40, getmPaint()); 
    canvas.drawCircle(getmRightBottom().x, getmRightBottom().y, 40, getmPaint()); 
    canvas.drawCircle(getmCenter().x, getmCenter().y, 10, getmPaint()); 
} 

Selectorview는 한 OnCreate CropActivity

에서

public SelectorView(Context context) { 
    super(context); 
    initSelectorView(); 
} 

public SelectorView(Context context, AttributeSet attrs) { 
    super(context, attrs, 0); 
    initSelectorView(); 
} 

public SelectorView(Context context, AttributeSet attrs, int defStyle) { 
    super(context, attrs, defStyle); 
    initSelectorView(); 
} 

@Override 
protected void onDraw(Canvas canvas) { 
    super.onDraw(canvas); 
} 

/** 
* Initializes the cropview and variables. 
*/ 
private void initSelectorView() { 
    mPaint.setStyle(Style.STROKE); 
    mPaint.setStrokeWidth(5); 
    mLeftTop = new Point(); 
    mRightBottom = new Point(); 
    mCenter = new Point(); 
    mScreenCenter = new Point(); 
    mPrevious = new Point(); 
} 

@Override 
public boolean onTouchEvent(MotionEvent event) { 
    int eventaction = event.getAction(); 
    switch (eventaction) { 
    // set the touch point 
     case MotionEvent.ACTION_DOWN: 
      mPrevious.set((int) event.getX(), (int) event.getY()); 
      break; 

니펫을

protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_crop); 

    mContext = this; 
    mCropView = new CropView(this); 
    mFile = new File(getIntent().getStringExtra("imgpath")); 
    mBitmaps = new ArrayList<Bitmap>(); 
    mTasks = new ArrayList(); 
    mNumberOfCores = Runtime.getRuntime().availableProcessors(); 
    mProgressDialog = new ProgressDialog(mContext); 
    mProgressDialog.setTitle("Enhancing image"); 
    mBitmapDrawable = null; 
    mBitmapDrawable = (BitmapDrawable) Drawable.createFromPath(mFile.getAbsolutePath()); 

    mCropView = (CropView) findViewById(R.id.image_preview); 
    mCropView.setImageDrawable(mBitmapDrawable); 

    mCropButton = (Button) findViewById(R.id.button_crop); 

Answer 1

사용자 정의보기 XML을 통해 비정상적으로 다음과 같은 생성자가 필요합니다 :

ViewName(Context) 
ViewName(Context, AttributeSet) 
ViewName(Context, AttributeSet, int) 

첫 번째 질문 만 있으니 예외는 두 번째 질문이 CropView에 누락 된 것 같습니다.