В onDraw () вы можете преобразовать свой холст, используя матрицу. А в onTouch () вы можете преобразовать обратно экранные координаты, используя обратную матрицу.
private static class MyView extends View {
private final Paint texPaint = new Paint(){{
setTextSize(60);
setColor(Color.BLACK);
}};
private final Paint rectPaint = new Paint(){{
setStrokeWidth(20);
setColor(Color.RED);
setStyle(Paint.Style.STROKE);
}};
private final Matrix matrix = new Matrix();
private final RectF rect = new RectF(0, 0, 400, 150);
public MyView(Context context) {
super(context);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
matrix.reset();
matrix.postRotate(45);
matrix.postScale(1.5f, 1.5f, 0, 0);
matrix.postTranslate(w/2, h/2);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.save();
canvas.concat(matrix);
canvas.drawRect(rect, rectPaint);
//Bottom line of the drawn text is at y, if you want the text to inside the rect
// increase the y by the text height, textHeight is the textSize
canvas.drawText("SomeText", 0, texPaint.getTextSize(), texPaint);
canvas.restore();
}
@Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getActionMasked() == MotionEvent.ACTION_UP) {
float x = event.getX();
float y = event.getY();
Toast.makeText(getContext(), isInsideRegion(x, y) ? "Inside" : "Outside", Toast.LENGTH_SHORT).show();
}
return true;
}
private boolean isInsideRegion(float x, float y) {
Matrix invertedMatrix = new Matrix();
if (!matrix.invert(invertedMatrix)) {
throw new RuntimeException("Matrix can't be inverted");
}
float[] point = {x, y};
invertedMatrix.mapPoints(point);
return rect.contains(point[0], point[1]);
}
}