// If the cropping rectangle's size changed significantly, change the
// view's center and scale according to the cropping rectangle.
private void centerBasedOnHighlightView(HighlightView hv)
{
Rect drawRect = hv.DrawRect;
float width = drawRect.Width();
float height = drawRect.Height();
float thisWidth = Width;
float thisHeight = Height;
float z1 = thisWidth / width * .6F;
float z2 = thisHeight / height * .6F;
float zoom = Math.Min(z1, z2);
zoom = zoom * this.GetScale();
zoom = Math.Max(1F, zoom);
if ((Math.Abs(zoom - GetScale()) / zoom) > .1)
{
float[] coordinates = new float[]
{
hv.CropRect.CenterX(),
hv.CropRect.CenterY()
};
ImageMatrix.MapPoints(coordinates);
ZoomTo(zoom, coordinates[0], coordinates[1], 300F);
}
ensureVisible(hv);
}
protected override void PostTranslate(float deltaX, float deltaY)
{
base.PostTranslate(deltaX, deltaY);
for (int i = 0; i < hightlightViews.Count; i++)
{
HighlightView hv = hightlightViews[i];
hv.matrix.PostTranslate(deltaX, deltaY);
hv.Invalidate();
}
}
// Pan the displayed image to make sure the cropping rectangle is visible.
private void ensureVisible(HighlightView hv)
{
Rect r = hv.DrawRect;
int panDeltaX1 = Math.Max(0, IvLeft - r.Left);
int panDeltaX2 = Math.Min(0, IvRight - r.Right);
int panDeltaY1 = Math.Max(0, IvTop - r.Top);
int panDeltaY2 = Math.Min(0, IvBottom - r.Bottom);
int panDeltaX = panDeltaX1 != 0 ? panDeltaX1 : panDeltaX2;
int panDeltaY = panDeltaY1 != 0 ? panDeltaY1 : panDeltaY2;
if (panDeltaX != 0 || panDeltaY != 0)
{
PanBy(panDeltaX, panDeltaY);
}
}
private void addHighlightView()
{
Crop = new HighlightView(imageView);
int width = bitmap.Width;
int height = bitmap.Height;
Rect imageRect = new Rect(0, 0, width, height);
// make the default size about 4/5 of the width or height
int cropWidth = Math.Min(width, height) * 4 / 5;
int cropHeight = cropWidth;
if (aspectX != 0 && aspectY != 0)
{
if (aspectX > aspectY)
{
cropHeight = cropWidth * aspectY / aspectX;
}
else
{
cropWidth = cropHeight * aspectX / aspectY;
}
}
int x = (width - cropWidth) / 2;
int y = (height - cropHeight) / 2;
RectF cropRect = new RectF(x, y, x + cropWidth, y + cropHeight);
Crop.Setup(imageView.ImageMatrix, imageRect, cropRect, aspectX != 0 && aspectY != 0);
imageView.ClearHighlightViews();
Crop.Focused = true;
imageView.AddHighlightView(Crop);
}
public void AddHighlightView(HighlightView hv)
{
hightlightViews.Add(hv);
Invalidate();
}
public override bool OnTouchEvent(MotionEvent ev)
{
CropImage cropImage = (CropImage)context;
if (cropImage.Saving)
{
return false;
}
switch (ev.Action)
{
case MotionEventActions.Down:
for (int i = 0; i < hightlightViews.Count; i++)
{
HighlightView hv = hightlightViews[i];
var edge = hv.GetHit(ev.GetX(), ev.GetY());
if (edge != HighlightView.HitPosition.None)
{
motionEdge = edge;
mMotionHighlightView = hv;
mLastX = ev.GetX();
mLastY = ev.GetY();
mMotionHighlightView.Mode =
(edge == HighlightView.HitPosition.Move)
? HighlightView.ModifyMode.Move
: HighlightView.ModifyMode.Grow;
break;
}
}
break;
case MotionEventActions.Up:
if (mMotionHighlightView != null)
{
centerBasedOnHighlightView(mMotionHighlightView);
mMotionHighlightView.Mode = HighlightView.ModifyMode.None;
}
mMotionHighlightView = null;
break;
case MotionEventActions.Move:
if (mMotionHighlightView != null)
{
mMotionHighlightView.HandleMotion(motionEdge,
ev.GetX() - mLastX,
ev.GetY() - mLastY);
mLastX = ev.GetX();
mLastY = ev.GetY();
if (true)
{
// This section of code is optional. It has some user
// benefit in that moving the crop rectangle against
// the edge of the screen causes scrolling but it means
// that the crop rectangle is no longer fixed under
// the user's finger.
ensureVisible(mMotionHighlightView);
}
}
break;
}
switch (ev.Action)
{
case MotionEventActions.Up:
Center(true, true);
break;
case MotionEventActions.Move:
// if we're not zoomed then there's no point in even allowing
// the user to move the image around. This call to center puts
// it back to the normalized location (with false meaning don't
// animate).
if (GetScale() == 1F)
{
Center(true, true);
}
break;
}
return true;
}