I am using this code to scale the view :
view.transform = CGAffineTransform(scaleX: 2, y: 2)
It scales the view perfectly, But problem is that:
If I rotate the view first and then scale it, in this case also scaling works as required but it resets the rotation.
It should not reset the rotation.
You are creating a transform that only has a scale and you are then applying just that scale to the view.
You want to apply the scale transform to the existing transform.
view.transform = view.transform.scaledBy(x: 2, y: 2)
Related
I have this code to rotate imageView around its axis (center of image):
transform.m34 = 1.0 / -2000.0
self.imageRevealed1.layer.transform = CATransform3DMakeRotation(CGFloat(Double.pi), 0.0, 1.0, 0.0)
But I need rotate imageView around its left side. How to do it?
You should modify the view anchorPoint before set the layer transform. Example, in your case, the anchorPoint should set CGPoint(x: 0, y: 0.5), then set transform.
I am building a custom UIView that you can rotate and resize. I can resize the UIView by dragging the corners of the UIView. I calculate how much I have dragged then change the frame of the UIView accordingly.
However, I am running into problems once I added a rotation gesture recognizer to the view. If I rotate or apply a transform to the view, I no longer know how to calculate drag distance and change the frame of the view. How could I calculate the width and height change between my new view and the original view when things are put at an added angle or if they have some other transform, like a translation transform?
I thought of possibilities to set the view's transform back to .identity, change the size of the view, then re-apply its transform, but I'm not sure how to actually go about implementing this.
After applying transform you can not use frame
You have two options
1) First Calculate everything using center of your view
2) As you know apply identity and change frame
for point 2 I have added example that might helpful to you
let transform = imageView.transform
imageView.transform = CGAffineTransform.identity
var rect: CGRect = imageView.frame
rect = // Change Rect here
imageView.frame = rect // Assign it
imageView.transform = transform // Apply Transform
I am trying to flip a scaled and rotated uiview on the horizontal axis.
Here is the code being used -
CGFloat xScale = selectedFrame.transform.a;
CGFloat yScale = selectedFrame.transform.d;
selectedFrame.layer.transform = CATransform3DScale(CATransform3DMakeRotation(M_PI, 0, 1, 0),xScale, yScale,-1);
The output of this is that the view flips properly and the original scale factor is also manitained but the rotation isnt.
Here are the images to explain the problem -
Original Image (The tiger view has to be flipped on the horizontal axis) -
Flipped image after above code (see that the scale is maintained but the rotation angle isnt and the image s flipped properly) -
Any help would be really appreciated!
To flip the image you are using a rotation of M_PI around the Y axis. To rotate the image, you need to apply another different rotation around the Z axis. These are two different transforms. You can combine them using CATransform3DConcat. Then you can scale the resulting transform.
CATransform3D transform = CATransform3DConcat(CATransform3DMakeRotation(zRotation, 0, 0, 1),CATransform3DMakeRotation(M_PI, 0, 1, 0));
[layer setTransform:CATransform3DScale(transform,xScale, yScale,1)];
The problem with your original code is that you are only applying the Y axis transform.
I'm sure there is a more elegant way to do this, but this works on my simulator.
I'm trying to scale a view Horizontally but i'm not getting the results i expected.
view.bounds = CGRectMake(view.bounds.origin.x, view.bounds.origin.y , view.bounds.size.width * scaleX, view.bounds.size.height );
view.center = CGPointMake(view.bounds.origin.x, view.center.y);
As you can see at the code above, i want to scale the view just to the right side. This is why i changed the center of the view.
The problem is that the view stills scaling to both sides!
I did the same logic to scale another UIView vertically and got the result i expected.
Just found the problem.
when setting certer, the new point must be relative to frame, not bounds.
so, i get the code:
view.center = CGPointMake(-view.frame.origin.x, view.center.y);
Hope it helps somebody..
Thx for help
If the origin of your view's frame is in the top-left (which is the default), increasing the width of your view should scale it to the right only.
This should work:
view.frame = CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width * scaleX, view.frame.size.height);
You do not need to adjust the origin/center point to scale only to the right.
Try using an affine transform instead:
view.transform = CGAffineTransformMakeScale(scaleX, 1)
And then setting the center.
I'm developing an animated column bar chart and i having some trouble.
The bars show up with an scale animation. At the beginning all columns have 1 point size and will scale till a predefined height.
The point is: I want to draw a gradient into the columns (They are subclasses of UIView) and want the scale animation to recalculate the gradient.
Until now, i have drawn the gradient, but when the column scale, the gradient does not scale with it.
As the view have 1 point height, the gradient is show as 1 color only.
Can someone give me a north to solve this issue?
Solved the problem!
i was using scale instead of changing the view's bounds..
Was
view.transform = CGAffineTransformMakeScale(1.0, scaleY.floatValue);
Must be
view.bounds = CGRectMake(view.bounds.origin.x, view.bounds.origin.y * scaleY.floatValue, view.bounds.size.width, view.bounds.size.height * scaleY.floatValue);
Where scaleY was calculated before and is a NSNumber that contains the Y scale factor.
It's not necessary to set
view.contentMode = UIViewContentModeRedraw;
Thank you DarkDusk for the help.
Try setting the contentMode:
myView.contentMode = UIViewContentModeRedraw;
This will force a redraw on every size change.