The dashed rectangle is the parent group and inside, there is a label. Its x is negative.
Now, what I want to do is relocation the outside group to the contents' top-left point and meanwhile the contents' move back to the outside group's (0,0) point. The result looks like everything keeps the same position as before.but in fact, both inside content and outside group is moved.
It is easy to realize in flash, however, in flex i got trouble.
The function "getRect" returns wrong values.it's never return the correct position the inside content is.(like the thumb shows,the position should be like [-70,50])
(Feel free to correct me because I'm not sure what you want to accomplish here)
If your Label (let's say it is called myLabel) is correctly located directly inside of your Group, simply calling myLabel.x will return the X-coordinate of the label compared to its parent (which is your Group here, so you should get -70).
Then if you want to move the label so it fits into your Group viewport, you have two solutions:
Either you manually set myLabel.x = 0 and myLabel.y = 0. In this case the label will actually be moved at the Group origin.
Either you retrieve the matrix of your label component to call its .translate(dx, dy) function. Using the matrix functions will modify the way your Label is displayed, but its position will remain unchanged (More information about that on this page).
Short answer: If you don't care about keeping the original position of your label, just set myLabel.x = 0 and myLabel.y = 0 and it should be moved correctly.
Related
I am using map bounds to display markers that fall within the current viewport. Upon zooming or panning the bounds are recalculated and the markers that fall within these bounds are redrawn, effectively hiding any not contained within the viewport.
I would like to do it so that the markers draw slightly out of the current viewport, however this would involve extending the bounds equally from all sides rather than using bounds.extend(point). Is this possible?
//I would like to extend this value in order to draw features that are slightly off the viewport
var bounds = map.getBounds()
//This is how I am currently extending the bounds, it works but I am unsure if it is the correct way.
bounds.b.b = bounds.b.b - 0.5
bounds.b.f = bounds.b.f + 0.5
bounds.f.b = bounds.f.b - 0.5
bounds.f.f = bounds.f.f + 0.5
//Determining whether the feature lies within the current viewport
var result = bounds.contains(Featurecenter)
center = null
//If the feature lies within the viewport
if (result) {
Feature.setMap(map) //Making the feature visible on the map
}
Don't use b, f and such, which are undocumented properties, instead use documented methods such as getNorthEast(), getSouthWest() then lat() and lng() when you need to extract coordinates from a bounds object.
I don't know of any other method to extend a bounds object than to pass new coordinates to it (see below).
The LatLngBounds object has an extend() method that you must use to achieve what you want.
We don't know of "how much" you need to extend the bounds; depending on that, and on the current zoom level when you want to extend your bounds, you will probably need to do some maths.
If you need to extend your bounds by a given (and constant) distance, whatever zoom level is currently set, I suggest you to read some other Q/A that explain how to do that. For example:
Google maps distance based on the zoom level
Google Maps V3 - How to calculate the zoom level for a given bounds
I would like to move a button's position (X & Y) within a specific area of a view object.
What I've done so far is, I've added a view object on to my main screen and I've also added a button inside the view, so far OK.
Now, I managed to get the bounds of the view object and I know the size of my button say (50x50). So what I want is, when I click on the button, it should move to another random location but within the view object, it should not move outside the view object boundaries. Right now what happens in my button appears to be moving a portion of it outside the view object based on the random X & Y.
Any help will be appreciated.
I managed to get it as well. Here is how I did it:
I created a function which I pass the shape to and return the location that I want the piece to move to which is within the bounds of the view.
func randomizeLocation(shape: CGRect) -> CGPoint {
let randomX = arc4random_uniform(UInt32(gameBoard.frame.width - shape.width)) + UInt32(shape.width / 2)
let randomY = arc4random_uniform(UInt32(gameBoard.frame.height - shape.height)) + UInt32(shape.height / 2)
return CGPointMake(CGFloat(randomX), CGFloat(randomY))
}
Just in speaking about the x coordinate (left/right)
The logic here is that arc4random_uniform will return a random # between 0 and the given number (- 1).
But you don't want a number starting at zero because that would put the object off the edge of the screen to the left by 1/2. So, if you add 1/2 of the width to the overall function, you will never go off to the left side of the screen.
To keep from going off the right side of the screen you want a maximum number of the screen width minus 1/2 of the width of the object. To get this, you must specify the number you pass to the arc4random function as minus the whole width of the shape, because when you add back half, you are shifting by 1/2 of the width of your object on both sides (minimum and maximum return value).
So to use this function, take your object, lets say a UILabel and set its center to this functions result as such:
let myLabel = UIButton(type: .Custom)
myLabel.frame = CGRectMake(100, 100, 100, 100)
myLabel.center = randomizeLocation(myLabel.bounds)
And that it. Btw, I did not account for the -1 in the return b/c i figured the one pixel was too insignificant to bother with..
A simple question as i am developing a java application based on dcm4che ...
I want to calculate/find the "position" of a dicom image into its sequence (series). By position i mean to find if this image is first, second etc. in its series. More specifically i would like to calculate/find:
Number of slices into a Sequence
Position of each slice (dicom image) into the Sequence
For the first question i know i can use tag 0020,1002 (however it is not always populated) ... For the second one?
If you are dealing with volumetric image series, best way to order your series is to use the Image Position (Patient) (0020, 0032). This is a required Type 1 tag (should always have value) and it is part of the image plane module. It will contain the X, Y and Z values coordinates representing the upper left corner of the image in mm. If the slices are parallel to each other, only one value should change between the slices.
Please note that the Slice Location (0020, 1041) is an optional (Type 3) element and it may not exist in the DICOM file.
We use the InstanceNumber tag (0x0020, 0x0013) as our first choice for the slice position. If there is no InstanceNumber, or if they are all the same, then we use the SliceLocation tag (0x0020, 0x1041). If neither tag is available, then we give up.
We check the InstanceNumber tag such that the Max(InstanceNumber) - Min(InstanceNumber) + 1 is equal to the number of slices we have in the sequence (just in case some manufacturers start counting at 0 or 1, or even some other number). We check the SliceLocation the same way.
This max - min + 1 is then the number of slices in the sequence (substitute for tag ImagesInAcquisition 0x0020, 0x1002).
Without the ImagesInAcquisition tag, we have no way of knowing in advance how many slices to expect...
I would argue that if the slice location is available, use that. It will be more consistent with the image acquisition. If it is not available, then you'll have to use or compute from the image position (patient) attribute. Part 3 section C.7.6.2.1 has details on these attributes.
The main issue comes when you have a series that is oblique. If you just use the z-value of the image position (patient), it may not change by the slice thickenss/spacing between slices attributes, while the slice location typically will. That can cause confusion to end users.
I'm trying to make a subclass of QSlider that allows the user to insert "bookmarks" so they can remember significant locations on the slider. I've run into a problem painting the tabs on the slider - using QStyle.sliderPositionFromValue, I get a value but it is slightly inaccurate. If I'm on the left side of the slider, the tab is painted too far left, and on the right side it is painted too far right. I believe this is because QSlider.width() returns the width of the whole object, including the small offsets at the left and right. So width() might return 630 pixels, when the length of the slider itself is really 615.
This is the code I'm using to get the pixel position and draw a line across the slider.
pos = QStyle.sliderPositionFromValue(self.minimum(),self.maximum(),sliderIndex,self.width())
painter.drawLine(pos,0,pos,self.height())
I've been looking at the QT Source here starting on line 2699 and it seems like I need to be using the PixelMetric class from QStyle. I've tried using:
self.style().pixelMetric(QStyle.PM_SliderSpaceAvailable)
But that returns 0, which is clearly not the value I need.
I'd appreciate any advice.
Edit: As suggested in the comments, I changed the call to:
self.style().pixelMetric(QStyle.PM_SliderSpaceAvailable, QStyleOption(1,QStyleOption.SO_Slider),self)
This however, returns -14, which also doesn't match for the value of the offsets (I tried using self.width()-14 but the offset remains.
I am working on a qwtPlot and have implemented custom scrollbars to illustrate the position of things on the plot when zooming in (in regards to the whole thing - so basically the percentage).
Now, everything works fine, apart from the moment, when I do any zooming or panning right at the beginning (or simply when I see the whole plot and then I want to zoom in).
This is a slot I am using to refresh the appearance of the scrollbar:
void ScrollHorizontal::refreshAfterChanges() {
setValue(myPlot->getLowerBound(QwtPlot::xBottom));
setPageStep(myPlot->get_X_delta());
setSingleStep(myPlot->get_X_delta()/10);
setMaximum(myPlot->dataFromSources->lastTimeValMicro()-pageStep());
update();
printV("HorizontalScroll::setValue",myPlot->getLowerBound(QwtPlot::xBottom));
printV("value", value());
printV("pageStep", pageStep());
in the constructor I set the maximum to 0 (just in case, but it doesn't change anything)
The last 3 lines print out some values useful for debugging. What I found out thanks to them is that the slot is executed correctly, but the setValue(int) function doesn't work as I would expect it to:
//printed values right after starting the program
HorizontalScroll::setValue=0
value=0
pageStep=7320
//printed values after using the zoomer once
HorizontalScroll::setValue=956.316
value=0
pageStep=2225
Then, when I move the plot a tiny bit, e.g. zoom it 1.1 times, the setValue works properly and value() return the same thing I set. But if I go to the 100% view (the starting point) I get the same problems again.
Just to illustrate it, here are some screenshots:
http://tinypic.com/view.php?pic=2znph7s&s=8#.UvNkDoZhauY
(100% view, right before zooming in)
http://tinypic.com/view.php?pic=ke7nn9&s=8#.UvNkYIZhauY
(badly set qscrollbar)
Ok - problem was caused by the line
setMaximum(myPlot->dataFromSources->lastTimeValMicro()-pageStep());
It was setting the maximum to 0 sometimes. why? I wanted the slider to take up the whole length of the scrollbar so that at the beginning when the plot was shown in 100% view, you couldn't scroll it and I could achieve that by setting the pagestep to my plot's maximum value and the maximum to 0.
But that caused the setValue(int)problem - you can't set a value bigger than the maximum.
So what finally worked for me is:
double valueToSet=myPlot->getLowerBound(QwtPlot::xBottom);
if(valueToSet>maximum())
setMaximum(valueToSet);
setValue(myPlot->getLowerBound(QwtPlot::xBottom));
setPageStep(myPlot->get_X_delta());
setSingleStep(myPlot->get_X_delta()/10);
setMaximum(myPlot->dataFromSources->lastTimeValMicro()-pageStep());
update();