I have several buttons and i want the lower one to placed in center Y plus 10-15 pixels.
I am trying to do this with the auto layout constraints, but i can't figure out what should be the correct constraint.
Add the Vertical Center in Container constraint (Alignment constraint button on the interface builder) to the buttons and change the constant to -10 to -15 as appropriate. You will probably need a x constraint, height constraint, and a width constraint as well.
I don't think it's possible to place an item "N points above the center." Instead, you can create a plain UIView with a transparent background and center that in your window. Give it a height of 10 points or so. Then you can use auto layout to place your buttons ~5-10 points above that.
Related
My screen layout has elements placed correctly
but when I switch to another screen, eg. iphone 7 plus
or se
things change. I've set constrains, height and witdh when I suppose I should, but apparently it does not want to cooperate with me. Please tell me what constrains and heights, widths should I set.
Add below constraint
For the red and green View You need to give Equal Width Constraint.
For Blue View at the center you need to give Center Horizontally Constraint.
For the bar at the bottom You need to give Bottom distance from the Red/Green Top Constraint.
I am new to IOS development and have the attached screen that I am developing in portrait mode only. I have fiddled around with constraints for half of today but not really got anywhere with making this work on anything other than a 5s.
Not sure if i constrain to edge of phone and/or the box at the side of the one i am trying to constrain or both!
It would be much appreciated if someone could point me in the right direction to get this to fit on all screen sizes. Landscape I think is a pipe dream at this stage:)
Here are the width constraints you should add to each button:
add a equal widths constraint for each button to the main view, then set it's multiplier to 0.5. That will make each button half the width of the screen.
for the dark blue buttons, make a leading constraint to the left edge of the view (not the margin) and set it's constant to 0.
for the light blue buttons, make a trailing constraint to the right edge of the view (not the margin) and set it's constant to 0.
For the Y positioning, you should do the following:
for the top buttons, add a vertical spacing constraint from the buttons to the title view, with the constant set to whatever you want
for each button that follows underneath, add a vertical spacing constraint to the button above it with a constant of 0
for the bottom buttons, and a vertical spacing constraint to the bottom layout guide with a constant of 0
This will adjust the height of the buttons to match the screen size / orientation while maintaining your layout. should work fine with landscape, although those buttons will be awfully skinny!
Am new to iOS & am facing it very difficult to set autolayout. Watched many videos to learn, but all of them giving solution to a specific problem. No video covers all base rules to set an UI object into it's place & with proper flow.
I came from Corona Background & used to set UI programatically very well. Am thinking here same way, but I think apple made it so difficult or people are not able to explain me properly.
Please see 2 images attached in this question & tell me rules to apply to achieve this UI. I request you people to please explain in the general manner so that my other screen can be completed using same rules.
Image 1: http://i.stack.imgur.com/MPE47.png
Image 2: http://i.stack.imgur.com/qEiCm.jpg
A really helpful guideline is
Every element should be able to figure out its position (x and y) and size (width and height).
Ensure that every element only has one way to figure out its position and size.
Remember that the autolayout of all the elements can influence each other.
The most used layout constraints are:
Top The space between the top of the view to another view.
Trailing The space between the right edge of the view to another view.
Leading The space between the left edge of the view to another
Bottom The space between the bottom edge of the view and another view
Width Assign a fix width to a view (Note that it can also be a percentage - aspect ratio)
Height Assign a fix width to a view (Can also be a percentage)
Center Horizontally Always align the view relative to the horizontal center of another view
Center Vertically Always align the view relative the the vertical center of another view
For example in your second image, say the yellow bar is a UIView called titleView.
Set the position of titleView by setting the top layout constraint to the container view. y position is set.
Set the leading constraint to the container view. x position is set.
Set the trailing constraint to the container view. The view's width will now stretch with the screen size. Thus width can now be determined.
Set height to 50. Height is set.
Now... If you also set the width of this view, it will cause the layoutConstraints to break, because you have redefined the width constraint. Some of the constraints will then be ignored.
Another example of how layoutConstraints might influence each other. Lets look at determining the y positions of the second image.
Say titleView has a top constraint to the container + height of 50.
currentCampaignView has a top constraint to the bottom of titleView. (Use vertical spacing) + equal height to titleView. (y + height can be calculated)
the 5 buttons have equal heights. Top buttons have Top space to Bottom of currentCampaignView. Centre buttons have Top space to bottom of top buttons. Bottom button have Top space to bottom of centre buttons.
startCampaignView has equal height to currentCampaignView. Top constraint to bottom of bottom button and Bottom constraint to container view.
Note that because views and buttons have equal heights, all are considered when determining the height. Thus it is very important that they are all interlinked and that the entire height that can be used is specified. In this case it is specified by the first element titleView that has a Top Constraint to the Container view (of which the height should be known) and the last element, startCampaignView, that has a Bottom constraint to the Container view. Because all the views in between are linked on y position and height, the view can work out what each view's height and y position should be.
One more example. (Your first image)
topLeftButton Set the top constraint to Superview. (y), Set the leading constraint to Superview (x), Set height = 100 (height), Set equal width to topRightButton (Note that we do not quite have the width yet, because the width of topRightButton can not be determined)
topRightButton Set the top constraint to Superview. (y), leading constraint to topLeftButton (will be used for x), Set trailing constraint to superview. Now the width of both buttons can be determined, because we have an external startX + endX and we know the two buttons touches each other and are equal widths. Thus the available space will be split to get the width of the two buttons.
I have a ImageView whose top constraint is 80 and center. I have two textView with margin of 100 from top consecutive object and 100 margin from both left and right.
When I am trying to implement auto-layout i am not able to do so because of many warning as shown in the figure :-
your imageview and textviews are not comfortable with your current constraints .if you add top and centre constraints for uiimageview you must add the height and width constraints for accessing the x value.
and also you just add height constraints for both of your textviews and try again. thankyou
Every time when you give constraint do following things :-
Fix the width and height of the element.
Give one vertical constraint and one horizontal constraint.
Don't do over-constraint.
Update it where it is showing warning.
If you set Left/Right margin and CenterX, your system is over-constraint.
You should set : Left + Center or Right+Center or Left+Right.
Next you should change the content Hugging and Compression priority.
I'm currently setting up a login screen that should ultimately look something like this:
I've successfully accomplished all the constraints needed to create the desired look on all screen sizes, however, I can not seem to figure out the constraint needed to correctly align the "Don't have an account? Signup". I've designed it so the "Don't have an account?" is a UILabel, and "Signup" is a UIButton. I've just aligned these side by side.
The UILabel, "Don't have an account?", has the following constraints:
The UIButton, "Signup, has the following constraints:
These constraints seem to accomplish what they need to on screen sizes 4" and below. however the 4.7 inch, and 5.5 inch (iPads excluded), have wide spacing between the UILabel and UIButton. I've read Ray Wenderlich's tutorial on auto layout, and still can not figure out the problem (I'm new to auto layout, but I have an idea what I'm doing. I'm not just adding random constraints hoping it works).
This is what it looks like on all my targeted devices:
Notice as screen size increases, so does the gap in between the label and button. Any help is appreciated.
You are setting the leading space of the label to its superview, and you are setting the trailing space of the button to its superview. So obviously if the superview gets wider, they are going to get further apart.
So if that's not what you want, don't do that.
The actual solution to what you want to do is quite tricky. You want these two objects to behave as a group, and you want that group to be centered. There's no simple way to express that. You will need to make a group. In other words, you will need a container view, give that view an absolute width and center it, and put these two objects inside the container.
New in iOS 9, a UIStackView can help you with this.
Another approach that works is to use a couple UIViews as spacers. I sometimes prefer this to containment, but it is probably a matter of taste.
Remove the leading constraint from your UILabel.
Remove the trailing constraint from your UIButton.
Add a UIView with clear background in front of your UILabel. Set a leading constraint from this UIView to the container leading edge with constant 0. Set a trailing constraint to the UILabel with constant 0.
Similarly, add another UIView after your UIButton. Set a leading constraint from this UIView to the UIButton with constant 0. Set a trailing constraint from this UIView to the container trailing edge with constant 0.
Both UIViews will need a Y position and height. These are somewhat arbitrary so I would set Align Center-Y constraints with your UILabel, and height constraints of say 5.
Here's where the magic happens: select both UIViews and set an Equal Widths constraint. This forces the UIViews to occupy equal space on both sides.
UIStackView is overkill for this situation. Just
Put the label and button in a single UIView.
Constrain the label's left and center Y to the container view.
Constrain the button's right and center Y to the container view.
Constrain the label's right edge to the button's left edge.
Set the horizontal content hugging priority of the containing view to 1000.
Constrain the containing view's center X to its superview.
You can do it to your existing code only by setting few constraints. And this would work on all resolutions even on the iPad. You don't need to group them , i have attached the images to show the constraints that i have applied.
And for the button set this constraints
It would be shown properly on all the devices kindly have look as to how it looks on all the resolutions and also in the landscape mode of each resolution
Thanks
Omkar