I'm trying to do this animation in flutter :
https://material.io/guidelines/motion/choreography.html#choreography-creation
My problem is that I have absolutely no idea how to do that.
As far as I know, widgets in flutter don't know their position nor the position or other widgets at all.
And you can't access context.size inside the build method.
I tried to use Hero animation to do it. Or ScaleTransition. But it's definitely not working.
You can use showMenu to dynamically show a popup menu at a given location. Consider using PopupMenuButton, which is an IconButton that automatically shows a menu when it is tapped. There's an example in the Gallery. If showMenu doesn't do what you want, you can copy the code in popup_menu.dart and customize it to make your own version. It uses CustomSingleChildLayout and PopupRoute.
If you just want to absolutely position a Material or Card on top of other elements, you can give it some elevation and use a Positioned within a Stack. You can use an AnimatedSize to adjust the element's size with a Curve. This won't interact with the back button on Android automatically, so if you want that, you may have to use addLocalHistoryEntry or PopupRoute.
If I understand you correct - you want to show square widget, and animation is not suitable at most because widget doesn't know its size.
In this case you can try MediaQuery.of(context).size.width - it returns width of your screen, so you can use it for calculating widgets size
Related
I am using Unity 5 and I started to make a menu scene. When I made the canvas, all of values under the Rect Transform component are locked and it says "some values driven by Canvas." The only thing I can change is the z position when using the gizmo in the editor. I can't reset the position or anything. Why is this happening?
This means that the canvas's canvas component has it's render mode set to Screen space - overlay. This forces it to be the size of the screen. Change it to World Space and it will allow you to resize it and move it around.
Changing the Render mode is not an ideal solution; neither is Overlay mode the reason why this is happening at all. World Space is just a render mode that changes the way your whole UI behaves and would mean a whole different set up and a whole lot more work just to get a child UI object to move independently.
Here is the description of what World Space is for from the Unity site:
In this render mode, the Canvas will behave as any other object in the
scene. The size of the Canvas can be set manually using its Rect
Transform, and UI elements will render in front of or behind other
objects in the scene based on 3D placement. This is useful for UIs
that are meant to be a part of the world. This is also known as a
“diegetic interface”.
The Rect Transform usually gets locked because it is a child of another Canvas Object which controls its Transforms. The way to fix this is to overwrite it by adding a “Layout Element” component to it. From there you can configure it to work the way you like and it can have transforms independent of the Parent UI Object.
For full details, see this Unity support page: https://support.unity3d.com/hc/en-us/articles/115000179163-How-to-overwrite-Width-and-Height-values-that-are-driven-by-a-Layout-Group-in-runtime-
Canvas is depend on game tab in your window panel.
Adjust panel by use of close tab or resize panel or doc game panel.
It will help you make default 800 X 600 canvas.
I have just upgraded Unity to version 4.6 and tried to create a button by Create -> UI -> Button.
However, this button doesn't show up in #Screen tab but it does in Game tab.
Please look at the screen shoot below:
Another question is: The default width and height when creating a new button is 160 x 30. When I change the source image with my own image button, I have to change the width and height parameters in rect transform. Is there any faster way to automatically obtain new width and height based on the image which I insert?
Thank you very much!
First, double click the button in your hierarchy and see that it indeed does not show in the Scene view, excluding any kind of zoom problem. (By the way, I'm assuming you mean "Scene" and not "Screen", right?) Things in different cameras or canvases might have very different scales but appear correctly in the Game view. I don't know how used you are to Unity, so I'm sorry if this sounds obvious. :)
Next, check the dropdown labeled "Layers" on top of Unity's editor, to the right of the Play, Pause and Step buttons. See if the layer of your button (which in this case is "UI") is visible. It should have an open eye icon next to it.
Regarding your other question, after dragging your sprite to the Image component, you can press the "Set Native Size" button, which will set the size of your object to the dimensions of your Sprite. Regarding the new UI, I think this is as automatic as it gets. Note that "Set Native Size" will only appear if your Image type is set to Simple (probably what you want) or Filled in the component.
I had the same problem before and here's a possible solution.
By default, the editor camera (Scene Tab) renders the World Space,
so your Canvas component's render mode should be set to "World Space".
The problem may only occur when you're trying to (or supposedly) render your UI in Screen Space - Overlay or Screen Space - Camera in the Canvas component.
So if you want to properly edit UI objects in the scene tab/window; set the Canvas component's render mode to World Space.
We don't have this problem in Unity 4.x before because I think Unity automatically renders any render mode from the Canvas component, however, that doesn't happen in Unity 5.x. I'm guessing it's either intentional that they do that or it's a bug on Unity UI feature.
The new Unity 4.6 comes with a new GUI, when I change de resolution on Unity the UI Button scales perfectly but when I test on the Nexus 7 device the Button looks too small. Any idea how to solve this?
Unity's new GUI system uses "anchors" to control how gui elements (like buttons) scale in relation to their parent container.
Unity has a tutorial video on how to use the new "Rect Transform" component (where the anchors are configured) here: http://unity3d.com/learn/tutorials/modules/beginner/ui/rect-transform.
The last half of the tutorial is all about anchors. That page has links to the entire tutorial series. It's not too long. You should watch the whole thing.
Specific to your question:
The anchors are visible in your first screen shot. They are those 4 little arrows at the top left of your button.
Right now, your button is only anchored by it's top left corner.
The two right anchors need to be dragged to the right so that the right edge of your button is anchored to a space inside its parent container.
Depending on your situation, the two bottom arrows may need to be dragged down so that the bottom edge of your button is anchored as well.
The video I linked above covers all this in detail.
Lastly, for the font size to scale nicely on different resolutions, you will need to add and configure a reference resolution component to the base canvas of your UI, as Ash-Bash32 wrote earlier.
Update: The best way to add a Reference Resolution component is through the inspector window for the base canvas in your UI.
1) click the "Add Component Button" at the bottom of the inspector.
2) type the word "Reference" in the search filter field.
3) select the "Reference Resolution" component in the search results.
The Reference Resolution is now renamed as Canvas Scaler.. Along with the renaming they have added many more features for the dynamicity of the Canvas. You can go through the Unity Doc of Canvas Scaler and also take a look at this article for a practical example of how and why to use Canvas Scaler. Also make sure you use the Anchor Points to good effect to make this more robust...
To Scale UI added the ReferenceResolution Component to the Canvas you want to scale.
P.S. Theres no Documention for ReferenceResolution
If you want the button to be the same size for all screens and resolutions, you have to add the canvas scaler component to the canvas and the set the screen match mode to: match width or height, here is the link to the docs, this helps a lot if you want to aim to different sizes or resolutions:
http://docs.unity3d.com/Manual/HOWTO-UIMultiResolution.html
This becomes giant and convoluted once you start laying things out in code AND using a canvas scaler, so I wish to provide a thorough answer to save someone the hours I went through.
First, don't use anchoredPosition to position anything, unless you fully realize it is a 0.0 to 1.0 number. Use the RectTransform localPosition to do the actual laying out, and remember it's in relation to the parent anchor. (I had to lay out a grid from the center)
Second, put a canvas scaler on the parent layout object AND the inner ui pieces. One makes the layout in the right position, the other will resize your elements so they actually show up right. You can't rely on the the parent unless the children also have scalers (and Graphic Raycasters to touch them).
Third, if you have a scaler, DON'T use Screen.width and height, instead assume the screen is the same value you put for the scalers (hopefully you used the same, or know what you're doing). The screen width always returns the actual device pixels, retina devices too, but the canvas scalers DO NOT account for this. This probably gives unity the one remaining way to find actual screen dpi if your game wants it. Edit: This paragraph applies to any parent canvas connected to the code doing your laying out. Not stray canvases, you can probably mix it up. Just remember unity's guidelines on performance with canvases.
Fourth, the canvas is still a bit buggy. Even with the above working, some things don't render until you delete and recreate a canvas, if you re-open the scene or it crashes. Otherwise, the above is the general "rules" I've found.
To center a "grid of things" you can't just use half of the canvas scaler's width or height, you have to calculate the height of your grid and set the offset by half of it, otherwise it will always be slightly off. I just added this as an extra tip. This calculation works for all orientations.
I want to build a custom control that would work like this:
You have a kind of NSButton with an image.
You click the button and than appears a big square with a grid of photos.
You click one of the photos and it is set up as new image for the button. (square dissapears)
Now, how to draw this big square with photos if I want it not to be limited to window frame?
I mean, if the button was close to window border the square is going to be partially outside window. I would also like to add some shadow to the square and an animation for opening/closing.
One important thing: I want to be able to draw not only a square but any other simple shape (circle)!
This isn't really a drawing question so much as a general custom views question. It's important to make that distinction.
I'll describe this in terms of rectangles to give you the general idea*. You should make sure you understand the view hierarchy and view geometry in Cocoa. Without this important requisite knowledge, you'll remain dead in the water.
It's easy to set an NSButton's image, so I'll leave that to you. Your button's action, however, would tell some controller to show the "image picker" for the given button. Your image picker would be some type of borderless window with an image list inside. The image picker could be an IKImageBrowserView (you'll have to enable Image Kit in Interface Builder for this control to appear), which gives you an iPhoto-like grid of images (with/without titles, different border types, etc.).
An explanation of the operation of this controller and how it creates the window, manages the selection, and sets the button's image is very broad so if you get hung up on any of those steps, you'll need to create a separate question for each problem, otherwise this answer would have to be an instruction manual for writing your app for you.
* Your problem is a little more difficult because of your desire to have differently-shaped "popup windows" ... you'd have to make sure your available photos fit neatly within the shape so none of them are cut off. Armed with the basic knowledge of view geometry, I'll leave this to you as an exercise. A hint: you can use a borderless, transparent window to host a view that draws itself in any shape you please.
I've been banging my head about this seemingly easy task and I could really use some help.
I have a wide Image loaded in the gui (using the designer..) and I want to be able to draw only a portion of it, a rectangle.
I need to be able to change this rectangle position over the large image, in order to draw a different part of the larger image at will. In this process the rect must maintain its size.
Using the Ui::MainWindow object I'm able to access the label holding the image and a solution that involves using this option is preferred (in order to keep up with the rest of the code I've already written )
Any solution will be much appreciated :)
Thanks,
Itamar
I would definitely (for ease of use) just place an empty label as placeholder in Designer.
Then implement the paintEvent for this label (delegate it to your own method). You'll have also have to look into QPainter, QPixMap, etc... Should be doable based on these hints and the documentation.
If you want more, I suggest you provide a small code snippet to work upon.
If you want to do this more or less purely through designer, you could put a QScrollArea where you want the portion of the image to appear. If you set the scroll area's scrollbar policy to be never shown, you can then manually change what part is visible via the scroll area widget. However, this would probably be more complex that creating a derived widget and reimplementing the paint function.