I want to build an application that takes data from one screen and lists them on another screen. I use TinyDB to do this. My problem is how to delete a tag?
When I choose what to delete, it deletes it but if I get back to the screen from the beginning it shows the entire list without changes.
I attach my blocks here.
Your blocks look fine, your issue seems to be in the other screen...
In the other screen first read your tags from TinyDB again before displaying them... in case this does not help, you might want to edit your question and add a screenshot of the other screen, where it shows the entire list without changes...
Also: never use the open another screen block together with Screen1. Why? see here:
The recommended method of switching screens in App Inventor
Note: there is only one TinyDB, see also the documentation
Each app has its own data store. There is only one data store per app.
Even if you have multiple TinyDB components, they will use the same
data store. To get the effect of separate stores, use different keys.
You cannot use the TinyDB to pass data between two different apps on
the phone, although you can use the TinyDB to share data between the
different screens of a multi-screen app.
A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook http://www.appinventor.org/book2 ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
There is a free programming course here http://www.appinventor.org/content/CourseInABox/Intro and the aia files for the projects in the book are here: http://www.appinventor.org/bookFiles
How to do a lot of basic things with App Inventor are described here: http://www.appinventor.org/content/howDoYou/eventHandling .
Also do the tutorials http://appinventor.mit.edu/explore/ai2/tutorials.html to learn the basics of App Inventor, then try something and follow the Top 5 Tips: How to learn App Inventor
Related
I am following a tutorial video on how to allow users to edit their profile. In this tutorial, they are using storyboards and I am not. I was wondering, do I have to use storyboards in order to follow along? Or can I use their code to plug into mine without the storyboard?
According to Apple documentation:
A storyboard is a visual representation of the user interface of an
iOS application, showing screens of content and the connections
between those screens. A storyboard is composed of a sequence of
scenes, each of which represents a view controller and its views;
scenes are connected by segue objects, which represent a transition
between two view controllers.
As you are probably guessing, storyboards contain information about widgets, animations, views that are required by the code you will be adding to yours. Additionally, Storyboards also contain the connection between the visual elements and the code (outlets and actions). All of that can be created programmatically but the code you will be pasting from this tutorial, if it's coming from a project that includes storyboards, won't contain this associated logic.
So, at this point, it would seem highly unwise to add complexity to your tutorial to recreate these elements at once. What I would suggest is for you to follow the tutorial and then try to remove some of these elements and replace them by code to obtain similar results just as an exercise to learn. Keep in mind that Storyboards have been around to simplify the design of UI in the application, so I would recommend for you to master their usage instead of shying away from them.
Currently I am trying to build such customization of product in Bigcommerce Storefront that allows to display image with dynamic text, which was entered in Textbox. That means product image preview should be shown INSTANTLY with new image with written text.
so that the end user will know how the final product will looks like and also same image should go in shopping cart as well.
I know that there is an app on Shopify named as Product Builder.
Is this possible to do it on Bigcommerce?
Thanks in Advance
It's definitely possible with some fairly advanced client-side code. Unfortunately I don't know of any plug and play systems or apps for Bigcommerce that will achieve what you're looking for, but there are a couple ways to get a live updating product preview if you're willing to get your hands dirty.
Here's an example from my site. Click the button under "personalize this item", and you'll see a live preview image like you describe in the modal. Enter some text and change the monogram style and color, the preview image should update pretty quickly every time you change an option. A solution exactly like mine may not be feasible for you, since that site is using a pretty complex React/Redux implementation built on an extensively customized Stencil theme... it's far from a turnkey solution. That said, you could implement something similar without needing a totally custom app.
The image preview itself in the example above is powered by IMGIX.com. They offer a great service at a fantastic price. Basically my system translates the user-selected Bigcommerce option into a URL string per IMGIX's URL-based API. Displaying the live preview is then as simple as changing the image's src attribute to the corresponding IMGIX URL on every input change. I do this in a React component that consumes a Redux store, but something similar could definitely be done in the framework of your choice, or plain old vanilla JavaScript. Cloudinary offers a similar (maybe even a little bigger) feature set to IMGIX, but I found IMGIX to be a bit faster, and the pricing was considerably less for my usage.
You could also write something that uses the HTML5 canvas to overlay text and effects on an image, and thereby avoid using a third-party service. I found such a solution to be way more work and way more taxing on the client-side device, but it'd definitely be another way to skin the proverbial cat.
There may be other viable solutions out there, but the above has been my experience in implementing something similar to what you're looking for on Bigcommerce. I hope this is helpful!
I have my page1.cs that loads 400 labels in a stacklayout which takes several seconds and am in need of a way to indicate that it is busy loading. I will most likely have other pages in my app that need the same ability.Please suggest a code for it keeping in mind I am a newbie.
You could use ACR User Dialogs. This allows you to display a loading dialog from anywhere in the application. There are plenty of examples on the GitHub repository for it as well. This blocks user input if you want, and has other types of dialogs as well, although I have only used the Loading Dialogs. The basic usage is just like this
UserDialogs.Instance.ShowLoading("Loading...");
and
UserDialogs.Instance.HideLoading();
If you want to do it for a task there is slightly different usage, but is provided in his samples. I currently am using this on Android and iOS and can assure you that they have a clean look.
Forms has a built in ActivityIndicator you can use
I'll start off by saying I am an absolute beginner. I've been following a very good tutorial on YouTube and reading a few books. So far, I have a working app which consists of a splash screen, load up music and then a menu with 6 buttons. I have got these six buttons opening up a new view. I have created a new Java class and a new layout.xml for each new view. Is this right? Basically, all I want to know is how to make an efficient app which allows me to use my 6 buttons to take me to another set of buttons as a sub-menu and then inside those buttons I want to display the information using text and videos and audio. It's a tutorial app. Once I know how to do this then I should be able to continue developing within the app. Any help or ideas please? Since my app is already so large, I'm guessing I've done something wrong, but as I say, the app is working at least.
I had a similar problem. My app was 40MB. I found out my music files were too big. I was using wav files. When I converted them to ogg files, my app went down to 14MB.
This website was useful: http://media.io
The buttons and extra activities probably don't take up that much space. I'm guessing it's the music and maybe any images that you have.
As the title suggests...
Is it possible to add custom Data Detectors to Cocoa apps?
If so, a gentle nudge in the right direction would be great.
Note: To be clear. I want to add new detectors to currents apps. I am not writing a new app.
Thankyou
W
It's not even possible to build a custom data detector on anything but iOS 4. NSDataDetector is only available on iOS 4 and above.
If they existed on OS X and were a plug-in class like Spotlight importers, that'd be a nice feature. Perhaps filing a request at bugreport.apple.com would help it along?
Later update
I think the reason this hasn't been opened up with an API is because they're only meant to find common data (contact info, dates, URLs) for which there is only one (or just a few) uses. That is, contact info can be stored or used in "the" system-designated app. URLs can be auto-highlighted so they're linkable (clicks invoke the system-designated handler - Safari, an app registered to a protocol, etc.). But there's only one direction to funnel those actions and the endpoint is always a major "convenience app" meant to manage this common information (contacts, calendar, browser, email app, phone app...)
On the other hand, consider app-specific information. Data formatted a certain way for use with one app or platform might mean something else entirely to another application. In fact, this is rather common. So what happens when a string like %%SOMESTRING%% is detected? To one app, it might be a placeholder token. To another, it might be a user name. To another still, it might be interpreted as %%USERNAME followed by %%. Suddenly the simple system-wide UI for handling basic data types has to account for multiple actions and/or multiple "data detector plugins" claiming all or part of a format.
I'm not sure we'll ever see custom data detector APIs on iOS or Mac for this reason alone.
While custom data detectors aren't available at the OS level, there is a mechanism that will get you almost there. One possibility is to create a Workflow in Automator and save it in the Services menu.
It can be configured to be active when text is highlighted. You'd either go to the current app's main menu and select the Workflow under "Services", or else right click on the text and go to the "Services" menu from there. Not as easy as clicking on the text as you would a URL, but pretty close.
Create a workflow in Automator on Mac