Touch gestures like tapping, swiping vertically/horizontally, panning, etc. occurs when a user places one or more fingers on the screen and by the time the last finger looses contact, the entire pattern of finger movements is interpreted as a particular gesture by your android application. First all the relevant data of touch events are gathered and then they’re interpreted to see which gestures they match and the pertaining actions are executed as specified in the code.
Tag: mobile
Detecting Common Gestures on Android Using GestureDetector
Gestures are those subtle motions to trigger interactions between the touch screen and the user. It lasts for the time between the first touch on the screen to the point when the last finger leaves the surface. We’re all familiar with it as it’s the most common way to communicate with apps on our mobiles, tablets, etc. these days. Some examples are scrolling in an app by swiping vertically/horizontally, pinch to zoom, long press to select and so on.
Continue reading “Detecting Common Gestures on Android Using GestureDetector”
Quick Tip: Android Convert byte[] Data to ImageView
Let’s say you have a byte[] array of image data that you want to convert into an Image by showing up in an ImageView in your layout. We can achieve that with a few lines of code.
Continue reading “Quick Tip: Android Convert byte[] Data to ImageView”
QuickTip: Store Undefined and Null in Class/Table Rows on Parse.com
Update: Parse is shutting down. So you should start migrating.
I’ve been working on an Android app backed by Parse.com to make my development process faster and easier. So while coding the app I made a decision to have 2 classes (tables) called Conversations and User (exists by default). Conversations has a field called userId that should essentially store the objectId from User class. But some conversations are created by guest so for those records I decided to store NULL or “nothing” (undefined) under the userId column rather than Pointers which is what the column type is.
Continue reading “QuickTip: Store Undefined and Null in Class/Table Rows on Parse.com”
Understanding GridView in Android with Custom Adapters by Building an Image Gallery
GridView is a ViewGroup just like ListView that allows us to display items in a two-dimensional scrolling grid. Just like a ListView the data into a GridView is populated by an Adapter (ListAdapter) that fetches data from various sources like an array or a database. It’s mostly used to build image, video, audio galleries.
Android Realtime (Instant) Search with Filter Class and Filterable Interface Using Custom and Inbuilt Adapter
Android has an excellent Fitler class that helps us filter data from an entire data set based on some pattern (for example a string) provided. Filters are usually created by classes implementing the Filterable interface. It makes sense to use filters (implement the Filterable interface) mostly with adapters, which means Filterable classes are usually Adapter implementations.
Adding Search Functionality to Your Android Application Activity with SearchView and Search Dialog
If you’re building an android application, then most likely you’ll need to implement a search in it to let the user search through a set of data that could be emails, messages, chats, photos, files, etc. Android provides us with a search widget called SearchView that provides a user interface for the user to enter a search query and submit the request. The preferred way to use this widget to provide search in our application is to use it in the action bar.