Given:
A number of images (10 - 15) residing in assets folder (as practice shows, the better approach is to keep high-resolution images in assets)
Android UI thread (caching drawables in advance is already made in a background thread)
The issue:
Need to display all the images one on another smoothly and not blocking UI thread after the images are drawn.
Already used approaches:
Dynamically create a required number of ImageView and then call .setImageDrawable(). This takes a lot of time but the worst thing is that the UI thread is being blocked even after all the images are drawn on their ImageView.
Create a LayerDrawable object and pass as argument an array of the required Drawables. Then put it on an ImageView also by calling .setImageDrawable(). This option behaves the same like the one described above.
Is there a way to solve this issue? Or Android devices not capable to cope with it?
Try Picasso library:
http://square.github.io/picasso/
It has support for resources:
Picasso.with(context).load(R.drawable.landing_screen).into(imageView1);
Picasso.with(context).load("file:///android_asset/DvpvklR.png").into(imageView2);
Picasso.with(context).load(new File(...)).into(imageView3);
If you are requiring a smooth transition between images, please try viewFlipper
https://developer.android.com/reference/android/widget/ViewFlipper.html
Basically you can add imageView inside the viewflipper and start animation to move from previous to next image. I am not sure if you need user interactions like scrolling or not. You can try viewPager if user need to scroll betweens images.
Please note that Glide does provide some transition effects for switching between placeholder and image to display. But transition between images are not included, you can have a look here
http://bumptech.github.io/glide/doc/transitions.html
I hope this helps because i am not sured that if you are asking the transition between images or rendering images.
Related
I've been trying to create a Recycler View full of Card Views. Currently, I'm using the Recycler View from this tutorial and loading it with 14 different images. The professional quality images range in size from 134K to 242K.(Down from 8MB - 18MB)
I know that the images may be too big but, I feel there must be some way to get better performance while scrolling. Can someone point me in the right direction?
Edit: The images will be stored on the device. There will probably never be more than 20 of them.
You can use Picasso library or Android Universal Image Loader
Picasso
Android-Universal-Image-Loader
You don't need any AsyncTask.Theese 2 library handling image operations in background so you can keep scrolling smoothly. I am using Picasso in my project right now. You can add error drawable , temporary placeholder default drawable , and its so simple automatically caching.
Just use one of them in onBindViewHolder to bind any image to imageView
Load the images in a separate thread (or AsyncTask).
I need some help,
I am creating an app, and want it to run faster I mean when the app is started first it shows a blank white screen for o 1-2 seconds and then loads images. I have a layout background image, and 4 imageviews which are clickable and take you to the next activity. I read somewhere i should use threads to load images and it will load them on a separate thread faster, but i have some problem using it.
So here are the problems and android studio explanations:
Thread thread=new Thread(
public void run(){
ImageView tipka=(ImageView)findViewById(R.id.tipkaproba);
tipka.setImageResource(R.drawable.instructions);
LinearLayout asd=(LinearLayout)findViewById(R.id.layoutproba);
asd.setBackgroundResource(R.drawable.backfround123);
}
).start();
Now the android studio says:
After
"Thread(" )expected
Before
"public void run(){"
; expected
On ").start();"
Invalid method declaration; return type required, Missing method body, or declare abstract.
Now i would like to know:
Does this speed up loading images, ( if not how to do it then)
How to fix my errors.
Thanks anyway !
Do all images fit in the screen?! If users need to scroll to view other images why load all of them at once? Use a grid view with adapter to load the image. In this way when the app start only images on the screen will be loaded and then when the user scrolls other images show up!
another thing you can do is to have 2 version of each image. one low quality with small size that loads first and one for high quality image. that will load latter. You can also calculate the base color for each image (use open source code or do it manually). then set the background image of iamgeview to this color. So when the image finally loads on the screen. The difference is not as dramatic as it was before.
If you want to use thread try AsyncTask first. Using AsyncTask is simpler than defining thread yourself.
Try to decrease the size of your images! If you be able to do this. it works better than any other trick! It's mobile, you don't have to show supper high quality images. users don't even notice most of the time
You probably took care of this but it worth mentioning that you need to provide different images for different screen densities and it's critical for performance as well as quality.
I've a ListView in which each row item contains many ImageViews apart from some content.
That is, there will be many list items, each containing many images.
In order to not to hold user unnecessarily, I'm showing the content first & then downloading the images asynchronously.
Currently, for each image I'm starting a new AsycTask.
Although, it working alright, but this not a good approach.
In place of this, what should I use?
use this library, best in android for image loading..
https://github.com/nostra13/Android-Universal-Image-Loader
Your scenario seems to fit exactly to use LazyLoading of images. This basically loads images in the background and shows them as soon as they're loaded.
You might want to see this:
Lazy load of images in ListView
An alternative would be using a ThreadPoolExecutor with the images to load, but the above works pretty well and is recommended.
Try using the library
http://square.github.io/picasso/
Many common pitfalls of image loading on Android are handled automatically by Picasso:
Handling ImageView recycling and download cancelation in an adapter.
Complex image transformations with minimal memory use.
Automatic memory and disk caching.
i am new to android and i want to set an image as background to different fragments in an activity.But the images are to large that they make my application to increase in memory and i don't want this. The activity have 6 different fragments and each have different background, here i set the background images from drawable.
i referred this.but i didn't get correct solution.
How could i make them so that the memory size of images will be less?
Android - Reduce the memory usage of Bitmap Drawables
On this concrete case you have 2 options:
1 - Set the image as background on the root view of your fragment Layout. Doing that you'll avoid out of emmory errors, but the image will be scalled to fullfill the whole screen, so it could be diformed.
2 - Use Picasso library http://square.github.io/picasso/ to load the file images. It can be helpful to manage memory issues.
Also, the best thing you could do before starting is to reduce the size of the images using some software such as https://tinypng.com/.
Hope it helps
What i am trying to do is toscroll through a list of images. But when i scroll down or up quickly the images are misplaced in order. A diff pic comes in the place where it was supposed to be. I have tried setting the imageview to null drawable from my imageloader library to clear any rpevious images if any. But the issue persists. What should i do
You can try to use Universal image loader
This is for listView optimization and improving performance if your listView contain images from web.
Features:
Multithread image loading Possibility of wide tuning ImageLoader's
configuration (thread executors, downlaoder, decoder, memory and disc
cache, display image options, and others) Possibility of image
caching in memory and/or on device's file sysytem (or SD card)
Possibility to "listen" loading process Possibility to customize
every display image call with separated options Widget support
Finally discovered the culprit. I was using the imageview.bringtofront() function which was causing the problem for some unknown reason. I wanted to put a part of the imageview infront of the other and was using the relative layout & bring to front. Now i removed the bringtofront() and rearranged the imageview in relativelayout so that its already in the front. Resolved. Thank you all