BigImageViewer

Big image viewer supporting pan and zoom, with very little memory usage and full featured image loading choices. Powered by Subsampling Scale Image View, Fresco, Glide, and Picasso.

Demo

Usage

Dependency

allprojects {
    repositories {
        maven {
            url  "http://dl.bintray.com/piasy/maven"
        }
    }
}

compile 'com.github.piasy:BigImageViewer:1.2.9'

// load with fresco
compile 'com.github.piasy:FrescoImageLoader:1.2.9'

// load with glide
compile 'com.github.piasy:GlideImageLoader:1.2.9'

// progress pie indicator
compile 'com.github.piasy:ProgressPieIndicator:1.2.9'

initialize

// MUST use app context to avoid memory leak!
// load with fresco
BigImageViewer.initialize(FrescoImageLoader.with(appContext));

// or load with glide
BigImageViewer.initialize(GlideImageLoader.with(appContext));

Note that if you've already used Fresco in your project, please change Fresco.initialize into BigImageViewer.initialize.

Layout

<com.github.piasy.biv.view.BigImageView
        android:id="@+id/mBigImage"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:optimizeDisplay="false"
        />

You can disable display optimization using optimizeDisplay attribute, or BigImageView.setOptimizeDisplay(false). Which will disable animation for long image, and the switch between thumbnail and origin image.

Java

BigImageView bigImageView = (BigImageView) findViewById(R.id.mBigImage);
bigImageView.showImage(Uri.parse(url));

// you can show thumbnail before the big image is loaded
bigImageView.showImage(Uri.parse(thumbnail), Uri.parse(url));

Downloading progress

bigImageView.setProgressIndicator(new ProgressPieIndicator());

There is one built-in indicator, ProgressPieIndicator, you can implement your own indicator easily, learn by example.

Prefetch

You can prefetch images in advance, so it could be shown immediately when user want to see it.

BigImageViewer.prefetch(uris);

Save image into gallery

bigImageView.setImageSaveCallback(new ImageSaveCallback() {
    @Override
    public void onSuccess(String uri) {
        Toast.makeText(LongImageActivity.this,
                "Success",
                Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onFail(Throwable t) {
        t.printStackTrace();
        Toast.makeText(LongImageActivity.this,
                "Fail",
                Toast.LENGTH_SHORT).show();
    }
});

bigImageView.saveImageIntoGallery();

Get current image file

String path = bigImageView.currentImageFile(); // only valid when image file is downloaded.

Init scale type

<com.github.piasy.biv.view.BigImageView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:initScaleType="centerInside"
        />

mBigImageView.setInitScaleType(BigImageView.INIT_SCALE_TYPE_CENTER_CROP);

value	effect
centerInside	default, Scale the image so that both dimensions of the image will be equal to or less than the corresponding dimension of the view. The image is then centered in the view. This is the default behaviour and best for galleries.
centerCrop	Scale the image uniformly so that both dimensions of the image will be equal to or larger than the corresponding dimension of the view. The image is then centered in the view.
auto	determine the max scale and min scale by image size and view size, fit the image to screen and centered when loaded.

Full customization

You can get the SSIV instance through the method below:

public SubsamplingScaleImageView getSSIV() {
    return mImageView;
}

Then you can do anything you can imagine about SSIV :)

You can try the example to checkout the differences! https://fir.im/BIV . Thanks for fir.im!

Caveats

Handle permission when you want to save image into gallery.
When you want load local image file, you can create the Uri via Uri.fromFile, but the path will be url encoded, and may cause the image loader fail to load it, consider using Uri.parse("file://" + file.getAbsolutePath()).

Why another big image viewer?

There are several big image viewer libraries, PhotoDraweeView, FrescoImageViewer, and Subsampling Scale Image View.

They both support pan and zoom. PhotoDraweeView and FrescoImageViewer both use Fresco to load image, which will cause extremely large memory usage when showing big images. Subsampling Scale Image View uses very little memory, but it can only show local image file.

This library show big image with Subsampling Scale Image View, so it only uses very little memory. And this library support using different image load libraries, so it's full featured!

If you are interested in how does this library work, you can refer to this issue, and Subsampling Scale Image View.

Performance

Memory usage of different libraries:

-	PhotoDraweeView	FrescoImageViewer	BigImageViewer
4135*5134	80MB	80MB	2~20 MB

Todo

Those features are offered by image load libraries, and they should be easy to implement, but I don't have enough time currently. So your contributions are welcome!

wanghaihui / BigImageViewer