Best practice of showing gif in Android

问题:

I tried to load a list of gifs and displays them on listview. Currently, I display each gif into a webview but it's very slow and looks ugly. I did some researches today but nothing could help me.

Do you guys have any great idea that showing gifs smoothly? BTW, I got all gifs from url links.

回答1:

I would recommend utilising a recently open sourced library, released by Facebook, called fresco https://github.com/facebook/fresco. From my experience, it handles GIFs quite nicely by using some fancy caching methods outside of VM heap to avoid staggering effects of GC on bitmaps/images. User guide: http://frescolib.org/docs/getting-started.html#_

Below is just a basic adapter to implement into a listview:

public class FrescoGifAdapter extends BaseAdapter {


    ArrayList<String> urlList;
    private static LayoutInflater inflater=null;

    public FrescoGifAdapter(Activity activity, ArrayList<String> urlList) {

        if(urlList==null) {
            this.urlList = new ArrayList<>();
        }
        else {
            this.urlList = urlList;
        }
        inflater = (LayoutInflater)activity.
                getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    }

    public int getCount() {
        return urlList.size();
    }

    public String getItem(int position) {
        return urlList.get(position);
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {

        View vi = convertView;

        if(convertView==null){
            vi = inflater.inflate(R.layout.fresco_item, null);
            //Load Uri with URL.
            Uri uri = Uri.parse(getItem(position));

            SimpleDraweeView draweeView = (SimpleDraweeView) vi.findViewById(R.id.my_image_view);

            //Controller is required for controller the GIF animation, here I have just set it to autoplay as per the fresco guide.
            DraweeController controller = Fresco.newDraweeControllerBuilder()
                    .setUri(uri)
                    .setAutoPlayAnimations(true)
                    .build();
            //Set the DraweeView controller, and you should be good to go.
            draweeView.setController(controller);

        }

        return vi;
    }

}

fresco_item.xml (You can change dimensions to suit, I just defaulted to guide dimensions). Caveat is scaling has to be handled by fresco. In fact, they advise against setting any custom ImageView attributes as it breaks stuff.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:fresco="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <com.facebook.drawee.view.SimpleDraweeView
        android:id="@+id/my_image_view"
        android:layout_width="130dp"
        android:layout_height="130dp"
        fresco:placeholderImage="@drawable/ic_launcher"
        />


</LinearLayout>

And then in your onCreate:

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //Required by Fresco to be initalized before setContentView.
        Fresco.initialize(this);
        setContentView(R.layout.activity_main);
        ListView lv = (ListView) findViewById(R.id.listview);
        ArrayList<String> urlList = new ArrayList<>();
        //Load neon cats
        for(int i = 0; i < 10; i++) {
            urlList.add("https://media3.giphy.com/media/JLQUx1mbgv2hO/200.gif");
        }

        lv.setAdapter(new FrescoGifAdapter(this, urlList));

    }

回答2:

webview used for gifimage load without any library