Barrage

It is a library to create a effect such as below.

Yes, it is a Native Barrage like bilibili.com. You can easily get it.

And, if you want to have a effect of coins' dropping down:

And, if you want a balloons' rising:

The demo is available here.

Installation

gradle

compile 'com.liuzhuang.opensource:barrage:0.0.1'

maven

<dependency>
  <groupId>com.liuzhuang.opensource</groupId>
  <artifactId>barrage</artifactId>
  <version>0.0.1</version>
  <type>pom</type>
</dependency>

Basic usage

In xml(you can also create the view programmatically):

<com.android.liuzhuang.library.ui.BarrageView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_below="@id/start"
    android:id="@+id/barrag

And in code:

Barrage barrage = new Barrage(this, (BarrageView) findViewById(R.id.barrage));

List<BarrageDo> data = new ArrayList<>();
for (int i = 0; i < 50; i++) {
    data.add(new BarrageDo.Builder()
    		// set text
            .setText("text" + i)
            // set text color
            .setTextColor(colors[random.nextInt(10)])
            // set time from now when this item shows.
            .setMillisecondFromStart(1000*random.nextInt(5))
            //set text size
            .setTextSize(50 + random.nextInt(10))
            // set offset from top (LEFT_RIGHT or RIGHT_LEFT direction) or left (TOP_DOWN ow DOWN_TOP direction).
            .setOffsetFromMargin(100 + random.nextInt(1000))
            // set bitmap
            .setImage(balloonBitmap)
            // set bitmap config
            .setImageConfig(new BarrageDo.ImageConfig(size, size, 0, 0))
            // determine rotate the bitmap or not when TOP_DOWN and DOWN_TOP 
            .setRotateImage(false)
            // set velocity of moving
            .setVelocity(random.nextInt(20) + 10)
            // set acceleration
            .setAcceleration(0)
            // set direction
            .setDirection(direction)
            .build());
}
barrage.addDataList(data);
barrage.start();

And the overall usage is MainActivity.java in /app module.

Advantage

Barrage is drawn by SurfaceView in background thread which means the Main Thread won't be affected. And also, you can add data in any thread to Barrage. It is thread-safe.

You should know

I did not focus on Bitmap memory managing. So if you have many large Bitmap in Barrage, it may occurs OutOfMemory Error. The best practice is using a small same bitmap such as my demo's coin or balloon.