Android Tip: Display animation in notification RemoteViews

In the Android Notification display, we usually display some static elements, even if we use a custom layout, becauseRemoteViews has many limitations, such as only those basic controls are used. Controls and interface updates must also pass the various set methods provided by RemoteViews. But sometimes, we just want to display animation, because animation can provide better visual effects. Then this article provides two simpler methods.

(For code examples, see: https://gitee.com/spectre1225/notification-anim-demo)

Method 1: Use ViewFlipper to achieve frame-by-frame animation effects

The first method is to use the controls supported by RemoteViews with multiple to display in a loop to achieve a similar The effect of frame-by-frame animation. The corresponding content in the custom notification layout is:ViewFlipperImageView

<ViewFlipper
    android:layout_width="40dp"
    android:layout_height="40dp"
    android:layout_gravity="end|center_vertical"
    android:autoStart="true"
    android:flipInterval="90">

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim0" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim15" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim28" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim43" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim57" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim71" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim85" />

    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:src="@drawable/stat_sys_battery_charge_anim100" />
</ViewFlipper>

No additional settings are required in Java code. Note that ViewFlipper must be set to android:autoStart="true" so that the animation will play automatically.

• Advantages: All versions of the system have good compatibility and can be used.
• Disadvantages: There are too many ImageViews and a lot of code, making modification and replacement troublesome.

Method 2: Use AnimatedImageDrawable to display GIF animation

A new Drawable is introduced in Android 9.0 to display GIF images: AnimatedImageDrawable, and the corresponding xml tag is <animated-image>. In this way, we can Directly place a GIF imageic_test_gif.gif into the drawable directory, and then create a new oneic_anim_gif.xml to reference:

<?xml version="1.0" encoding="utf-8"?>
<animated-image xmlns:android="http://schemas.android.com/apk/res/android"
    android:autoStart="true"
    android:autoMirrored="true"
    android:src="@drawable/ic_test_gif" />

Write directly in the custom notification layout:

<ImageView
    android:id="@+id/iv_logo"
    android:layout_width="40dp"
    android:layout_height="40dp"
    android:src="@drawable/ic_anim_gif" />

HereImageView'ssrc does not directly quote the gif image because it needs to use animated-image's< a i=4> attribute, after all, cannot directly take out the drawable of . autoStartRemoteViewsImageView

Considering system version compatibility, you can choose to set animation resources toImageView in the code:

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
    
    
    remoteViews.setImageViewResource(R.id.iv_logo, R.drawable.ic_anim_gif);
}

The advantages and disadvantages of this method are as follows:

• Advantages: Few resources, one gif, only one xml ofanimated-image, and the replacement is simple.
• Disadvantages: It can only be used on Android 9.0 and above systems.