[android] パルスアニメーション

gistfile1.txt

    // アニメーション
    <?xml version="1.0" encoding="utf-8"?>
    <set xmlns:android="http://schemas.android.com/apk/res/android"
      android:interpolator="@android:anim/accelerate_interpolator">
      <alpha
        android:duration="500"
        android:repeatCount="-1"
        android:repeatMode="restart"
        android:fromAlpha="0.8"
        android:toAlpha="0.0" />
      <scale
        android:duration="500"
        android:repeatCount="-1"
        android:repeatMode="restart"
        android:fromXScale="1.0"
        android:fromYScale="1.0"
        android:pivotX="50%"
        android:pivotY="50%"
        android:toXScale="2.0"
        android:toYScale="2.0" />
    </set>

    // パルスイメージ
    <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="oval">
        <size
            android:width="48dp"
            android:height="48dp" />
        <solid android:color="@color/colorAccent" />
    </shape>

    // レイアウト
    <FrameLayout
        android:layout_width="96dp"
        android:layout_height="96dp"
        app:layout_anchor="@id/main"
        app:layout_anchorGravity="bottom|right|end">

        <ImageView
            android:id="@+id/image_anim_fab"
            android:layout_width="48dp"
            android:layout_height="48dp"
            android:layout_gravity="center"
            android:background="@drawable/image_pulse" />

        <android.support.design.widget.FloatingActionButton
            android:id="@+id/fab_measure"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@drawable/ic_fab_measure"
            app:fabSize="normal" />
    </FrameLayout>
    
    // コード
    private Animation mPulseAnimation;
    private ImageView mPulseImage;
    private boolean mPulseStarted = false;
    
    mPulseImage = (ImageView) findViewById(R.id.image_anim_fab);
    mPulseAnimation = AnimationUtils.loadAnimation(
                getActivity().getApplicationContext(), R.anim.pulse);
                
    private void togglePulseAnimation() {
        if (!mPulseStarted) {
            startPulseAnimation();
        } else {
            stopPulseAnimation();
        }
    }

    private void startPulseIfNeeded() {
        MainActivity activity = (MainActivity) getActivity();
        if (activity.isServiceStarted()) {
            startPulseAnimation();
        }
    }

    private void startPulseAnimation() {
        if (mPulseImage != null && mPulseAnimation != null) {
            mPulseImage.startAnimation(mPulseAnimation);
            mPulseStarted = true;
        }
    }

    private void stopPulseAnimation() {
        if (mPulseImage != null && mPulseAnimation != null) {
            mPulseImage.clearAnimation();
            mPulseStarted = false;
        }
    }