Added grow animation to LrcView

app/src/main/java/code/name/monkey/retromusic/lyrics/CoverLrcView.kt

@@ -167,7 +167,7 @@ class CoverLrcView @JvmOverloads constructor(
                         isShowTimeline = false
                         removeCallbacks(hideTimelineRunnable)
                         mCurrentLine = centerLine
-                        invalidate()
+                        animateCurrentTextSize()
                         return true
                     }
                 } else {
@@ -458,6 +458,7 @@ class CoverLrcView @JvmOverloads constructor(
                 mCurrentLine = line
                 if (!isShowTimeline) {
                     smoothScrollTo(line)
+                    animateCurrentTextSize()
                 } else {
                     invalidate()
                 }
@@ -536,6 +537,18 @@ class CoverLrcView @JvmOverloads constructor(
         canvas.restore()
     }
 
+    fun animateCurrentTextSize() {
+        val currentTextSize = mCurrentTextSize
+        ValueAnimator.ofFloat(mNormalTextSize, currentTextSize).apply {
+            addUpdateListener {
+                mCurrentTextSize = it.animatedValue as Float
+                invalidate()
+            }
+            duration = 300L
+            start()
+        }
+    }
+
     @SuppressLint("ClickableViewAccessibility")
     override fun onTouchEvent(event: MotionEvent): Boolean {
         if (event.action == MotionEvent.ACTION_UP
@@ -613,7 +626,7 @@ class CoverLrcView @JvmOverloads constructor(
     private fun adjustCenter() {
         smoothScrollTo(centerLine, ADJUST_DURATION)
     }
-    /** 滚动到某一行  */
+
     /** 滚动到某一行  */
     private fun smoothScrollTo(line: Int, duration: Long = mAnimationDuration) {
         val offset = getOffset(line)