Google地图Marker添加时默认图标短暂显示问题求助

方案1：提前设置透明占位图标 #

添加Marker前，直接给MarkerOptions设置完全透明的占位图标，从根源避免默认图标被渲染：

// 生成1x1的透明Bitmap作为占位
private fun getTransparentPlaceholder(): Bitmap {
    return Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888).apply {
        eraseColor(Color.TRANSPARENT)
    }
}

// 添加Marker时先设置占位图标
val markerOptions = MarkerOptions()
    .position(targetLatLng)
    .icon(BitmapDescriptorFactory.fromBitmap(getTransparentPlaceholder()))
val m = mMap?.addMarker(markerOptions)
// 再执行自定义图标和动画逻辑
setIconToMarkerWithAnimation(m, yourCustomBitmap)

方案2：调整动画时序，先隐藏再显式 #

修改动画逻辑，先将Marker设为完全透明，再设置自定义图标，最后执行渐显动画，确保默认图标没有显示机会：

private fun setIconToMarkerWithAnimation(m: Marker?, bitmap: Bitmap? = null) {
    val mapIcon = bitmap ?: getBitmapFromMarker(m)
    // 先将Marker设为完全透明
    m?.alpha = 0.0F
    // 设置自定义图标
    m?.setIcon(mapIcon?.let { BitmapDescriptorFactory.fromBitmap(it) })
    // 从0到1执行渐显动画
    val animation = ValueAnimator.ofFloat(0.0F, 1.0F)
    animation.duration = MapConstants.DEFAULT_ANIMATION_DURATION
    animation.interpolator = AnticipateOvershootInterpolator()
    animation.addUpdateListener { animationState ->
        val alpha = animationState.animatedValue as Float
        m?.alpha = alpha
    }
    // 加10ms延迟，确保图标加载完成后再启动动画
    animation.startDelay = 10
    animation.start()
}

方案3：预加载自定义图标Bitmap #

如果自定义图标是从View生成的，提前在页面初始化阶段预生成所有需要的Bitmap，避免添加Marker时才生成导致的延迟，让setIcon能即时执行：

private val preloadedMarkerBitmaps = mutableMapOf<String, Bitmap>()

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    // 预加载所有类型的Marker图标
    preloadedMarkerBitmaps["shop"] = generateMarkerBitmap(R.layout.marker_shop)
    preloadedMarkerBitmaps["park"] = generateMarkerBitmap(R.layout.marker_park)
}

// 将布局转为Bitmap
private fun generateMarkerBitmap(layoutId: Int): Bitmap {
    val view = LayoutInflater.from(this).inflate(layoutId, null)
    view.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED)
    view.layout(0, 0, view.measuredWidth, view.measuredHeight)
    return Bitmap.createBitmap(view.measuredWidth, view.measuredHeight, Bitmap.Config.ARGB_8888).apply {
        val canvas = Canvas(this)
        view.draw(canvas)
    }
}

// 添加Marker时直接使用预加载的Bitmap
val targetBitmap = preloadedMarkerBitmaps["shop"]
val m = mMap?.addMarker(MarkerOptions().position(targetLatLng))
setIconToMarkerWithAnimation(m, targetBitmap)

内容的提问来源于stack exchange，提问作者Piyush Maheswari