Android避免内存抖动的解决方案

for (i in 0..100000) {  
    val temp = "Item $i" // 每次循环new一个String → 疯狂GC！  
}  

val sb = StringBuilder()  
for (i in 0..100000) {  
    sb.clear()  
    sb.append("Item ").append(i) // 复用StringBuilder  
}  

override fun onDraw(canvas: Canvas) {  
    val paint = Paint() // 每次绘制都new → 内存炸裂！  
    canvas.drawText("Hello", 0f, 0f, paint)  
}  

private val paint = Paint() // 提前初始化  

override fun onDraw(canvas: Canvas) {  
    canvas.drawText("Hello", 0f, 0f, paint)  
}  

val list = ArrayList<Integer>()  
list.add(1) // int自动装箱为Integer → 产生额外对象  

val list = IntArray(10) // 直接使用基本类型数组  
list[0] = 1  

private val viewHolderPool = Pools.SimplePool<ViewHolder>(10)  

fun create(): ViewHolder {  
    return viewHolderPool.acquire() ?: ViewHolder(...)  
}  

fun recycle(viewHolder: ViewHolder) {  
    viewHolderPool.release(viewHolder)  
}