Android自定義ViewGroup多行多列效果

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本文實例為大傢分享瞭Android自定義ViewGroup多行多列的具體代碼，供大傢參考，具體內容如下

先看下效果圖

每行兩個子孩子

每行一個子孩子

實現思路

自定義viewGroup,實現測量和佈局，使控件適應業務場景。

測量

根據父控件的寬度，平均分給每個子孩子固定的寬度。高度就是行數乘以一個子孩子的高度，再加上空隙的高度。

根據子孩子個數計算行數  

val rows = if (childCount % perLineChild == 0) {
            childCount / perLineChild
        } else {
            childCount / perLineChild + 1
        }

代碼示例

override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        val width = MeasureSpec.getSize(widthMeasureSpec)
        for (i in 0 until childCount) {
            val child: View = getChildAt(i)
            if (child.visibility != GONE) {
                val lp = child.layoutParams
                val childWidthMeasureSpec = getChildMeasureSpec(
                    widthMeasureSpec,
                    0, (width - (perLineChild - 1) * space) / perLineChild
                )
                val childHeightMeasureSpec = getChildMeasureSpec(
                    heightMeasureSpec,
                    0, lp.height
                )
                child.measure(childWidthMeasureSpec, childHeightMeasureSpec)
            }
        }
        val rows = if (childCount % perLineChild == 0) {
            childCount / perLineChild
        } else {
            childCount / perLineChild + 1
        }
        if (childCount > 0) {
            setMeasuredDimension(
                width,
                getChildAt(0).measuredHeight * rows + (rows - 1) * space
            )
        }
    }

佈局

需要註意擺放的順序和位置，每行擺放固定的個數，達到個數之後換行繼續擺放

代碼示例 

override fun onLayout(changed: Boolean, l: Int, t: Int, r: Int, b: Int) {
        var left = l
        var top = t
        children.forEachIndexed { index, view ->
            if (index % perLineChild == 0) {
                left = 0
                if (index != 0) {
                    top += view.measuredHeight
                    top+=space
                }
                view.layout(left, top, view.measuredWidth + left, top + view.measuredHeight)
            } else {
                view.layout(left, top, view.measuredWidth + left, top + view.measuredHeight)
            }
            left += view.measuredWidth
            left += space
        }
    }

完整代碼

class MultiLineViewG @JvmOverloads constructor(
    context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0
) : ViewGroup(context, attrs, defStyleAttr) {

    var perLineChild = 2

    /**
     * 子孩子之間的空隙
     */
    var space = 10

    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        val width = MeasureSpec.getSize(widthMeasureSpec)
        for (i in 0 until childCount) {
            val child: View = getChildAt(i)
            if (child.visibility != GONE) {
                val lp = child.layoutParams
                val childWidthMeasureSpec = getChildMeasureSpec(
                    widthMeasureSpec,
                    0, (width - (perLineChild - 1) * space) / perLineChild
                )
                val childHeightMeasureSpec = getChildMeasureSpec(
                    heightMeasureSpec,
                    0, lp.height
                )
                child.measure(childWidthMeasureSpec, childHeightMeasureSpec)
            }
        }
        val rows = if (childCount % perLineChild == 0) {
            childCount / perLineChild
        } else {
            childCount / perLineChild + 1
        }
        if (childCount > 0) {
            setMeasuredDimension(
                width,
                getChildAt(0).measuredHeight * rows + (rows - 1) * space
            )
        }
    }

    override fun onLayout(changed: Boolean, l: Int, t: Int, r: Int, b: Int) {
        var left = l
        var top = t
        children.forEachIndexed { index, view ->
            if (index % perLineChild == 0) {
                left = 0
                if (index != 0) {
                    top += view.measuredHeight
                    top+=space
                }
                view.layout(left, top, view.measuredWidth + left, top + view.measuredHeight)
            } else {
                view.layout(left, top, view.measuredWidth + left, top + view.measuredHeight)
            }
            left += view.measuredWidth
            left += space
        }
    }
}

以上就是本文的全部內容，希望對大傢的學習有所幫助，也希望大傢多多支持WalkonNet。

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