androidx。Core-ktx已经有了

/**
 * Performs the given action when this view is next laid out.
 *
 * The action will only be invoked once on the next layout and then removed.
 *
 * @see doOnLayout
 */
public inline fun View.doOnNextLayout(crossinline action: (view: View) -> Unit) {
    addOnLayoutChangeListener(object : View.OnLayoutChangeListener {
        override fun onLayoutChange(
            view: View,
            left: Int,
            top: Int,
            right: Int,
            bottom: Int,
            oldLeft: Int,
            oldTop: Int,
            oldRight: Int,
            oldBottom: Int
        ) {
            view.removeOnLayoutChangeListener(this)
            action(view)
        }
    })
}

/**
 * Performs the given action when this view is laid out. If the view has been laid out and it
 * has not requested a layout, the action will be performed straight away, otherwise the
 * action will be performed after the view is next laid out.
 *
 * The action will only be invoked once on the next layout and then removed.
 *
 * @see doOnNextLayout
 */
public inline fun View.doOnLayout(crossinline action: (view: View) -> Unit) {
    if (ViewCompat.isLaidOut(this) && !isLayoutRequested) {
        action(this)
    } else {
        doOnNextLayout {
            action(it)
        }
    }
}

通常方法的另一种替代方法是钩入视图的绘图。

OnPreDrawListener在显示视图时被多次调用，因此没有特定的迭代，其中您的视图具有有效的测量宽度或高度。这要求您不断地验证(view.getMeasuredWidth() <= 0)或设置检查measuredWidth大于零的次数限制。

也有可能永远不会绘制视图，这可能表明您的代码存在其他问题。

final View view = [ACQUIRE REFERENCE]; // Must be declared final for inner class
ViewTreeObserver viewTreeObserver = view.getViewTreeObserver();
viewTreeObserver.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
    @Override
    public boolean onPreDraw() {
        if (view.getMeasuredWidth() > 0) {     
            view.getViewTreeObserver().removeOnPreDrawListener(this);
            int width = view.getMeasuredWidth();
            int height = view.getMeasuredHeight();
            //Do something with width and height here!
        }
        return true; // Continue with the draw pass, as not to stop it
    }
});

要避免弃用代码和警告，您可以使用:

view.getViewTreeObserver().addOnGlobalLayoutListener(
        new ViewTreeObserver.OnGlobalLayoutListener() {
            @SuppressWarnings("deprecation")
            @Override
            public void onGlobalLayout() {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
                    view.getViewTreeObserver()
                            .removeOnGlobalLayoutListener(this);
                } else {
                    view.getViewTreeObserver()
                            .removeGlobalOnLayoutListener(this);
                }
                yourFunctionHere();
            }
        });

我创建静态变量来检查布局是否已经绘制。如果它已经创建，你可以简单地调用绘制的函数。

static int firstAccess = 0;
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main8);

    if (firstAccess==0) {
        LAYOUT_YOU_DRAW.post(new Runnable() {
            @Override
            public void run() {
                creatSpread();
                firstAccess = 1;
            }
        });
    }else{
        creatSpread();
    }
}

如果您正在使用kotlin，我建议您使用doOnLayout

doOnLayout {
    doWhateverYouNeed()
}

道格: 在布局此视图时执行给定的操作

视图。post {TODO(“尚未实现”)}