如何在android中获取弹出菜单的高度和宽度？

Question

我有一个弹出菜单，我只想获取它的尺寸以在我的 showCaseView 中用于我的导览。 我在任何地方都找不到确定这些尺寸（高度和宽度）的方法。

private void initPopUpMenu() {
    PopupMenu popupMenu = new PopupMenu(TimelineActivity.this, menuIcon);
    popupMenu.getMenuInflater().inflate(R.menu.menu_timeline, popupMenu.getMenu());
}

如何从这个结构中检索宽度和高度？ 这是一个简单的菜单资源，有 5 个项目

Answer 1

最好的解决方案是使用ListPopupWindow而不是PopupMenu ，后者具有getWidth()和getHeight()方法来获取其尺寸。 但是，如果您真的想使用PopupMenu ，可能的棘手方法是使用Reflection访问其内部ListView ，因为PopupMenu没有可用的方法来访问内容视图。

用法：

PopupMenu popupMenu = initPopUpMenu();
popupMenu.show();

ListView listView = getPopupMenuListView(popupMenu);

androidx.core.view.ViewKt.doOnLayout(listView, view -> {
    System.out.println("PopupMenu Size: " + view.getWidth() + " x " + view.getHeight());
    return null;
});

方法：

private PopupMenu initPopUpMenu() {
    PopupMenu popupMenu = new PopupMenu(TimelineActivity.this, menuIcon);
    popupMenu.getMenuInflater().inflate(R.menu.menu_timeline, popupMenu.getMenu());
    return popupMenu;
}

private ListView getPopupMenuListView(PopupMenu popupMenu) {
    Method getMenuListViewMethod = null;
    try {
        getMenuListViewMethod = PopupMenu.class.getDeclaredMethod("getMenuListView");
    } catch (NoSuchMethodException e) {
        e.printStackTrace();
    }

    ListView listView = null;
    if (getMenuListViewMethod != null) {
        getMenuListViewMethod.setAccessible(true);
        try {
            listView = (ListView) getMenuListViewMethod.invoke(popupMenu);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
    return listView;
}

构建.gradle：

android {
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
}

dependencies {
    implementation 'androidx.core:core-ktx:1.3.0'
}

结果：

I/System.out：弹出菜单大小：539 x 660

Answer 2

您可以在PopupWindow使用自定义布局，然后对其进行测量

val popupWindow = PopupWindow(context)
popupWindow.contentView = View.inflate(context, R.layout.my_popup, null).apply {
    measure(
        View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
        View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED)
    )
    measuredWidth// <-- here is width
    measuredHeight// <-- here is height
}