Question

我有一个方法，在TextView和Button上将VectorDrawable设置为DrawableLeft，DrawableRight等，但我想让它也适用于普通的Drawable。那么，有没有办法检查DrawableRes的类型，还是应该使用try / catch？该方法如下所示：

public static void setViewDrawables(@NonNull View view, @DrawableRes int left, @DrawableRes int top, @DrawableRes int right, @DrawableRes int bottom) {
    final Resources resources = view.getResources();
    Drawable vectorDrawableLeft = left != 0 ? VectorDrawableCompat.create(resources, left, view.getContext().getTheme()) : null;
    Drawable vectorDrawableTop = top != 0 ? VectorDrawableCompat.create(resources, top, view.getContext().getTheme()) : null;
    Drawable vectorDrawableRight = right != 0 ? VectorDrawableCompat.create(resources, right, view.getContext().getTheme()) : null;
    Drawable vectorDrawableBottom = bottom != 0 ? VectorDrawableCompat.create(resources, bottom, view.getContext().getTheme()) : null;

    if (view instanceof Button) {
        ((Button) view).setCompoundDrawablesWithIntrinsicBounds(vectorDrawableLeft, vectorDrawableTop, vectorDrawableRight, vectorDrawableBottom);
    }
    else if (view instanceof TextView) {
        ((TextView) view).setCompoundDrawablesWithIntrinsicBounds(vectorDrawableLeft, vectorDrawableTop, vectorDrawableRight, vectorDrawableBottom);
    } else {
        Log.e("ERROR: ViewUtils", "Can't do setCompoundDrawablesWithIntrinsicBounds on " + view.getClass().getName());
    }
}

Answer 1

总结评论的答案。据我所知，没有简单的方法可以知道DrawableRes是否指向VectorDrawable。如果有人知道怎么做，请写信。但是为了解决我的问题，使用android.support.v7.content.res.AppCompatResources就足够了@pskink建议。所以现在方法看起来像：

public static void setViewDrawables(@NonNull View view, @DrawableRes int left, @DrawableRes int top, @DrawableRes int right, @DrawableRes int bottom) {
    Drawable vectorDrawableLeft = left != 0 ? AppCompatResources.getDrawable(view.getContext(), left) : null;
    Drawable vectorDrawableTop = top != 0 ? AppCompatResources.getDrawable(view.getContext(), top) : null;
    Drawable vectorDrawableRight = right != 0 ? AppCompatResources.getDrawable(view.getContext(), right) : null;
    Drawable vectorDrawableBottom = bottom != 0 ? AppCompatResources.getDrawable(view.getContext(), bottom) : null;

    if (view instanceof Button) {
        ((Button) view).setCompoundDrawablesWithIntrinsicBounds(vectorDrawableLeft, vectorDrawableTop, vectorDrawableRight, vectorDrawableBottom);
    } else if (view instanceof TextView) {
        ((TextView) view).setCompoundDrawablesWithIntrinsicBounds(vectorDrawableLeft, vectorDrawableTop, vectorDrawableRight, vectorDrawableBottom);
    } else {
        Log.e("ERROR: ViewUtils", "Can't do setCompoundDrawablesWithIntrinsicBounds on " + view.getClass().getName());
    }
}

<强>更新

在android.support.v7.widget.AppCompatDrawableManager中有一个方法boolean isVectorDrawable(@NonNull Drawable d)，它检查Drawable是否为VectorDrawable，但是它将Drawable作为参数，而不是DrawableRes。它看起来像这样：

private static boolean isVectorDrawable(@NonNull Drawable d) {
    return d instanceof VectorDrawableCompat
          || PLATFORM_VD_CLAZZ.equals(d.getClass().getName());
}

检查DrawableRes是否为VectorDrawable

1 个答案: