TextInputLayout.java 文件源码

private void ensureBackgroundDrawableStateWorkaround() {
    Drawable bg = this.mEditText.getBackground();
    if (bg != null && !this.mHasReconstructedEditTextBackground) {
        Drawable newBg = bg.getConstantState().newDrawable();
        if (bg instanceof DrawableContainer) {
            this.mHasReconstructedEditTextBackground = DrawableUtils.setContainerConstantState((DrawableContainer) bg, newBg.getConstantState());
        }
        if (!this.mHasReconstructedEditTextBackground) {
            this.mEditText.setBackgroundDrawable(newBg);
            this.mHasReconstructedEditTextBackground = true;
        }
    }
}