Creating a Spinner near the bottom of an activity should force it to open upwards, given there isn't enough space to list downwards. A way of forcing using this would be to add a margin to the top of your spinner to force it down so it will list upwards.
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与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…