怎么通过代码设置选中位置

[BloodBamboo]

setSelectedItem 方法无效

[IRMobydick]

without animation:

public void setSelectedItem(int position) {
    if(position < 0 || position >= getCount()){
        throw new IllegalArgumentException("position error");
    }
    this.selectedItem = position;
    requestLayout(); <- add this
    invalidate();

}

with animation:

public void setSelectedItem(int position) {
    if(position < 0 || position >= getCount()){
        throw new IllegalArgumentException("position error");
    }
    this.selectedItem = position;
    startScroll(getXByPosition(selectedItem)); <- add this
}