//重寫方法

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view{

    UILabel* pickerLabel = (UILabel*)view;

    if (!pickerLabel){

        pickerLabel = [[UILabel alloc] init];

        // Setup label properties - frame, font, colors etc

        //adjustsFontSizeToFitWidth property to YES

        pickerLabel.adjustsFontSizeToFitWidth = YES;

        [pickerLabel setTextAlignment:NSTextAlignmentLeft];

        [pickerLabel setBackgroundColor:[UIColor clearColor]];

        [pickerLabel setFont:[UIFont boldSystemFontOfSize:15]];

    }

    // Fill the label text here

    pickerLabel.text=[self pickerView:pickerView titleForRow:row forComponent:component];

    return pickerLabel;

}