1.設置tetxField的內邊距
[self.yourTextField setValue:[NSNumber numberWithInt:5] forKey:@”paddingTop”];
[self.yourTextField setValue:[NSNumber numberWithInt:5] forKey:@”paddingLeft”];
[self.yourTextField setValue:[NSNumber numberWithInt:5] forKey:@”paddingBottom”];
[self.yourTextField setValue:[NSNumber numberWithInt:5] forKey:@”paddingRight”];
2.設置textfield的leftView 喂一個帶有寬度的view