IOS开发之UIButton同时设置图片文字以及触发按钮时文字图片的切换

在应用UIBUtton的时候我们有时需要同时设置图片和文字，下面代码仅供参考：

UIButton *_backButton = [UIButton buttonWithType:UIButtonTypeCustom];

[_backButton setFrame:CGRectMake(12, 8, 64, 28)];

[_backButton setTitle:@"返回" forState:UIControlStateNormal]; //设置button在没有选中的时候显示的字体

_backButton.titleLabel.font = [UIFont systemFontOfSize:14.0f]; //设置button显示字体的大小

[_backButton setBackgroundImage:[UIImage imageNamed:@"backButton.png"]forState:UIControlStateNormal];
//设置button背景显示图片

[self.view addSubview:_backButton];

出了上面的操作意外，我们还可以同时设置button在选中（按下之后）以及正常状态下（没有选中）显示文字和图片的不同，

UIButton *_backButton = [UIButton buttonWithType:UIButtonTypeCustom];

[_backButton setFrame:CGRectMake(12, 8, 64, 28)];

[_backButton setTitle:@"返回" forState:UIControlStateNormal];

[_backButton setTitle:@"Down" forState:UIControlStateHighlighted];

[_backButton setBackgroundColor:[UIColor clearColor]];

[_backButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];

_backButton.titleLabel.font = [UIFont systemFontOfSize:14.0f];

[_backButton setBackgroundImage:[UIImage imageNamed:@"backButton.png"]forState:UIControlStateNormal];

[_backButton setBackgroundImage:[UIImage imageNamed:@"DownButton.png"] forState:UIControlStateNormal];

[_toolBar addSubview:_backButton];