Question

目标：

触摸内部时，按钮背景图像会改变

代码：

- (void)addMyButton{    // Method for creating button, with background image and other properties

    UIButton *playButton = [[UIButton buttonWithType:UIButtonTypeRoundedRect] retain];
    [self.view addSubview:playButton];
    playButton.frame = CGRectMake(150, 150, 100, 100);
    //set title,backgroundcolor...

    UIImage *buttonImageNormal = [UIImage imageNamed:@"red.png"];
    UIImage *strechableButtonImageNormal = [buttonImageNormal stretchableImageWithLeftCapWidth:0 topCapHeight:0];
    [playButton setBackgroundImage:strechableButtonImageNormal forState:UIControlStateNormal];

    if([playButton isTouchInside:[UIImage buttonImageNormal]]) //This line warning
    {
        UIImage *buttonImageNormal2 = [UIImage imageNamed:@"yellow.png"];
        UIImage *strechableButtonImageNormal2 = [buttonImageNormal2 stretchableImageWithLeftCapWidth:12 topCapHeight:0];
        [playButton setBackgroundImage:strechableButtonImageNormal2 forState:UIControlStateNormal];

    }
}

请告诉我目前在警戒线上所做的事情。告诉我有什么错误。并告诉我'isTouchInside'的语法。如果你愿意，请实现我的目标。

Answer 1

尝试更改：

if([playButton isTouchInside:[UIImage buttonImageNormal]])

要：

if([playButton isTouchInside])

isTouchInside不接受任何参数

Answer 2

您尝试调用名为isTouchInside:的不存在的方法，该方法将UIImage作为参数。你可能想要isTouchInside，它不带任何参数。你应该使用那个。

Answer 3

如果您希望按钮响应触摸事件，也许您应该添加以下代码：

[playButton addTarget: self action:@selector(playButtonPressed:) forControlEvents: UIControlEventTouchUpInside];

然后添加此功能：

- (void) playButtonPressed: (id) sender{
    UIImage *buttonImageNormal2 = [UIImage imageNamed:@"yellow.png"];
    UIImage *strechableButtonImageNormal2 = [buttonImageNormal2 stretchableImageWithLeftCapWidth:12 topCapHeight:0];
    [playButton setBackgroundImage:strechableButtonImageNormal2 forState:UIControlStateNormal];
}

并删除if([playButton isTouchInside]）块。这可确保按钮随时响应触摸，而不是仅在创建时响应。

警告：＆＃39; isTouchInside＆＃39;如果条件

3 个答案: