Question

我在iphone应用程序上工作，我必须合并三个图像并使它们成为单个图像。我的意思是说我有一个背景图像，一个标题图像和较低的图像，我需要将所有这些组合成一个单一的图像，所以我可以使用它发布到Facebook。感谢。

*的修改 * 我知道这两个图像的代码，但我如何将它用于三个图像：

UIGraphicsBeginImageContext(saveView.bounds.size);
[saveView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *finalImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

Answer 1

你可以在一个UIView中对齐它们（我想甚至在屏幕外但我还没有检查过） - 然后使用QuartzCode将UIView转换为UIImage：

UIGraphicsBeginImageContext(myView.bounds.size);
[myView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

然后将其转换为格式 - 例如PNG：

NSData *imageData = UIImagePNGRepresentation(image);

然后发送应该不会太困难。

修改这是一个扩展示例，您还可以看到3个图像 - 您当然可以使用Interface Builder和Outlets而不是全部编写 - 但是您可以复制粘贴以尝试：

UIImageView *imgView1, *imgView2, *imgView3; imgView1 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"image1"]]; imgView2 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"image2"]]; imgView3 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"image3"]]; imgView1.frame = CGRectMake(0, 0, 50, 50); imgView2.frame = CGRectMake(50, 50, 100, 100); imgView3.frame = CGRectMake(100, 100, 200, 200); [referenceView addSubview:imgView1]; [referenceView addSubview:imgView2]; [referenceView addSubview:imgView3]; UIGraphicsBeginImageContext(referenceView.bounds.size); [referenceView.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *finalImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); resultView = [[UIImageView alloc] initWithImage:finalImage]; resultView.frame = CGRectMake(0, 0, 320, 480); [self.view addSubview:resultView]; referenceView.hidden = YES;

注意我已经检查过UIView在你调用renderInContext时必须是可绘制的/可见的（它可以在屏幕外但不能隐藏或alpha = 0，因为它将呈现为不可见）。所以要么把它放在屏幕外，要么在绘制后立即隐藏它

Answer 2

Shein的回答帮助了我，但我发现我没有必要将UIView添加到主视图中以进行渲染。以下是向图像添加文本的示例...

    UIImage *image = [UIImage imageNamed:@"toolbar_icon"]; // image is 20 x 20 .png

    UIView *tempView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, image.size.width, image.size.height)];
    [tempView addSubview:[[UIImageView alloc] initWithImage:image]];

    UILabel *label = [[UILabel alloc] initWithFrame:tempView.frame];
    [label setText:[NSString stringWithFormat:@"%d", [self countValue]]];
    [label setFont:[UIFont systemFontOfSize:22.0]];
    [label setTextColor:[UIColor lightTextColor]];
    [label setTextAlignment:UITextAlignmentCenter];
    [label setBackgroundColor:[UIColor clearColor]];
    [tempView addSubview:label];

    UIGraphicsBeginImageContext(tempView.bounds.size);
    [tempView.layer renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *finalImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    UIBarButtonItem *countItem = [[UIBarButtonItem alloc] initWithImage:finalImage
                                                                       style:UIBarButtonItemStyleBordered
                                                                      target:self
                                                                      action:@selector(countAction:)];

注意：我突然意识到我的答案包括为图像添加标签，这是我在发现之前尝试做的事情。参考Combine Label Text With Image

Iphonesdk合并三张图片两张单张图片

2 个答案: