ios - 将配置图像解析为 UIImageView

Question

我在 Parse.com 上的应用“Config”中添加了一张图片，但我不确定如何从“Config”下载图片并在下载后在我的应用的 UIImageView 中显示它.

Answer 1

这就是我喜欢 Parse.com 的原因，它们让开发人员的工作变得如此简单。

第 1 步 在 Parse.com 的配置管理 View 中设置您的参数。对于图像，您必须确保将其设置为 PFFile，并根据您的需要命名。

第 2 步 在需要调用 Config 参数的任何地方(不限于图像)实现 getConfigInBackground: 方法

[PFConfig getConfigInBackgroundWithBlock:^(PFConfig *config, NSError *error) {
    //In my case I have a BOOL statement, that if it is set to false, it won't show the config image I uploaded, it will show a placeholder image stored in the bundle
    if ([config[@"bannerisTrue"] boolValue]) {
        //The bannerisTrue boolValue is true so that means I want to retrieve the image from Config to display in the app
        PFFile *banner1 = config[@"banner1"]; //You reference the image as a PFFile first before retrieving the data, and you're telling the query to specify the config column 'banner1'. Kind of like `selectKeys:`
        [banner1 getDataInBackgroundWithBlock:^(NSData *data, NSError *error) {
            UIImageView *bannerView = [[UIImageView alloc] initWithFrame:/*init how ever you want or place in whatever UIImageView you have a IBOutlet for */]; 
            bannerView.image = [UIImage imageWithData:data]; //Your image is now in the UIImageView that you have set.
            }];
    } else {
        UIImageView *bannerView = [[UIImageView alloc] initWithFrame:/*same frame as above*/];
        bannerView.image = [UIImage imageNamed:@"placeholderimage.jpg"]; //Since the boolValue is false we want to have a placeholder image so that way the app is more fluid. This is also good to have in case internet issues arise. This image is the one stored on device
    }
}];