SCADE

Image control

SCADE 2.0 - Displaying images using Swift on Android and iOS

📘

Source code

Please see the UgBitmapDemo project for the source code created in this chapter. See Installing examples for information on how to download the examples. The URL is here for direct access is https://github.com/scadedoc/UgExamples/tree/master/UgSqlLiteSwift

Introduction

Using the bitmap control, you can display images sourced from within the app or dynamically downloaded from the internet.

As with all of our controls, the controls represent a wrapper around the native controls and expose a subset of its functionality to user:

  • We support the following formats : PNG, SVG, JPG
  • We support SVG based scaling of the bitmap

Control attributes

Attribute Name

Attribute Type

Attribute Meaning

Example

content

String!

Field to store the actual image data that you want to display

Binary data

url

String!

Relative path to the source of the image. Make sure you specify the correct path. It starts with the name of the resource folder followed by the image name.

You can only specify relative URLs that are local to the app directory structure. External URLs such as http:\...\myimage.png are currently not supported.

Correct
res/dog.png

Wrong:

  • /Appname/res/dog.png
  • /res/dog/png
  • http:\...\mydog.png

isContentPriority

Bool

Defines which inbound source is used to display the image
False, i.e. image data is retrieved using information in url field
True, i.e. image data is taken from the content field

Static image references

In order to put an image stored on the app, please put the image/bitmap into the Assets folder (or a subfolder). You can then use the image control to add a new image to your app:

Scade mode and alignment

The scale mode describes how the bitmap fits into the current area. You can combine the scale mode and the alignment for best fit.

  • Scale mode: none, Fit into Parent (Meet), Fill Parent (slice)
  • Alignment (9 different positions)

📘

Scaling Factor Articles

These articles explain scaling factor in detail. In case its needed

Setting bitmaps using code

You always have to make TWO settings

  • make sure you specify the path in the url field correctly. It's /<image.png|jpg|svg>
  • make sure you set the isContentPriority to false
import ScadeKit
  
class BindingAndScalePagePageAdapter: SCDLatticePageAdapter {
  
  // page adapter initialization
  override func load(_ path: String) {
    super.load(path)
    
    self.image1.url = "Assets/dog2.jpg"
    self.image1.contentPriority = false
    
    self.main.onClick.append(SCDWidgetsEventHandler{_ in self.navigation!.go(page: "main.page")})
  }
}

Setting images using raw data from download

To use images that don't exist on the app yet, we use the SCDNetworkRequest and SCDNetworkResponse objects to download the data:

  • set the content field with the raw image data received from the network call
  • make sure you set the isContentPriority to true
import ScadeKit

class MainPageAdapter: SCDLatticePageAdapter {
    
    // page adapter initialization
    override func load(_ path: String) {        
        super.load(path)
        
        // adding 2nd page btn 
        self.itmBinding.onClick{_ in self.navigation!.go(page: "BindingAndScalePage.page")}
        
        
        // get reference to second bitmap and set bitmap
        self.image2.url = "Assets/dog2.jpg"
        self.image2.contentPriority = false
        
        let externalurl = "https://s3.amazonaws.com/scade.io/demo/documentation/dog3.jpg"
        let request = SCDNetworkRequest()
        request.url = externalurl
        if let response = request.call() {
            self.image3.content = response.body
            self.image3.contentPriority = true
        }
        
    }
}

Updated 3 months ago

Image control


SCADE 2.0 - Displaying images using Swift on Android and iOS

Suggested Edits are limited on API Reference Pages

You can only suggest edits to Markdown body content, but not to the API spec.