Super Bright FlashLight shows a simple demo of controlling flashlight on OpenHarmony device.

This documentation also listed all the problems or noticeable thing during the app development.

Functionaility

General Process

Problems encountered during development

1. To run and debug the Harmony device configure the HarmonyOS runtime

2. Change the HarmonyOS project back to OpenHarmony

This part introduces the general process of the application development

1. UI design and implement
2. Logic and functionailities
3. Check and testing
4. App display and acceptance
5. Add all necessary files
6. Merge to applist and finish

•  Provide a simple UI page with a slider. When we slide the bar to the top direction, the flashlight will goes brighter, vice versa.

•  When we slide the bar, an `Off` button will pop up, click this button will reset the slider and turn off the flashlight.

• Take the example of Super Bright FlashLight, we are aiming to design the app with user-friendly interface. Comunicate with UI/UX colleague and got the basic construction idea.

• After that, start to build the UI part, my idea is to construct the UI with very simple containers(Like placing columns/rows with a different color to make a general position layout)

• Then, start to replce each component with the containers

In my case I need to place a flashlight image as background, and a fragemented slider to control the flashlight's brightness, so choose Stack as the basic container.

• After basic logic constrcution we can start to write the logic part.

Note
There is some basic logic code within UI part, general it's inside the callback function of some User-interacting Component like Button(), Slider(), TextInput() and etc.

• The User-interacting UI component can control the UI variables which defined inside the struct.

@Entry
@Component
struct Index{
@State isOn: boolean = false
  build(){
    Button('Click')
    .onClick(()=>{
    this.isOn = this.isOn ? true : false
    })
  }
}

Note
We need to define the UI state variable within struct, and to update it in callback functions.

Start fullfilling the callback function with some basic console.info() about the operation, then add the more concrete logic afterwords.

• For most of other logic like flashlight api calls create another folder under src/main/ets maybe name it as Api

• Using import and export to pass the logic function between UI.

// ets/Api

// Get camera manager instance
export default function getCameraManager(context: common.BaseContext): camera.CameraManager | undefined {
  let cameraManager: camera.CameraManager | undefined = undefined;
  try {
    cameraManager = camera.getCameraManager(context);
  } catch (error) {
    let err = error as BusinessError;
    console.error(`The getCameraManager call failed. error code: ${err.code}`);
  }
  return cameraManager;
}

//Your UI page
import getCameraManager from './Api'

@Entry
@Component
struct index{
      private cameraManager: camera.CameraManager = getCameraManager(getContext(this)) as camera.CameraManager
      build(){
      }
}

Note
In such case you can call the GetCameraManager function from your Api folder.

• I use console/hilog to check the program works fine or not. Most of the UI part can be tested in Previewer , some functionailities can be tested in Emulator like App Stages, Web component, http interaction, and some functionailities can be tested only on real development board like Camera, flashlight which exists only on real device.

After connecting OpenHarmony board, it shows no device on Deveco Studio. But in the terminal type hdc list targets it shows the connected device series number.

Solution: Reinstall pervious same Deveco studio version and run the sync again.

After concrete debugging and checking, it's still the device problem. So for this application I keep only simple demo with UI functionalities.

Update information

I tested the api with HarmonyOS device and it worked, so I keep these functionailities and attached to the button.

CONTENT TO BE ADDED

• Add LICENSE file We can add the LICENSE via here.

CONTENT TO BE ADDED

In order to test the project on emulator we need to install Deveco Studio 5.0, since the system-image through our welink resource is HarmonyOS device, we can't simply deploy our OpenHarmony project on it. Therefore, we need to change a bit of OpenHarmony project to make it working.

in build-profile.json file, comment on the OpenHarmony products configuration, replace it when HarmonyOS products configuration shown as follows.

    "products": [
      {
        "name": "default",
        "signingConfig": "default",
        "compatibleSdkVersion": "4.1.0(11)",
        "runtimeOS": "HarmonyOS",
        "buildOption": {
          "strictMode": {
            "caseSensitiveCheck": true,
          }
        }
      }
    ],
    //    "products": [
    //      {
    //        "name": "default",
    //        "signingConfig": "default",
    //        "compileSdkVersion": 11,
    //        "compatibleSdkVersion": 11,
    //        "runtimeOS": "OpenHarmony",
    //      }
    //    ],

https://www.cnblogs.com/changyiqiang/p/17954322

Then after the testing is done, we want the project run under OpenHarmony environment again.

in build-profile.json file, uncomment the OpenHarmony products configuration, comment the HarmonyOS products configuration shown as follows.

    // "products": [
    //   {
    //     "name": "default",
    //     "signingConfig": "default",
    //     "compatibleSdkVersion": "4.1.0(11)",
    //     "runtimeOS": "HarmonyOS",
    //     "buildOption": {
    //       "strictMode": {
    //         "caseSensitiveCheck": true,
    //       }
    //     }
    //   }
    // ],
       "products": [
         {
           "name": "default",
           "signingConfig": "default",
           "compileSdkVersion": 11,
           "compatibleSdkVersion": 11,
           "runtimeOS": "OpenHarmony",
         }
       ],

Then under the route hvigor\hvigor-profile.json5, altering the version and dependencies back as follows

Since it's version was too high

  "hvigorVersion": "3.2.4",
  "dependencies": {
    "@ohos/hvigor-ohos-plugin": "3.2.4"
  },

After that, run the sync operation again, the project should be working now.