# Updating Widget Content by State


Multiple widgets of the same application can be configured to implement different features. For example, two weather widgets can be added to the home screen: one for displaying the weather of London, and the other Beijing. The widget is set to be updated at 07:00 every morning. It needs to detect the configured city, and then updates the city-specific weather information. The following example describes how to dynamically update the widget content based on the state.


- Widget configuration file: Configure the widget to be updated at 07:00 every morning.
  
  ```json
  {
    "forms": [
      {
        "name": "widget",
        "description": "This is a service widget.",
        "src": "./ets/widget/pages/WidgetCard.ets",
        "uiSyntax": "arkts",
        "window": {
          "designWidth": 720,
          "autoDesignWidth": true
        },
        "colorMode": "auto",
        "isDefault": true,
        "updateEnabled": true,"scheduledUpdateTime": "07:00",
        "updateDuration": 0,
        "defaultDimension": "2*2",
        "supportDimensions": ["2*2"]
      }
    ]
  }
  ```

- Widget page: A widget has different states and needs to be updated by state. When the state changes, **postCardAction** is called to notify the EntryFormAbility.
  
  ```ts
  let storage = new LocalStorage();
  @Entry(storage)
  @Component
  struct WidgetCard {
    @LocalStorageProp('textA') textA: string = 'To be updated...';
    @LocalStorageProp('textB') textB: string ='To be updated...';
    @State selectA: boolean = false;
    @State selectB: boolean = false;
  
    build() {
      Column() {
        Row() {
          Checkbox({ name: 'checkbox1', group: 'checkboxGroup' })
            .select(false)
            .onChange((value: boolean) => {
              this.selectA = value;
              postCardAction(this, {
                'action': 'message',
                'params': {
                  'selectA': JSON.stringify(value)
                }
              });
            })
          Text ('State A')
        }
  
        Row() {
          Checkbox({ name: 'checkbox2', group: 'checkboxGroup' })
            .select(false)
            .onChange((value: boolean) => {
              this.selectB = value;
              postCardAction(this, {
                'action': 'message',
                'params': {
                  'selectB': JSON.stringify(value)
                }
              });
            })
          Text ('State B')
        }
  
        Row() {// Content that is updated only in state A
          Text('State A: ')
          Text(this.textA)
        }
  
        Row() { // Content that is updated only in state B
          Text ('State B:')
          Text(this.textB)
        }
      }.padding('10%')
    }
  }
  ```
  
- EntryFormAbility: The widget state data is stored in the local database. When the update event callback is triggered, the current widget state is obtained through **formId**, and then content is updated based on the state obtained.
  
  ```ts
  import formInfo from '@ohos.app.form.formInfo'
  import formProvider from '@ohos.app.form.formProvider';
  import formBindingData from '@ohos.app.form.formBindingData';
  import FormExtensionAbility from '@ohos.app.form.FormExtensionAbility';
  import dataStorage from '@ohos.data.storage'
  
  export default class EntryFormAbility extends FormExtensionAbility {
    onAddForm(want) {
      let formId = want.parameters[formInfo.FormParam.IDENTITY_KEY];
      let isTempCard: boolean = want.parameters[formInfo.FormParam.TEMPORARY_KEY];
      if (isTempCard === false) {// If the widget is a normal one, the widget information is persisted.
        console.info('Not temp card, init db for:' + formId);
        let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore')
        storeDB.putSync('A' + formId, 'false');
        storeDB.putSync('B' + formId, 'false');
        storeDB.flushSync();
      }
      let formData = {};
      return formBindingData.createFormBindingData(formData);
    }
  
    onRemoveForm(formId) {
      console.info('onRemoveForm, formId:' + formId);
      let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore')
      storeDB.deleteSync('A' + formId);
      storeDB.deleteSync('B' + formId);
    }
  
    // If the widget is a temporary one, it is recommended that the widget information be persisted when the widget is converted to a normal one.
    onCastToNormalForm(formId) {
      console.info('onCastToNormalForm, formId:' + formId);
      let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore')
      storeDB.putSync('A' + formId, 'false');
      storeDB.putSync('B' + formId, 'false');
      storeDB.flushSync();
    }
  
    onUpdateForm(formId) {
      let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore')
      let stateA = storeDB.getSync('A' + formId, 'false').toString()
      let stateB = storeDB.getSync('B' + formId, 'false').toString()
      // Update textA in state A.
      if (stateA === 'true') {
        let formInfo = formBindingData.createFormBindingData({
          'textA': 'AAA'
        })
        formProvider.updateForm(formId, formInfo)
      }
      // Update textB in state B.
      if (stateB === 'true') {
        let formInfo = formBindingData.createFormBindingData({
          'textB': 'BBB'
        })
        formProvider.updateForm(formId, formInfo)
      }
    }
  
    onFormEvent(formId, message) {
      // Store the widget state.
      console.info('onFormEvent formId:' + formId + 'msg:' + message);
      let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore')
      let msg = JSON.parse(message)
      if (msg.selectA != undefined) {
        console.info('onFormEvent selectA info:' + msg.selectA);
        storeDB.putSync('A' + formId, msg.selectA);
      }
      if (msg.selectB != undefined) {
        console.info('onFormEvent selectB info:' + msg.selectB);
        storeDB.putSync('B' + formId, msg.selectB);
      }
      storeDB.flushSync();
    }
  };
  ```


> **NOTE**
> When the local database is used for widget information persistence, it is recommended that [TEMPORARY_KEY](../reference/apis/js-apis-app-form-formInfo.md#formparam) be used to determine whether the currently added widget is a normal one in the [onAddForm](../reference/apis/js-apis-app-form-formExtensionAbility.md#onaddform) lifecycle callback. If the widget is a normal one, the widget information is directly persisted. If the widget is a temporary one, the widget information is persisted when the widget is converted to a normal one ([onCastToNormalForm](../reference/apis/js-apis-app-form-formExtensionAbility.md#oncasttonormalform)). In addition, the persistent widget information needs to be deleted when the widget is destroyed ([onRemoveForm](../reference/apis/js-apis-app-form-formExtensionAbility.md#onremoveform)), preventing the database size from continuously increasing due to repeated widget addition and deletion.