1# Updating Widget Content by State 2 3 4There are cases where multiple copies of the same widget are added to the home screen to accommodate different needs. In these cases, the widget content needs to be dynamically updated based on the state. This topic exemplifies how this is implemented. In the following example, two weather widgets are added to the home screen: one for displaying the weather of London, and the other Beijing, both configured to be updated at 07:00 every morning. The widget provider detects the target city, and then displays the city-specific weather information on the widgets. 5 6 7- Widget configuration file: Configure the widget to be updated at 07:00 every morning. 8 9 ```json 10 { 11 "forms": [ 12 { 13 "name": "widget", 14 "description": "This is a service widget.", 15 "src": "./ets/widget/pages/WidgetCard.ets", 16 "uiSyntax": "arkts", 17 "window": { 18 "designWidth": 720, 19 "autoDesignWidth": true 20 }, 21 "colorMode": "auto", 22 "isDefault": true, 23 "updateEnabled": true,"scheduledUpdateTime": "07:00", 24 "updateDuration": 0, 25 "defaultDimension": "2*2", 26 "supportDimensions": ["2*2"] 27 } 28 ] 29 } 30 ``` 31 32- 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. 33 34 ```ts 35 let storage = new LocalStorage(); 36 @Entry(storage) 37 @Component 38 struct WidgetCard { 39 @LocalStorageProp('textA') textA: string = 'To be updated...'; 40 @LocalStorageProp('textB') textB: string ='To be updated...'; 41 @State selectA: boolean = false; 42 @State selectB: boolean = false; 43 44 build() { 45 Column() { 46 Row() { 47 Checkbox({ name: 'checkbox1', group: 'checkboxGroup' }) 48 .select(false) 49 .onChange((value: boolean) => { 50 this.selectA = value; 51 postCardAction(this, { 52 'action': 'message', 53 'params': { 54 'selectA': JSON.stringify(value) 55 } 56 }); 57 }) 58 Text ('State A') 59 } 60 61 Row() { 62 Checkbox({ name: 'checkbox2', group: 'checkboxGroup' }) 63 .select(false) 64 .onChange((value: boolean) => { 65 this.selectB = value; 66 postCardAction(this, { 67 'action': 'message', 68 'params': { 69 'selectB': JSON.stringify(value) 70 } 71 }); 72 }) 73 Text ('State B') 74 } 75 76 Row() {// Content that is updated only in state A 77 Text ('State A:') 78 Text(this.textA) 79 } 80 81 Row() { // Content that is updated only in state B 82 Text ('State B:') 83 Text(this.textB) 84 } 85 }.padding('10%') 86 } 87 } 88 ``` 89 90- 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. 91 92 ```ts 93 import formInfo from '@ohos.app.form.formInfo' 94 import formProvider from '@ohos.app.form.formProvider'; 95 import formBindingData from '@ohos.app.form.formBindingData'; 96 import FormExtensionAbility from '@ohos.app.form.FormExtensionAbility'; 97 import dataStorage from '@ohos.data.storage' 98 99 export default class EntryFormAbility extends FormExtensionAbility { 100 onAddForm(want) { 101 let formId = want.parameters[formInfo.FormParam.IDENTITY_KEY]; 102 let isTempCard: boolean = want.parameters[formInfo.FormParam.TEMPORARY_KEY]; 103 if (isTempCard === false) {// If the widget is a normal one, the widget information is persisted. 104 console.info('Not temp card, init db for:' + formId); 105 let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore') 106 storeDB.putSync('A' + formId, 'false'); 107 storeDB.putSync('B' + formId, 'false'); 108 storeDB.flushSync(); 109 } 110 let formData = {}; 111 return formBindingData.createFormBindingData(formData); 112 } 113 114 onRemoveForm(formId) { 115 console.info('onRemoveForm, formId:' + formId); 116 let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore') 117 storeDB.deleteSync('A' + formId); 118 storeDB.deleteSync('B' + formId); 119 } 120 121 // 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. 122 onCastToNormalForm(formId) { 123 console.info('onCastToNormalForm, formId:' + formId); 124 let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore') 125 storeDB.putSync('A' + formId, 'false'); 126 storeDB.putSync('B' + formId, 'false'); 127 storeDB.flushSync(); 128 } 129 130 onUpdateForm(formId) { 131 let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore') 132 let stateA = storeDB.getSync('A' + formId, 'false').toString() 133 let stateB = storeDB.getSync('B' + formId, 'false').toString() 134 // Update textA in state A. 135 if (stateA === 'true') { 136 let formInfo = formBindingData.createFormBindingData({ 137 'textA': 'AAA' 138 }) 139 formProvider.updateForm(formId, formInfo) 140 } 141 // Update textB in state B. 142 if (stateB === 'true') { 143 let formInfo = formBindingData.createFormBindingData({ 144 'textB': 'BBB' 145 }) 146 formProvider.updateForm(formId, formInfo) 147 } 148 } 149 150 onFormEvent(formId, message) { 151 // Store the widget state. 152 console.info('onFormEvent formId:' + formId + 'msg:' + message); 153 let storeDB = dataStorage.getStorageSync(this.context.filesDir + 'myStore') 154 let msg = JSON.parse(message) 155 if (msg.selectA != undefined) { 156 console.info('onFormEvent selectA info:' + msg.selectA); 157 storeDB.putSync('A' + formId, msg.selectA); 158 } 159 if (msg.selectB != undefined) { 160 console.info('onFormEvent selectB info:' + msg.selectB); 161 storeDB.putSync('B' + formId, msg.selectB); 162 } 163 storeDB.flushSync(); 164 } 165 }; 166 ``` 167 168 169> **NOTE** 170> 171> 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. 172