capDriverConnect(hCapWnd, 0);
capDlgVideoFormat(hCapWnd); //會出現「視訊各式」的視窗
或是用Excel開啟文件，出現檔案格式不相符的訊息
會指定儲存工作表時的檔案格式。
| 名稱 | 值 | 描述 | 副檔名 |
|---|---|---|---|
| xlAddIn | 18 | Microsoft Excel 97-2003 增益集 | *.xla |
| xlAddIn8 | 18 | Microsoft Excel 97-2003 增益集 | *.xla |
| xlCSV | 6 | CSV | *.csv |
| xlCSVMac | 22 | Macintosh CSV | *.csv |
| xlCSVMSDOS | 24 | MSDOS CSV | *.csv |
| xlCSVUTF8 | 62 | UTF8 CSV | *.csv |
| xlCSVWindows | 至 | Windows CSV | *.csv |
| xlCurrentPlatformText | -4158 | 目前平台文字 | *.txt |
| xlDBF2 | 7 | Dbase 2 格式 | *.dbf |
| xlDBF3 | 8 | Dbase 3 格式 | *.dbf |
| xlDBF4 | 11 | Dbase 4 格式 | *.dbf |
| xlDIF | 9 | 資料交換格式 | *.dif |
| xlExcel12 | 50 | Excel 二進位活頁簿 | *.xlsb |
| xlExcel2 | 16 | Excel 2.0 版 (1987) | *.xls |
| xlExcel2FarEast | 7 | Excel 2.0 遠東版 (1987) | *.xls |
| xlExcel3 | 29 | Excel 3.0 版 (1990) | *.xls |
| xlExcel4 | 33 | Excel 4.0 版 (1992) | *.xls |
| xlExcel4Workbook | 35 | Excel 4.0 版 活頁簿格式 (1992) | *.xlw |
| xlExcel5 | 39 | Excel 5.0 版 (1994) | *.xls |
| xlExcel7 | 39 | Excel 95 (7.0 版) | *.xls |
| xlExcel8 | 56 | Excel 97-2003 活頁簿 | *.xls |
| xlExcel9795 | 43 | Excel 95 與 97 版 | *.xls |
| xlHtml | 44 | HTML 格式 | .htm；.html |
| xlIntlAddIn | 得到 | 國際增益集 | 沒有副檔名 |
| xlIntlMacro | 0.25 | 國際巨集 | 沒有副檔名 |
| xlOpenDocumentSpreadsheet | 60 | OpenDocument 試算表 | *.ods |
| xlOpenXMLAddIn | 55 | 開啟 XML 增益集 | *.xlam |
| xlOpenXMLStrictWorkbook | 61 (&H3D) | Strict Open XML 檔案 | *.xlsx |
| xlOpenXMLTemplate | 54 | 開啟 XML 範本 | *.xltx |
| xlOpenXMLTemplateMacroEnabled | 53 | 開啟 Open XML 範本巨集啟用 | *.xltm |
| xlOpenXMLWorkbook | 51 | 開啟 XML 活頁簿 | *.xlsx |
| xlOpenXMLWorkbookMacroEnabled | 52 | 開啟 XML 活頁簿巨集啟用 | *.xlsm |
| xlSYLK | 第 | 符號連結格式 | *.slk |
| xlTemplate | 17 | Excel 範本格式 | *.xlt |
| xlTemplate8 | 17 | 範本 8 | *.xlt |
| xlTextMac | 19 | Macintosh 文字 | *.txt |
| xlTextMSDOS | 21 | MSDOS 文字 | *.txt |
| xlTextPrinter | 36 | 印表機文字 | *.prn |
| xlTextWindows | 共 | Windows 文字 | *.txt |
| xlUnicodeText | 42 | Unicode 文字 | 沒有副檔名；*.txt |
| xlWebArchive | 45 | Web 封存 | .mht；.mhtml |
| xlWJ2WD1 | 14 | 日文 1-2-3 | *.wj2 |
| xlWJ3 | 40 | 日文 1-2-3 | *.wj3 |
| xlWJ3FJ3 | 41 | 日文 1-2-3 格式 | *.wj3 |
| xlWK1 | 5 | Lotus 1-2-3 格式 | *.wk1 |
| xlWK1ALL | 加 | Lotus 1-2-3 格式 | *.wk1 |
| xlWK1FMT | 大約 | Lotus 1-2-3 格式 | *.wk1 |
| xlWK3 | 15 | Lotus 1-2-3 格式 | *.wk3 |
| xlWK3FM3 | 32 | Lotus 1-2-3 格式 | *.wk3 |
| xlWK4 | 38 | Lotus 1-2-3 格式 | *.wk4 |
| xlWKS | 4 | Lotus 1-2-3 格式 | *.wks |
| xlWorkbookDefault | 51 | 預設活頁簿 | *.xlsx |
| xlWorkbookNormal | -4143 | 一般活頁簿 | *.xls |
| xlWorks2FarEast | 日 | Microsoft Works 2.0 遠東格式 | *.wks |
| xlWQ1 | 34 | Quattro Pro 格式 | *.wq1 |
| xlXMLSpreadsheet | 46 | XML 試算表 | *.xml |
import 'package:flutter/material.dart';
class dropdownButton extends StatefulWidget {
@override
_dropdownButtonState createState() => _dropdownButtonState();
}
class _dropdownButtonState extends State<dropdownButton> {
List<DropdownMenuItem<String>> listDrop = [];
String selected = "1";
void loadData() {
listDrop = [];
listDrop.add(DropdownMenuItem(child: Text("item 1"), value: "1"));
listDrop.add(DropdownMenuItem(child: Text("item 2"), value: "2"));
listDrop.add(DropdownMenuItem(child: Text("item 3"), value: "3"));
listDrop.add(DropdownMenuItem(child: Text("item 4"), value: "4"));
listDrop.add(DropdownMenuItem(child: Text("item 5"), value: "5"));
}
@override
Widget build(BuildContext context) {
loadData();
return Scaffold(
body: Center(
child: Column(children: [
DropdownButton(
dropdownColor: Colors.amber,
style: TextStyle(color: Colors.white,),
icon: Icon(Icons.arrow_drop_down_circle),
elevation: 36,
items: listDrop,
value: selected,
hint: Text("Select item..."),
onChanged: (String? newValue) {
setState(() {
selected = newValue!;
});
},
),
]),
));
}
}
import 'package:flutter/material.dart';
import 'package:untitled/Constants.dart';
class dropdownButton extends StatefulWidget {
@override
_dropdownButtonState createState() => _dropdownButtonState();
}
class _dropdownButtonState extends State<dropdownButton> {
List<DropdownMenuItem<String>> listDrop = [];
String selected = "1";
void loadData() {
listDrop = [];
listDrop.add(DropdownMenuItem(child: Text("item 1"), value: "1"));
listDrop.add(DropdownMenuItem(child: Text("item 2"), value: "2"));
listDrop.add(DropdownMenuItem(child: Text("item 3"), value: "3"));
listDrop.add(DropdownMenuItem(child: Text("item 4"), value: "4"));
listDrop.add(DropdownMenuItem(child: Text("item 5"), value: "5"));
}
@override
Widget build(BuildContext context) {
loadData();
void Function() Button_OnClick = () {
Navigator.pop(context);
};
return Scaffold(
backgroundColor: appGreyColor,
body: Center(
child: Column(children: [
DropdownButtonFormField(
decoration: InputDecoration(
icon: Icon(Icons.bug_report),
labelText: "Select item...",
labelStyle: TextStyle(
color: Colors.black,
),
contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(32.0),
),
hintStyle: TextStyle(
color: Colors.white,
),
),
style: TextStyle(
color: Colors.white,
),
items: listDrop,
onChanged: (String? newValue) {
setState(() {
selected = newValue!;
});
},
dropdownColor: appBackgroundGreyColor,
icon: Icon(Icons.arrow_drop_down_circle, color: Colors.white,),
),
]),
));
}
}
warning: [deprecation] get(int,int) in CamcorderProfile has been deprecated 排除
截錄:
Error: Cannot run with sound null safety, because the following dependencies
Copy: --no-sound-null-safety
添加相關依賴套件 （dependencies）
dependencies:
flutter:
sdk: flutter
camera:
path_provider:
path:
根據 Flutter 官方教學文件
Tip:
minSdkVersion to 21 (or higher).ios/Runner/Info.plist in order the access the camera.<key>NSCameraUsageDescription</key>
<string>Explanation on why the camera access is needed.</string>minSdkVersion 必須在21以上
為了解決這個問題，我們必須修改 Flutter 專案中 Android 的最低 SDK 版本。
在 Flutter 專案中，我們要修改的文件路徑為 PROJECT_NAME/android/app/build.gradle
def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
localPropertiesFile.withReader('UTF-8') { reader ->
localProperties.load(reader)
}
}
def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}
def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
flutterVersionCode = '1'
}
def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
flutterVersionName = '1.0'
}
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
android {
compileSdkVersion flutter.compileSdkVersion
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
kotlinOptions {
jvmTarget = '1.8'
}
sourceSets {
main.java.srcDirs += 'src/main/kotlin'
}
defaultConfig {
// TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
applicationId "com.example.untitled"
minSdkVersion 21 //flutter.minSdkVersion
targetSdkVersion 30 //flutter.targetSdkVersion
versionCode flutterVersionCode.toInteger()
versionName flutterVersionName
}
buildTypes {
release {
// TODO: Add your own signing config for the release build.
// Signing with the debug keys for now, so `flutter run --release` works.
signingConfig signingConfigs.debug
}
}
}
flutter {
source '../..'
}
dependencies {
implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
}
將minSdkVersion 修改為 21（或任何你需要的版本號）
import 'package:flutter/material.dart';
import 'package:untitled1/TakePictureScreen.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: _mainbody(),
),
);
}
}
class _mainbody extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Center(
child: RaisedButton(
child: Text("Camera"),
onPressed: () {
takePictureScreen_main();
},
),
);
}
}
import 'dart:async';
import 'dart:io';
import 'package:camera/camera.dart';
import 'package:flutter/material.dart';
Future<void> takePictureScreen_main() async {
// Ensure that plugin services are initialized so that `availableCameras()`
// can be called before `runApp()`
WidgetsFlutterBinding.ensureInitialized();
// Obtain a list of the available cameras on the device.
final cameras = await availableCameras();
// Get a specific camera from the list of available cameras.
final firstCamera = cameras.first;
runApp(
MaterialApp(
theme: ThemeData.dark(),
home: TakePictureScreen(
// Pass the appropriate camera to the TakePictureScreen widget.
camera: firstCamera,
),
),
);
}
// A screen that allows users to take a picture using a given camera.
class TakePictureScreen extends StatefulWidget {
const TakePictureScreen({
Key? key,
required this.camera,
}) : super(key: key);
final CameraDescription camera;
@override
TakePictureScreenState createState() => TakePictureScreenState();
}
class TakePictureScreenState extends State<TakePictureScreen> {
late CameraController _controller;
late Future<void> _initializeControllerFuture;
@override
void initState() {
super.initState();
// To display the current output from the Camera,
// create a CameraController.
_controller = CameraController(
// Get a specific camera from the list of available cameras.
widget.camera,
// Define the resolution to use.
ResolutionPreset.medium,
);
// Next, initialize the controller. This returns a Future.
_initializeControllerFuture = _controller.initialize();
}
@override
void dispose() {
// Dispose of the controller when the widget is disposed.
_controller.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Take a picture')),
// You must wait until the controller is initialized before displaying the
// camera preview. Use a FutureBuilder to display a loading spinner until the
// controller has finished initializing.
body: FutureBuilder<void>(
future: _initializeControllerFuture,
builder: (context, snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
// If the Future is complete, display the preview.
return CameraPreview(_controller);
} else {
// Otherwise, display a loading indicator.
return const Center(child: CircularProgressIndicator());
}
},
),
floatingActionButton: FloatingActionButton(
// Provide an onPressed callback.
onPressed: () async {
// Take the Picture in a try / catch block. If anything goes wrong,
// catch the error.
try {
// Ensure that the camera is initialized.
await _initializeControllerFuture;
// Attempt to take a picture and get the file `image`
// where it was saved.
final image = await _controller.takePicture();
// If the picture was taken, display it on a new screen.
await Navigator.of(context).push(
MaterialPageRoute(
builder: (context) => DisplayPictureScreen(
// Pass the automatically generated path to
// the DisplayPictureScreen widget.
imagePath: image.path,
),
),
);
} catch (e) {
// If an error occurs, log the error to the console.
print(e);
}
},
child: const Icon(Icons.camera_alt),
),
);
}
}
// A widget that displays the picture taken by the user.
class DisplayPictureScreen extends StatelessWidget {
final String imagePath;
const DisplayPictureScreen({Key? key, required this.imagePath})
: super(key: key);
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Display the Picture')),
// The image is stored as a file on the device. Use the `Image.file`
// constructor with the given path to display the image.
body: Image.file(File(imagePath)),
);
}
}
參考:
截錄 :