Software Engineer Snippet

  return MaterialApp ( theme: ThemeData . dark ().copyWith(     textSelectionColor: [Color] ,  

  Change by: focusedBorder: UnderlineInputBorder (borderSide: BorderSide (color: keyColor)) , ) , return TextField ( autofocus: true, controller: control , decoration: InputDecoration ( hintText: txt , hintStyle: TextStyle (color: keyColor.withOpacity( 0.5 )) , focusedBorder: UnderlineInputBorder (borderSide: BorderSide (color: keyColor)) , ) , onChanged: func , ) ; } } //you can alse change the focusColor:

 if you delete packages "accidently",and you want it in the future. then you find out why .yaml doesn't work... haha  download the package version. for ex:  https://pub.dev/packages/admob_flutter/versions   put inside below location: (show hided files by press :  command + shift + .   )   Users>[your username]>Developor>flutter>.pub-cache>hosted>pub.dartlang.org

 20200806 下載flutter SDK 解壓後 ，我是將移至/usr/local 1.配置$PATH, 更新/etc/paths: cd /etc sudo nano paths 2.輸入存放flutter的bin的位置: /usr/local/flutter/bin control+ O (儲存)  control+x (離開) 4. 確認flutter指令可運作:which flutter  5.到App Store安裝Xcode這邊就不教了，可透過指令配置到最新版本: sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer sudo xcodebuild -runFirstLaunch 6.xcode license簽個同意書就完成了: sudo xcodebuild -license agree (7.可不裝…)

20210609 stackoverview   "http ? coverted to 3%F in url" var queryParameters = { 'q' : cityName, 'appid' : 'b6907d289e10d714a6e88b30761fae22' , }; var uri = Uri .http( 'samples.openweathermap.org' , '/data/2.5/forecast' , queryParameters);

 2021-05-31 stackoverflow step1 step2 step3 post_install do |installer| installer.pods_project.targets.each do |target| flutter_additional_ios_build_settings(target) target.build_configurations.each do |config| config.build_settings[ 'IPHONEOS_DEPLOYMENT_TARGET' ] = '9.0' end end end or post_install do |installer| installer.pods_project.targets.each do |target| target.build_configurations.each do |config| config.build_settings.delete 'IPHONEOS_DEPLOYMENT_TARGET' end end end step4 其實新版的沒這問題…

20201011   https://pub.dev/packages/admob_flutter   Firebase build.gradle classpath 'com.google.gms:google-services:4.3.4' app>src>build.gradle apply plugin : 'com.google.gms.google-services' implementation platform( 'com.google.firebase:firebase-bom:25.12.0' ) implementation  'com.google.firebase:firebase-analytics'                                                                                                                                                         Admob-Android app>src>main>AndroidManifest.xml <application android :name ="io.flutter.app.FlutterApplication" ...

20201011   Flexible( child: Text()),

  Firebase build.gradle classpath 'com.google.gms:google-services:4.3.4' app>src>build.gradle apply plugin : 'com.google.gms.google-services' implementation platform( 'com.google.firebase:firebase-bom:25.12.0' ) implementation  'com.google.firebase:firebase-analytics'                                                                                                                                                         Admob-Android app>src>main>AndroidManifest.xml <application android :name ="io.flutter.app.FlutterApplication" android :label ="keys" android :icon ="@mipmap/ic...

   20201011   iOS < key > NSFaceIDUsageDescription </ key > < string > Why is my app authenticating using face id? </ string >                                                                                                                                                                       Android Android -Trouble Error: PlatformException(no_fragment_activity, local_auth plugin requires activity to be a FragmentActivity., null) Trouble shotting: app>src>main>kotlin>[bundle id]> MainActivity.kt   package co.et.keys impo...

package co.et.keys import androidx.annotation.NonNull ; import io.flutter.embedding.android.FlutterFragmentActivity import io.flutter.embedding.engine.FlutterEngine import io.flutter.plugins.GeneratedPluginRegistrant class MainActivity: FlutterFragmentActivity() { override fun configureFlutterEngine(@NonNull flutterEngine: FlutterEngine) { GeneratedPluginRegistrant.registerWith(flutterEngine) ; } } <uses-permission android :name ="android.permission.USE_BIOMETRIC" /> refer 1 refer2  

void main () => runApp( MyApp ()) ; class MyApp extends StatelessWidget { @override Widget build (BuildContext context) { SystemChrome. setPreferredOrientations ( [DeviceOrientation. landscapeLeft , DeviceOrientation. landscapeRight ]) ;

 20200921 pod repo update sudo gem install cocoapods pod setup

20200920   1.app /  build.gradle defaultConfig  defaultConfig { applicationId "co.yourName.appName" 2.app/src/main/ AndroidManifest.xml  3.app/src/debug/ AndroidManifest.xml   4.app/src/profile/ AndroidManifest.xml   <manifest xmlns: android ="http://schemas.android.com/apk/res/android" package ="co.yourName.appName" > 5. app/main/kotlin/ co/yourName/ newName  6.app/main/kotlin/ co/ yourName / newName/  MainActivity.java   package co.yourName.appName ; 7.pubspec.yaml name : appName 8. lib all dart file  change appName 9.Runner.xcodeproj  /  project.pbxproj    (there are 3  PRODUCT_BUNDLE_IDENTIFIER ) must be changed.) PRODUCT_BUNDLE_IDENTIFIER = co.yourName.appName; 10. terminal  flutter clean 11. File >Invalidate Caches/Restart... 👍done

class _WelcomeScreenState extends State<WelcomeScreen> with SingleTickerProviderStateMixin { AnimationController controller ; Animation animation ; @override void initState () { super .initState() ; controller = AnimationController ( duration: Duration (seconds: 1 ) , //0 to 1 in 60 steps tickers. vsync: this, //SingleTickerProviderStateMixin class is going to provide animation Ticker // upperBound: 100.0,有curve class必須小於1，以避免衝突 ) ; animation = CurvedAnimation ( parent: controller , curve: Curves. easeIn ) ; //upperBound 需小於1 controller .forward() ; //Get the animation to start. proceed the animation forward(small to big) controller .addStatusListener((status) { if (status == AnimationStatus. completed ) { controller .reverse(from: 1.0 ) ;//值由小到大 } else if (status == AnimationStatus. dismissed ) { controller .forward() ; } print( animation . status ) ; }) ; //Ca...

environment sdk 改成2.6.0 後，重啟就不會出現錯誤了。 environment : sdk : ">=2.8.0 <3.0.0" items: [ for ( var i in currenciesList) DropdownMenuItem ( child: Text ( ' $i ' ) , value: ' $i ' , )], 

import 'package:flutter/material.dart' ; import 'package:audioplayers/audio_cache.dart' ; void main () => runApp( XylophoneApp ()) ; class XylophoneApp extends StatelessWidget { void audioPlayer (int musicNum) { final player = AudioCache () ; player.play( 'note $musicNum .wav' ) ; } Expanded keyboard ({Color color , int musicNum}) { return Expanded ( child: FlatButton ( color: color , onPressed: () { audioPlayer(musicNum) ; } , ) , ) ; } @override Widget build (BuildContext context) { return MaterialApp ( debugShowCheckedModeBanner: false, home: Scaffold ( body: SafeArea ( child: Center ( child: Column ( crossAxisAlignment: CrossAxisAlignment. stretch , children: [ keyboard(color: Colors. red , musicNum: 1 ) , keyboard(color: Colors. orange , musicNum: 2 ) , keyboard...