book

Native Mobile Development

by Shaun Lewis, Mike Dunn

November 2019

Intermediate to advanced

394 pages

9h 44m

English

O'Reilly Media, Inc.

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Why We Wrote This BookWho This Book Is ForHow This Book Is OrganizedConventions Used in This BookUsing Code ExamplesO’Reilly Online LearningHow to Contact UsAcknowledgments
A Note About the State of Mobile Development
TasksAndroidHow to Create Your App’s Starting UI ControllerHow to Change the Active UI ControllerUnderstanding the UI Controller Life CycleiOSHow to Create Your App’s Starting UI ControllerHow to Change the Active UI ControllerUnderstanding the Controller Life CycleWhat We’ve Learned
TasksAndroidCreate a New ViewNesting ViewsUpdate a View’s StateiOSCreate a New ViewNesting ViewsInterface Builder to the RescueUpdate a View’s StateModifying PositionWhat We’ve Learned
TasksAndroidHow to Create a Custom ViewHow to Use a Custom ViewiOSHow to Create a Custom ViewHow to Use a Custom ViewWhat We’ve Learned
TasksAndroidReceive and React to a TapReceive and React to Keyboard InputHandle Compound GesturesiOSReceive and React to a TapReceive and React to Keyboard InputHandle Compound GesturesWhat We’ve Learned
TasksAndroidUse a Callback to React to an OperationDispatch a Message to Any Interested SubscribersListen for, and React to, Messages Dispatched Within a SystemiOSUse a Callback to React to an OperationDispatch a Message to Any Interested SubscribersListen for, and React to, Messages Dispatched Within a SystemClosures Instead of SelectorsStop Listening for NotificationsWhat We’ve Learned
TasksAndroidGet Properties from the File Like Size or Last Modified DateRead and Write Data to and from a FileCopy Data from One File to AnotheriOSGet Properties from the File Like Size or Last Modified DateReading and Writing Data to and from a FileCopy Data from One File to AnotherWhat We’ve Learned
TasksAndroidEstablish a Database ConnectionCreate a Database Table or Persistent ObjectWrite Data to That Table or Persistent ObjectRead Data from That Table or Persistent ObjectiOSSet Up and Connect to a Persistence LayerDefine and Create a Database Table or Persistent ObjectWrite and Persist Data to SQLiteRead Data from SQLiteWhat We’ve Learned
TasksAndroidPerform a Task in a Background ThreadAct on the Results of Work Performed in the Background Thread on the Main ThreadTerminating a ThreadiOSPerform a Task in a Background ThreadAct on the Results of Work Performed in the Background Thread on the Main ThreadWhat We’ve Learned

TasksAndroidRead and Print a Text File on a Remote ServerMake an HTTP POST RequestDownload a Binary FileiOSRead and Print a Text File on a Remote ServerMake an HTTP POST RequestDownload a Binary FileWhat We’ve Learned
TasksAndroidUse Framework-Provided Tools to Show the User FeedbackSnackbarUpdate the Status BariOSUse Framework-Provided Tools to Show the User FeedbackUpdate the Status BarWhat We’ve Learned
TasksAndroidWrite User PreferencesRead User PreferencesWork with User Preferences in a Multiple User ApplicationiOSWrite User PreferencesRead User PreferencesWork with User Preferences in a Multiple User ApplicationWhat We’ve Learned
TasksAndroidSerialize and Deserialize an Object InstanceiOSSerialize and Deserialize an Object InstanceiOS NotesWhat We’ve Learned
TasksAndroidAdd Functionality to Existing APIsiOSAdd Functionality to Existing APIsWhat We’ve Learned
TasksAndroidSet Up and Run Unit TestsSet Up and Run Integration TestsiOSSet Up and Run Unit TestsWhat We’ve Learned
Comparing Native Development to Cross-Platform ToolsWeb-BasedOtherEnvironment SetupAndroid SetupiOS SetupWhat We’ve Learned
Creating a New ProjectAndroid StudioXcodeApp ArchitectureBuilding Our First ScreenAndroidiOSWhat We’ve Learned
Sprucing Up ViewsAndroidiOSAdding a ButtoniOSLists, Lists, and More Lists!Add a New Catalog ViewWiring Up the ButtonBooksPopulating the List ViewAndroidiOSWhat We’ve Learned
Dynamic Data in List ViewsAndroidiOSIt’s Time for Our Model Objects to Get RealJSON for One, JSON for AllSwitch the Model Layer to JSONAndroidiOSWhat We’ve Learned
Detailing Our BooksAndroidiOSSaving Books for LaterAndroidiOSStoring Books for LaterAndroidiOSSaving BooksAndroidWhat We’ve Learned
Searching the WorldAndroidiOSBuilding a Search EndpointInstalling Node and ExpressLocations JSON FileCalling Our ServiceAndroidiOSWhat We’ve Learned

Content preview from Native Mobile Development

Chapter 6. Files

As a developer, you might want to read, write, or inspect a file for any number of reasons. For example, you might want to modify an image and save it to disk, download a video to your user’s SD card (after determining if one is available), or use a simple indexed JSON flat-file database. File handling logic comes up frequently in application development, so a good grasp of the fundamentals is important for most developers.

Tasks

In this chapter, you’ll learn to:

Get properties from a file like size on disk or last modified date.
Read and write data to and from a file.
Copy data from one file to another.

Android

In Android, a developer might query the device for the location of an external SD on the device, compress a group of files for upload, write XML to track user preferences, get bitmaps from assets, read a resource file, or log out events in a persistent fashion. Even an SQLite database (the AOSP framework–provided database) exists as a single file, so you’d use the same logic to determine its size, or make a duplicate for export.

Reading and writing files in Java has come a long way, and modern versions of the language include streaming APIs, an updated package called java.nio.file (“nio” means “new input/output”), and some handy helper classes like Files and Paths that offer a variety of approaches to file system access. Unfortunately, these are not available to most Android developers, and at the time of this writing, only the most recent two ...