Saved Games In Unity Games - Android Developers

This topics describes how to use saved games for Play Games Services in Unity games.

Before you start

• Set up your project and the Google Play Games plugin for Unity. For details, see the Get started guide.

• Enabled saved games. See the saved games for details.

Display the saved games UI

The standard UI for selecting or creating a saved game entry is displayed by calling:

voidShowSelectUI(){ uintmaxNumToDisplay=5; boolallowCreateNew=false; boolallowDelete=true; ISavedGameClientsavedGameClient=PlayGamesPlatform.Instance.SavedGame; savedGameClient.ShowSelectSavedGameUI("Select saved game", maxNumToDisplay, allowCreateNew, allowDelete, OnSavedGameSelected); } publicvoidOnSavedGameSelected(SelectUIStatusstatus,ISavedGameMetadatagame){ if(status==SelectUIStatus.SavedGameSelected){ // handle selected game save }else{ // handle cancel or error } }

Open a saved game

In order to read or write data to a saved game, the saved game needs to be opened. Since the saved game state is cached locally on the device and saved to the cloud, it is possible to encounter conflicts in the state of the saved data. A conflict happens when a device attempts to save state to the cloud but the data currently on the cloud was written by a different device. These conflicts need to be resolved when opening the saved game data.

There are 2 open methods that handle conflict resolution, the first OpenWithAutomaticConflictResolution accepts a standard resolution strategy type and automatically resolves the conflicts. The other method, OpenWithManualConflictResolution accepts a callback method to allow the manual resolution of the conflict.

See ISavedGameClient for more details on these methods.

voidOpenSavedGame(stringfilename){ ISavedGameClientsavedGameClient=PlayGamesPlatform.Instance.SavedGame; savedGameClient.OpenWithAutomaticConflictResolution(filename,DataSource.ReadCacheOrNetwork, ConflictResolutionStrategy.UseLongestPlaytime,OnSavedGameOpened); } publicvoidOnSavedGameOpened(SavedGameRequestStatusstatus,ISavedGameMetadatagame){ if(status==SavedGameRequestStatus.Success){ // handle reading or writing of saved game. }else{ // handle error } }

Write a saved game

Once the saved game file is opened, it can be written to save the game state. This is done by calling CommitUpdate. There are four parameters to CommitUpdate:

1. the saved game metadata passed to the callback passed to one of the Open calls.
2. the updates to make to the metadata.
3. the actual byte array of data
4. a callback to call when the commit is complete.

voidSaveGame(ISavedGameMetadatagame,byte[]savedData,TimeSpantotalPlaytime){ ISavedGameClientsavedGameClient=PlayGamesPlatform.Instance.SavedGame; SavedGameMetadataUpdate.Builderbuilder=newSavedGameMetadataUpdate.Builder(); builder=builder .WithUpdatedPlayedTime(totalPlaytime) .WithUpdatedDescription("Saved game at "+DateTime.Now()); if(savedImage!=null){ // This assumes that savedImage is an instance of Texture2D // and that you have already called a function equivalent to // getScreenshot() to set savedImage // NOTE: see sample definition of getScreenshot() method below byte[]pngData=savedImage.EncodeToPNG(); builder=builder.WithUpdatedPngCoverImage(pngData); } SavedGameMetadataUpdateupdatedMetadata=builder.Build(); savedGameClient.CommitUpdate(game,updatedMetadata,savedData,OnSavedGameWritten); } publicvoidOnSavedGameWritten(SavedGameRequestStatusstatus,ISavedGameMetadatagame){ if(status==SavedGameRequestStatus.Success){ // handle reading or writing of saved game. }else{ // handle error } } publicTexture2DgetScreenshot(){ // Create a 2D texture that is 1024x700 pixels from which the PNG will be // extracted Texture2DscreenShot=newTexture2D(1024,700); // Takes the screenshot from top left hand corner of screen and maps to top // left hand corner of screenShot texture screenShot.ReadPixels( newRect(0,0,Screen.width,(Screen.width/1024)*700),0,0); returnscreenShot; }

Read a saved game

Once the saved game file is opened, it can be read to load the game state. This is done by calling ReadBinaryData.

voidLoadGameData(ISavedGameMetadatagame){ ISavedGameClientsavedGameClient=PlayGamesPlatform.Instance.SavedGame; savedGameClient.ReadBinaryData(game,OnSavedGameDataRead); } publicvoidOnSavedGameDataRead(SavedGameRequestStatusstatus,byte[]data){ if(status==SavedGameRequestStatus.Success){ // handle processing the byte array data }else{ // handle error } }

Delete a saved game

Once the saved game file is opened, it can be deleted. This is done by calling Delete.

voidDeleteGameData(stringfilename){ // Open the file to get the metadata. ISavedGameClientsavedGameClient=PlayGamesPlatform.Instance.SavedGame; savedGameClient.OpenWithAutomaticConflictResolution(filename,DataSource.ReadCacheOrNetwork, ConflictResolutionStrategy.UseLongestPlaytime,DeleteSavedGame); } publicvoidDeleteSavedGame(SavedGameRequestStatusstatus,ISavedGameMetadatagame){ if(status==SavedGameRequestStatus.Success){ ISavedGameClientsavedGameClient=PlayGamesPlatform.Instance.SavedGame; savedGameClient.Delete(game); }else{ // handle error } }