Purging Documents Directory in iOS

Your local sandboxed Documents directory may get stuffed with a bunch of garbage. To purge the directory and it's contents use this simple method:

- (void)purgeDocumentsDirectory

{

    NSLog(@"Purging Documents Directory...");

    NSString *folderPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];

    NSError *error = nil;

    for (NSString *file in [[NSFileManager defaultManager] contentsOfDirectoryAtPath:folderPath error:&error]) {

        [[NSFileManager defaultManager] removeItemAtPath:[folderPath stringByAppendingPathComponent:file] error:&error];

    }

}

Get substring from an NSString in Objective-C

In Objective-C / Cocoa to grab a substring from an NSString based on beginning and ending characters is easy. This is helpful if you want to parse HTML, JSON, or a REST statement returning. See below:

 NSString *sStr = [NSString stringWithFormat:@"%@", assetGroups[indexPath.row]];
 NSString *name= [[[[sStr componentsSeparatedByString:@"Beginning Char(s)"] objectAtIndex:1] componentsSeparatedByString:@"End Char(s)"] objectAtIndex:0]; 
 NSString *newString = [NSString stringWithFormat:@"%@", name];

Playing Music from iOS Music Playlist with Unity3D

With this simple coding you can play a playlist on your device from your Unity3D Game. Why license royalties when you can get the user to do it for you per individual basis.  I am using this in my game Snowboarding+ (see gameplay demo above). If there is no music on your device it'll finally play the local music in your Unity 3D app. This plays the playlist called Snowboarding+

in AppController.mm (also add MediaPlayer.framework):

#include <MediaPlayer/MediaPlayer.h>

- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions

{

[self playMusic];

}

- (void) playMusic {

  // Instantiate a music player

    MPMusicPlayerController *appPlayer = [MPMusicPlayerController applicationMusicPlayer];

    

    // Shuffle all songs

    [appPlayer setShuffleMode:MPMusicShuffleModeSongs];

    

    // Assume we will not find our playlist

    BOOL playlistFound = NO;

    

    // Get a collection of all playlists on the device

    MPMediaQuery *playlistsQuery = [MPMediaQuery playlistsQuery];

    NSArray *playlists = [playlistsQuery collections];

    NSString *plus;

    plus = @"all";

    // Check each playlist to see if it is the right one

    for (MPMediaPlaylist *playlist in playlists) {

        NSString *playlistName = [playlist valueForProperty: MPMediaPlaylistPropertyName];

        if ([playlistName isEqualToString:@"Snowboarding+"]) {

            // Add the playlist to the player's queue and get out of here

            [appPlayer setQueueWithItemCollection:playlist];

            playlistFound = YES;

            plus = @"snowboarding+";

            break;

        }

    }

    

    // If no playlist found, just play All playlist

    if (!playlistFound) {

        for (MPMediaPlaylist *playlist in playlists) {

            NSString *playlistName = [playlist valueForProperty: MPMediaPlaylistPropertyName];

            if ([playlistName isEqualToString:@"All"]) {

                // Add the playlist to the player's queue and get out of here

                [appPlayer setQueueWithItemCollection:playlist];

                playlistFound = YES;

                plus = @"all";

                break;

            }

            else

            {

                //IF NO ALL play a random song

                [appPlayer setQueueWithQuery: [MPMediaQuery songsQuery]];

                plus = @"random";

            }

        }

    }

    

    // Start playing from the beginning of the queue

    [appPlayer play];

    

    if (appPlayer.playbackState == MPMusicPlaybackStatePlaying)

{                

UnitySendMessage("Camera", "isPlaying","TRUE");

NSLog(@"%@ is playing",plus);}

            else

{

                UnitySendMessage("Camera", "isPlaying","FALSE");

NSLog(@"internal music from Unity3D App is playing");}

}

}

In Unity 3D add the following to the Script on your Camera or any game object from above:

var isMusicPlaying: boolean = false;

@script RequireComponent(AudioSource)

function Start() {

    // Delay a clip by 10 sec (44100 samples)

  #if UNITY_EDITOR || UNITY_ANDROID || UNITY_OSX

      audio.Play(44100 * 5);     

   #endif

}

function isPlaying(message:String)

 {

  if (message == "TRUE") {isMusicPlaying = true; audio.Stop(); }

  if (message == "FALSE") {isMusicPlaying = false;  audio.Play();  }

  Debug.Log("Is the Music Playing from Device? " + message);

 }

Player Movement for Simple Air Hockey Game

This segment is for simple movement for a player in an Air Hockey Game on a 3D plane. You move mouse x and y and the y corresponds on the z plane.  This is from my Air Hockey 3D game available currently in the Android, iOS and Mac App Stores.

var other : GameObject ;
var dist : float;
var hitSound : AudioClip;
var spark : Transform;
var offset : Vector2 = Vector2.zero;
function spark1()
{
Instantiate (spark, transform.position, transform.rotation);
yield WaitForSeconds(0.5);
Destroy(GameObject.Find("Sparks(clone)"));
}
function Update () {
if (Time.timeScale != 0) {
other = GameObject.Find ("Sphere");
var Menu = GameObject.Find("Menu");
var script : menu = Menu.GetComponent(menu);
  var hit : RaycastHit;  
    var up = Vector3 ((transform.position.x - other.transform.position.x) * -1 , 0,
    (transform.position.z - other.transform.position.z) * -1 );
 
    if (Input.GetAxis("Mouse Y") > 0)     dist = 0.3 +  (Input.GetAxis("Mouse Y") / 8 ) + other.rigidbody.velocity.magnitude / 80;   else
    dist = 0.15 + other.rigidbody.velocity.magnitude / 80;
 
   Debug.DrawRay(transform.position, up , Color.green);
 
    if(Physics.Raycast(transform.position, up , hit, dist)){
       
      if(hit.collider.gameObject.name == "Sphere"){
      spark1();
      AudioSource.PlayClipAtPoint(hitSound, transform.position);
      other.rigidbody.AddForce(  up * (other.rigidbody.velocity.magnitude + 20 ),  ForceMode.Impulse);
      }
    }
if (script.singlePlayer) {
Screen.showCursor = false; #if UNITY_EDITOR
if (Input.mousePosition.x >  0  &&  Input.mousePosition.x < Screen.width)
transform.position.x = Input.mousePosition.x / (Screen.width / 2.4);
if (Input.mousePosition.y >  0 && Input.mousePosition.y < (Screen.height * 0.7)) {
if (transform.position.z < 2.194 && transform.position.z > 0) {
transform.position.z =  (Input.mousePosition.y * 0.7) / ((Screen.height * 0.7) / (3.18));
}
else if (transform.position.z >= 2.194) transform.position.z = 2.193;
 else if (transform.position.z <= 0) transform.position.z = 0.0001;
}
//Debug.Log(transform.position.z);
#elif UNITY_IPHONE || UNITY_ANDROID
if(Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Moved) {
if (Input.mousePosition.x >  0  &&  Input.mousePosition.x < Screen.width)
transform.position.x = Input.mousePosition.x / (Screen.width / 2.4);
if (Input.mousePosition.y >  0 && Input.mousePosition.y < (Screen.height * 0.7)) {
if (transform.position.z < 2.194 && transform.position.z > 0) {
transform.position.z =  (Input.mousePosition.y * 0.7) / ((Screen.height * 0.7) / (3.18));
}
else if (transform.position.z >= 2.194) transform.position.z = 2.193;
 else if (transform.position.z <= 0) transform.position.z = 0.0001;
}
}
#endif
}
}
}