song does not fast forward on slider drag iOS - ios

Question

I am implementing an audio player. It works fine but the slider drag does not update the song. The song starts from the start instead of being fast forward.
/*
* Updates the time label display and
* the current value of the slider
* while audio is playing
*/
- (void)updateTime:(NSTimer *)timer {
//to don't update every second. When scrubber is mouseDown the the slider will not set
NSLog(#"slider = %f",self.currentTimeSlider.value);
long currentPlaybackTime = [self.audioPlayer getCurrentAudioTime];
// self.currentTimeSlider.value = currentPlaybackTime / [self.audioPlayer getAudioDuration];
if ((currentPlaybackTime / [self.audioPlayer getAudioDuration]) > self.currentTimeSlider.value )
{
self.currentTimeSlider.value = currentPlaybackTime / [self.audioPlayer getAudioDuration];
self.timeElapsed.text = [NSString stringWithFormat:#"%#",
[self.audioPlayer timeFormat:[self.audioPlayer getCurrentAudioTime]]];
self.duration.text = [NSString stringWithFormat:#"%#",
[self.audioPlayer timeFormat:[self.audioPlayer getAudioDuration] - [self.audioPlayer getCurrentAudioTime]]];
}
else{
//self.currentTimeSlider.value = currentPlaybackTime / [self.audioPlayer getAudioDuration];
NSLog(#"sliderValuessszz = %f",self.currentTimeSlider.value);
NSLog(#"audio time = %f",[self.audioPlayer getCurrentAudioTime]);
self.timeElapsed.text = [NSString stringWithFormat:#"%#",
[self.audioPlayer timeFormat:[self.audioPlayer getCurrentAudioTime]]];
NSLog(#"time elapsed = %d",self.timeElapsed.text);
self.duration.text = [NSString stringWithFormat:#"%#",
[self.audioPlayer timeFormat:[self.audioPlayer getAudioDuration] - [self.audioPlayer getCurrentAudioTime]]];
}
}
- (IBAction)sliderChanged:(id)currentTimeSlider
{
NSLog(#"sliderValue = %f",self.currentTimeSlider.value);
NSLog(#"sliderValuesss = %f",self.currentTimeSlider.value);
//[self.timer invalidate];
[self.audioPlayer setCurrentAudioTime:self.currentTimeSlider.value];
[NSTimer scheduledTimerWithTimeInterval:0.01
target:self
selector:#selector(updateTime:)
userInfo:nil
repeats:NO];
/*if (!self.isPaused){
[self.audioPlayer stopAudio];
[self.audioPlayer setCurrentAudioTime:self.currentTimeSlider.value];
[self.audioPlayer prepareToPlayAudio];
[self.audioPlayer playAudio];
}
else
{
[self.audioPlayer setCurrentAudioTime: self.currentTimeSlider.value];
}
*/
}
On slider drag the song starts from beginning and timer label also shows the start time. Can someone please help me solve this.
Thanks,

Answer 1

Your MyAudioPlayer.h
#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
#interface MyAudioPlayer : UIViewController
#property (nonatomic, retain) AVAudioPlayer *audioPlayer;
// Public methods
- (void)initPlayer:(NSString*) audioFile fileExtension:(NSString*)fileExtension;
- (void)playAudio;
- (void)pauseAudio;
- (void)setCurrentAudioTime:(float)value;
- (float)getAudioDuration;
- (NSString*)timeFormat:(float)value;
- (NSTimeInterval)getCurrentAudioTime;
#end
the corresponding .m file
#implementation MyAudioPlayer
/*
* Init the Player with Filename and FileExtension
*/
- (void)initPlayer:(NSString*) audioFile fileExtension:(NSString*)fileExtension
{
NSURL *audioFileLocationURL = [[NSBundle mainBundle] URLForResource:audioFile withExtension:fileExtension];
NSError *error;
self.audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:audioFileLocationURL error:&error];
}
/*
* Simply fire the play Event
*/
- (void)playAudio {
[self.audioPlayer play];
}
/*
* Simply fire the pause Event
*/
- (void)pauseAudio {
[self.audioPlayer pause];
}
/*
* Format the float time values like duration
* to format with minutes and seconds
*/
-(NSString*)timeFormat:(float)value{
float minutes = floor(lroundf(value)/60);
float seconds = lroundf(value) - (minutes * 60);
int roundedSeconds = lroundf(seconds);
int roundedMinutes = lroundf(minutes);
NSString *time = [[NSString alloc]
initWithFormat:#"%d:%02d",
roundedMinutes, roundedSeconds];
return time;
}
/*
* To set the current Position of the
* playing audio File
*/
- (void)setCurrentAudioTime:(float)value {
[self.audioPlayer setCurrentTime:value];
}
/*
* Get the time where audio is playing right now
*/
- (NSTimeInterval)getCurrentAudioTime {
return [self.audioPlayer currentTime];
}
/*
* Get the whole length of the audio file
*/
- (float)getAudioDuration {
return [self.audioPlayer duration];
}
#end
the init method:
self.audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:audioFileLocationURL error:&error];
the view controller class
#import "MyAudioPlayer.h"
#interface ViewController : UIViewController
#property (nonatomic, strong) YMCAudioPlayer *audioPlayer;
#property (weak, nonatomic) IBOutlet UISlider *currentTimeSlider;
#property (weak, nonatomic) IBOutlet UIButton *playButton;
#property (weak, nonatomic) IBOutlet UILabel *duration;
#property (weak, nonatomic) IBOutlet UILabel *timeElapsed;
#property BOOL isPaused;
#property BOOL scrubbing;
#property NSTimer *timer;
#end
ViewController.m
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
self.audioPlayer = [[MyAudioPlayer alloc] init];
[self setupAudioPlayer:#"audiofile"];
}
/*
* Setup the AudioPlayer with
* Filename and FileExtension like mp3
* Loading audioFile and sets the time Labels
*/
- (void)setupAudioPlayer:(NSString*)fileName
{
//insert Filename & FileExtension
NSString *fileExtension = #"mp3";
//init the Player to get file properties to set the time labels
[self.audioPlayer initPlayer:fileName fileExtension:fileExtension];
self.currentTimeSlider.maximumValue = [self.audioPlayer getAudioDuration];
//init the current timedisplay and the labels. if a current time was stored
//for this player then take it and update the time display
self.timeElapsed.text = #"0:00";
self.duration.text = [NSString stringWithFormat:#"-%#",
[self.audioPlayer timeFormat:[self.audioPlayer getAudioDuration]]];
}
/*
* PlayButton is pressed
* plays or pauses the audio and sets
* the play/pause Text of the Button
*/
- (IBAction)playAudioPressed:(id)playButton
{
[self.timer invalidate];
//play audio for the first time or if pause was pressed
if (!self.isPaused) {
[self.playButton setBackgroundImage:[UIImage imageNamed:#"audioplayer_pause.png"]
forState:UIControlStateNormal];
//start a timer to update the time label display
self.timer = [NSTimer scheduledTimerWithTimeInterval:1.0
target:self
selector:#selector(updateTime:)
userInfo:nil
repeats:YES];
[self.audioPlayer playAudio];
self.isPaused = TRUE;
} else {
//player is paused and Button is pressed again
[self.playButton setBackgroundImage:[UIImage imageNamed:#"audioplayer_play.png"]
forState:UIControlStateNormal];
[self.audioPlayer pauseAudio];
self.isPaused = FALSE;
}
}
/*
* Updates the time label display and
* the current value of the slider
* while audio is playing
*/
- (void)updateTime:(NSTimer *)timer {
//to don't update every second. When scrubber is mouseDown the the slider will not set
if (!self.scrubbing) {
self.currentTimeSlider.value = [self.audioPlayer getCurrentAudioTime];
}
self.timeElapsed.text = [NSString stringWithFormat:#"%#",
[self.audioPlayer timeFormat:[self.audioPlayer getCurrentAudioTime]]];
self.duration.text = [NSString stringWithFormat:#"-%#",
[self.audioPlayer timeFormat:[self.audioPlayer getAudioDuration] - [self.audioPlayer getCurrentAudioTime]]];
}
/*
* Sets the current value of the slider/scrubber
* to the audio file when slider/scrubber is used
*/
- (IBAction)setCurrentTime:(id)scrubber {
//if scrubbing update the timestate, call updateTime faster not to wait a second and dont repeat it
[NSTimer scheduledTimerWithTimeInterval:0.01
target:self
selector:#selector(updateTime:)
userInfo:nil
repeats:NO];
[self.audioPlayer setCurrentAudioTime:self.currentTimeSlider.value];
self.scrubbing = FALSE;
}
/*
* Sets if the user is scrubbing right now
* to avoid slider update while dragging the slider
*/
- (IBAction)userIsScrubbing:(id)sender {
self.scrubbing = TRUE;
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end
self.audioPlayer = [[MyAudioPlayer alloc] init];
setUpAudioPlayer
self.timeElapsed.text = #"0:00";
self.duration.text = [NSString stringWithFormat:#"-%#",
[self.audioPlayer timeFormat:[self.audioPlayer getAudioDuration]]];
UpdateTime
- (void)updateTime:(NSTimer *)timer {
//to don't update every second. When scrubber is mouseDown the the slider will not set
if (!self.scrubbing) {
self.currentTimeSlider.value = [self.audioPlayer getCurrentAudioTime];
}
self.timeElapsed.text = [NSString stringWithFormat:#"%#",
[self.audioPlayer timeFormat:[self.audioPlayer getCurrentAudioTime]]];
self.duration.text = [NSString stringWithFormat:#"-%#",
[self.audioPlayer timeFormat:[self.audioPlayer getAudioDuration] - [self.audioPlayer getCurrentAudioTime]]];
}
Reference