i have created an app with music buttons.the app is running with no problem in the emulator of eclipse but as i use my samsung galaxy s for emulator i have a force down error as i press any button..this is my logcat when i press a btn:
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this is my code from 56-86 line
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v){
if(mp2.isPlaying()==true||mp3.isPlaying()==true||mp4.isPlaying()==true||mp5.isPlaying()==true||mp6.isPlaying()==true||mp7.isPlaying()==true||mp8.isPlaying()==true||mp9.isPlaying()==true||mp10.isPlaying()==true||mp11.isPlaying()==true||mp12.isPlaying()==true)
{mp2.stop();
mp3.stop();mp4.stop();mp5.stop();mp6.stop();mp7.stop();mp8.stop();mp9.stop();mp10.stop();mp11.stop();mp12.stop();
try {
mp2.prepare();
mp3.prepare();
mp4.prepare();
mp5.prepare();mp6.prepare();mp7.prepare();mp8.prepare();mp9.prepare();mp10.prepare();
mp11.prepare();mp12.prepare();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mp.start();
Toast.makeText(a.this, "Eisai", Toast.LENGTH_SHORT).show();
}
else
mp.start();
Toast.makeText(a.this, "Eisai sto myalo", Toast.LENGTH_SHORT).show();
}
});
Is your "if" statement line 58? (Assuming you've noted the line range correctly, it should be.) Set a debug breakpoint on that line, and inspect all of your mp* variables. Most likely one of them is null. As a side note, for clearer code, you might want to try using an ArrayList<MediaPlayer> to store all those MediaPlayer objects.
EDIT: You can find the ArrayList documentation here.
Basically:
List<MediaPlayer> mediaPlayers = new ArrayList<MediaPlayer>();
//I have no idea how you're currently making the MediaPlayers,
//so modify accordingly.
mediaPlayers.add(MediaPlayer.create(Context, Uri));
Then, you can just use something like:
public void stopAllIfPlaying(ArrayList<MediaPlayer> mps) {
for (MediaPlayer mp : mps) {
if(mp.isPlaying()) mp.stop();
}
}
And instead of your if statement and stop statements, use something like this:
stopAllIfPlaying(mediaPlayers);
Then do something similar with your prepare statements.
Next time when you post a stacktrace, what happens BEFORE the NPE is a lot better than what happens after... But it's pretty obvious that Button button = (Button) findViewById(R.id.btn1) is returning null. Make sure your XML is correct and there's actually a button there.
Related
So I put an audio file in my application and it's supposted play when I touch the button and stop when I touch it again.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button one = (Button) findViewById(R.id.buttonId);
final MediaPlayer mp = new MediaPlayer();
one.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
if(mp.isPlaying())
{
mp.stop();
}
try {
mp.reset();
AssetFileDescriptor afd;
afd = getAssets().openFd("mosq.mp3");
mp.setDataSource(afd.getFileDescriptor(),afd.getStartOffset(),afd.getLength());
mp.prepare();
mp.setLooping(true);
mp.start();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
});
here is my code, this part:
if(mp.isPlaying())
{
mp.stop();
}
didn't work for some reason.
Make sure you put a return statement below mp.stop().
From what I can understand the sound does stop but then it starts again because the next part of the code still gets executed
As George D correctly pointed out, you start the media playing unconditionally, even if you just stopped it. You could use his solution or do something like:
if(mp.isPlaying())
{
mp.stop();
}
else {
try {
mp.reset();
AssetFileDescriptor afd;
afd = getAssets().openFd("mosq.mp3");
mp.setDataSource(afd.getFileDescriptor(),afd.getStartOffset(),afd.getLength());
mp.prepare();
mp.setLooping(true);
mp.start();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
This has several other potential bugs in it:
* I'm not sure if this is what you intended but the player won't ever pause, just stop and restart from the beginning. If you try to resume or play again it'll completely reload the audio file every time. At a minimum this is a waste of resources, plus it's likely not the expected behavior from a UI perspective.
* You don't want to define the MediaPlayer object as a local variable within the OnCreate method. The only reason this works at all is you have a memory leak (you never unsubscribe your event handler for the click); if you didn't have the memory leak the object would become eligible for garbage collection as soon as you completed the onCreate method and, as far as the framework was concerned, it would no longer exist.
I have been trying to develop an Andriod app of a simple sound board, which will play several long sounds, and only one at a time, not simultaneously. I can easily do a soundboard that uses repetitive code and many mediaplayers, but that will likely crash many devices due to allocating too many instances of MediaPlayer. I want to use a map so that I only use one mediaplayer, but after several hours, I’m still having compile problems. I could also use the App Inventor at MIT, but I don’t think I could upload that to market place without extensive key/signing hacks, so I don’t think that is a good option.
Does anyone know if there a working code example with just a couple of sounds that use just 1 mediaplayer included with the SDK, or available online? If I could start with just a basic working design, it would save me so much time.
My code looks like the below:
public class newBoard extends Activity {
int selectedSoundId;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
*//below line causes an error due to use of "newboard"*
setContentView(R.layout.newboard);
final MediaPlayer player = new MediaPlayer();
final Resources res = getResources();
//just keep them in the same order, e.g. button01 is tied to backtoyou
final int[] buttonIds = { R.id.button01, R.id.button02, R.id.button03,
R.id.button04, R.id.button05, R.id.button06,
R.id.button07, R.id.button08, R.id.button09,
R.id.button10, R.id.button11, R.id.button12,
R.id.button13, R.id.button14, R.id.button15,
R.id.button16, R.id.button16, R.id.button17,
R.id.button18, R.id.button19, R.id.button20,
R.id.button21, R.id.button22, R.id.button23,
R.id.button24, R.id.button25 };
final int[] soundIds = { R.raw.sound01, R.raw.sound02, R.raw.sound03,
R.raw.sound04, R.raw.sound05, R.raw.sound06,
R.raw.sound07, R.raw.sound08, R.raw.sound09,
R.raw.sound10, R.raw.sound11, R.raw.sound12,
R.raw.sound13, R.raw.sound14, R.raw.sound15,
R.raw.sound16, R.raw.sound16, R.raw.sound17,
R.raw.sound18, R.raw.sound19, R.raw.sound20,
R.raw.sound21, R.raw.sound22, R.raw.sound23,
R.raw.sound24, R.raw.sound25 };
View.OnClickListener listener = new View.OnClickListener() {
public void onClick(View v) {
//find the index that matches the button's ID, and then reset
//the MediaPlayer instance, set the data source to the corresponding
//sound effect, prepare it, and start it playing.
for(int i = 0; i < buttonIds.length; i++) {
if(v.getId() == buttonIds[i]) {
selectedSoundId = soundIds[i];
AssetFileDescriptor afd = res.openRawResourceFd(soundIds[i]);
player.reset();
try {
player.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
player.prepare();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
player.start();
break;
}
}
}
};
//set the same listener for every button ID, no need
//to keep a reference to every button
for(int i = 0; i < buttonIds.length; i++) {
Button soundButton = (Button)findViewById(buttonIds[i]);
registerForContextMenu(soundButton);
soundButton.setOnClickListener(listener);
}
}
}
I have only one error:
newboard cannot be resolved, or is not a field Type: Java problem
A nice project download that could be used as a foundation would be optimal, if that exists!
Thanks in advance for any guidance!
Maytag87
The error means that it can't find your layout XML file.
Does the file /res/layout/newboard.xml exist in your Eclipse project? Perhaps the layout is called something else, like main.xml, in which case you should use R.layout.main in your Java code when you call setContentView().
in one activity I have 5 buttons. Each of these buttons make a different sound.
atm I'm doing on each buttonClicked method:
MediaPlayer mp = MediaPlayer.create(this, R.raw.click);
if(mp != null) mp.start();
MediaPlayer mp = MediaPlayer.create(this, R.raw.click2);
if(mp != null) mp.start();
etc..
is this the right way to do it, and I wonder since mp is local object, doesn't it die when the method dies, ergo no need to call mp.release() ?
note: my sounds are 0.5 sec or less and they seem to complete more often than not (haven't tested in many devices though). I'm targeting 2.1+
You need to declare your Mediaplayer reference globally need to assign mediaplayer object in the onCreate() then in button click call MediaPlayer.create(this/getApplicationContext(),R.Raw.yourfile); follow http://developer.android.com/reference/android/media/MediaPlayer.html#StateDiagram
mp.reset();
mp=MediaPlayer.create(getApplicationContext(),R.raw.hummingbird);
try {
mp.prepare();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mp.start();
I am very new to programming but through determination have found a way to make an application that allows a media url to be played through my app the issue is im trying to make it so that its open to more that 1 specific url for that specific song Im trying to make it so that a playlist that is already set on a site can be chosen through this player if anyone is up to helping me learn and or taking the time to work with me through email or messaging please let me know the code i have so far for this app is as follows
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
String url = "http://beatswith.us/uploads/Mac%20Miller%20-%20Paper%20Route%20feat.%20Kev%20Da%20Hustla.mp3"; // your URL here
MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
try {
mediaPlayer.setDataSource(url);
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
mediaPlayer.prepare();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} // might take long! (for buffering, etc)
mediaPlayer.start();
}
};
So if I'm reading your question right, it sounds like you currently have just one song your app will play but instead you want to be able to choose from a list of songs to play..
What you probably would want to do as a next step is create an array of songs and then use ListView to allow the user to pick which song they want to play. It looks like this may be your first time programming. I suggest you look up some tuturials showing how a list view works and then make an ArrayAdapter to bind to your ListView.. The ArrayAdapter has an array (think of an array as being a variable that has more than 1 thing in it, in your case Strings which represent URL's to songs..
Here is some code to get you started:
public class SongListActivity extends ListActivity {
static final String[] songList = new String[] {
"http://beatswith.us/uploads/Mac%20Miller%20-%20Paper%20Route%20feat.%20Kev%20Da%20Hustla.mp3",
"http://beatswith.us/another1.mp3",
"http://beatswith.us/another2.mp3"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
ArrayAdapter songAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, songList);
setListAdapter(songAdapter);
}
#Override
protected void onListItemClick(ListView lv, View v,int pos, long id) {
String url = (String) lv.getAdapter().getItem(pos);
playSong(url);
}
private void playSong(String url) {
MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
try {
mediaPlayer.setDataSource(url);
mediaPlayer.start();
} catch (Exception e) {
e.printStackTrace();
}
}
}
here is more documentation that should help:
http://developer.android.com/reference/android/app/ListActivity.html
You will need to update the array with valid URL's to songs.
-- Update --
I'm a bit confused still by the exact question.. I'm not sure what exactly you want to do.. If there is a playlist on a website (perhaps in xml format) you could download that xml file and then make a ListAdapter that you would use instead of an ArrayAdapter.. I mean really this gets much more complicated because in reality you probably want to show the name of the song so that means you need to parse the ID3 information from the mp3 -- which is relatively easy to do but it is definitely much more involved than what your current code does.. My example should give you a bit of an idea on how to play a list of songs and should get you a bit more programming experience before you move on to more complicated things.
i have created a music app.the app has 16 music btns.the app is running with no problem but as i press the btns many times the app forces down..
super.onCreate(icicle);
setContentView(R.layout.main);
int[] ids = {R.id.btn,R.id.btn2, R.id.btn3, R.id.btn4, R.id.btn5, R.id.btn6, R.id.btn7, R.id.btn8, R.id.btn9, R.id.btn10,
R.id.btn11, R.id.btn12, R.id.btn13, R.id.btn14, R.id.btn15, R.id.btn16 };
for (int i : ids) {
b = (Button) findViewById(i);
b.setOnClickListener(this);
}}
//outside of onCreate()
#Override
public void onClick(View v) {
switch(v.getId()) {
case R.id.btn:
if (mp != null && mp.isPlaying()) mp.stop();
mp = MediaPlayer.create(zoo.this, R.raw.gata);
mp.start();
break;
this is the code and i use case for every btn.When the app forces down, the logCat is finding a NullPointerException in the mp.start(); of the button that forces the app down..please help!
EDIT in from comment below:
case R.id.btn:
if (mp != null && mp.isPlaying()) mp.stop();
mp.reset();
try {
mp.setDataSource("zoo.this,R.raw.gata");
} catch (IllegalArgumentException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IllegalStateException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
mp.start();
break;
I think the point is that a MediaPlayer is a pretty heavy weight resource and you should not create too many of them. Also, as soon as you are done with it, call it's release() method. Anon's point's are both valid: you should try to reuse your media play instead of creating a new one and you should become very familiar with the MediaPlayer documentation. For instance from the MediaPlayer documentation:
Resource may include singleton
resources such as hardware
acceleration components and failure to
call release() may cause subsequent
instances of MediaPlayer objects to
fallback to software implementations
or fail altogether.
The hypothesis is that you are allocating lots of MediaPlayer objects and/or not releasing them fast enough. However, without more code it's impossible to be certain.