Help with SeekBarPreference screen

Hi guys,

I'm developing an app that via bluetooth controls few parameters of an external hardware.

To set this parameters, I've created a custom preference screen. When entering to the preference screen, 3 parameters are displayed, and to control these, I use a dialog preference that displays a seekbar, to select a value in a range from 0 to 100.

The problem is that, If I only use this custom preference screen with 1 parameter, it works fine, but when I enable the 3 parameters in the custom preference screen, the app crashes.

The code is the following:


Preferences.java

[HIGH]
public class Preferencias extends PreferenceActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.preferencias);

}

}[/HIGH]



SeekBarDialogPreference.java

[HIGH]public class SeekBarDialogPreference extends DialogPreference
{
private static final int DEFAULT_MIN_PROGRESS = 0;
private static final int DEFAULT_MAX_PROGRESS = 100;
private static final int DEFAULT_PROGRESS = 0;

private int mMinProgress;
private int mMaxProgress;
private int mProgress;
private CharSequence mProgressTextSuffix;
private TextView mProgressText;
private SeekBar mSeekBar;

public SeekBarDialogPreference(Context context)
{
this(context, null);
}

public SeekBarDialogPreference(Context context, AttributeSet attrs)
{
super(context, attrs);

// get attributes specified in XML
TypedArray a = context.getTheme().obtainStyledAttributes(attrs, R.styleable.SeekBarDialogPreference, 0, 0);
try
{
setMinProgress(a.getInteger(R.styleable.SeekBarDialogPreference_min, DEFAULT_MIN_PROGRESS));
setMaxProgress(a.getInteger(R.styleable.SeekBarDialogPreference_android_max, DEFAULT_MAX_PROGRESS));
setProgressTextSuffix(a.getString(R.styleable.SeekBarDialogPreference_progressTextSuffix));
}
finally
{
a.recycle();
}

// set layout
setDialogLayoutResource(R.layout.preference_seek_bar_dialog);
setPositiveButtonText(android.R.string.ok);
setNegativeButtonText(android.R.string.cancel);
setDialogIcon(null);
}

@Override
protected void onSetInitialValue(boolean restore, Object defaultValue)
{
setProgress(restore ? getPersistedInt(DEFAULT_PROGRESS) : (Integer) defaultValue);
}

@Override
protected Object onGetDefaultValue(TypedArray a, int index)
{
return a.getInt(index, DEFAULT_PROGRESS);
}

@Override
protected void onBindDialogView(View view)
{
super.onBindDialogView(view);

TextView dialogMessageText = (TextView) view.findViewById(R.id.text_dialog_message);
dialogMessageText.setText(getDialogMessage());

mProgressText = (TextView) view.findViewById(R.id.text_progress);

mSeekBar = (SeekBar) view.findViewById(R.id.seek_bar);
mSeekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener()
{
@Override
public void onStopTrackingTouch(SeekBar seekBar)
{
}

@Override
public void onStartTrackingTouch(SeekBar seekBar)
{
}

@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser)
{
// update text that displays the current SeekBar progress value
// note: this does not persist the progress value. that is only ever done in setProgress()
String progressStr = String.valueOf(progress + mMinProgress);
mProgressText.setText(mProgressTextSuffix == null ? progressStr : progressStr.concat(mProgressTextSuffix.toString()));
}
});
mSeekBar.setMax(mMaxProgress - mMinProgress);
mSeekBar.setProgress(mProgress - mMinProgress);
}

public int getMinProgress()
{
return mMinProgress;
}

public void setMinProgress(int minProgress)
{
mMinProgress = minProgress;
setProgress(Math.max(mProgress, mMinProgress));
}

public int getMaxProgress()
{
return mMaxProgress;
}

public void setMaxProgress(int maxProgress)
{
mMaxProgress = maxProgress;
setProgress(Math.min(mProgress, mMaxProgress));
}

public int getProgress()
{
return mProgress;
}

public void setProgress(int progress)
{
progress = Math.max(Math.min(progress, mMaxProgress), mMinProgress);

if (progress != mProgress)
{
mProgress = progress;
persistInt(progress);
notifyChanged();
}
}

public CharSequence getProgressTextSuffix()
{
return mProgressTextSuffix;
}

public void setProgressTextSuffix(CharSequence progressTextSuffix)
{
mProgressTextSuffix = progressTextSuffix;
}

@Override
protected void onDialogClosed(boolean positiveResult)
{
super.onDialogClosed(positiveResult);

// when the user selects "OK", persist the new value
if (positiveResult)
{
int seekBarProgress = mSeekBar.getProgress() + mMinProgress;
if (callChangeListener(seekBarProgress))
{
setProgress(seekBarProgress);
}
}
}

@Override
protected Parcelable onSaveInstanceState()
{
// save the instance state so that it will survive screen orientation changes and other events that may temporarily destroy it
final Parcelable superState = super.onSaveInstanceState();

// set the state's value with the class member that holds current setting value
final SavedState myState = new SavedState(superState);
myState.minProgress = getMinProgress();
myState.maxProgress = getMaxProgress();
myState.progress = getProgress();

return myState;
}

@Override
protected void onRestoreInstanceState(Parcelable state)
{
// check whether we saved the state in onSaveInstanceState()
if (state == null || !state.getClass().equals(SavedState.class))
{
// didn't save the state, so call superclass
super.onRestoreInstanceState(state);
return;
}

// restore the state
SavedState myState = (SavedState) state;
setMinProgress(myState.minProgress);
setMaxProgress(myState.maxProgress);
setProgress(myState.progress);

super.onRestoreInstanceState(myState.getSuperState());
}

private static class SavedState extends BaseSavedState
{
int minProgress;
int maxProgress;
int progress;

public SavedState(Parcelable superState)
{
super(superState);
}

public SavedState(Parcel source)
{
super(source);

minProgress = source.readInt();
maxProgress = source.readInt();
progress = source.readInt();
}

@Override
public void writeToParcel(Parcel dest, int flags)
{
super.writeToParcel(dest, flags);

dest.writeInt(minProgress);
dest.writeInt(maxProgress);
dest.writeInt(progress);
}

@SuppressWarnings("unused")
public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>()
{
@Override
public SavedState createFromParcel(Parcel in)
{
return new SavedState(in);
}

@Override
public SavedState[] newArray(int size)
{
return new SavedState[size];
}
};
}
}[/HIGH]


preference_seek_bar_dialog.xml

[HIGH]<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
androidrientation="vertical" >

<TextView
android:id="@+id/text_dialog_message"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="6dip"
androidaddingLeft="12dip"
androidaddingRight="12dip" >
</TextView>

<TextView
android:id="@+id/text_progress"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="6dip"
android:gravity="center_horizontal" >
</TextView>

<SeekBar
android:id="@+id/seek_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="6dip"
android:layout_marginTop="6dip" />

</LinearLayout>[/HIGH]



Preferences.xml

[HIGH]<PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android"
android:key="preferencias_principal"
xmlns:custom="http://schemas.android.com/apk/res-auto" >

<.....SeekBarDialogPreference
android:key="fast"
android:title="@string/listtittle1"
android:summary="@string/summary1"
android:defaultValue="40"
android:dialogMessage="Please select a value:"
android:max="100"
customrogressTextSuffix="%"
custom:min="0" />

<.....SeekBarDialogPreference
android:key="climb"
android:title="@string/listtittle2"
android:summary="@string/summary2"
android:defaultValue="80"
android:dialogMessage="Please select a value:"
android:max="100"
customrogressTextSuffix="%"
custom:min="0" />

<....SeekBarDialogPreference
android:key="platform"
android:title="@string/listtittle3"
android:summary="@string/summary3"
android:defaultValue="60"
android:dialogMessage="Please select a value:"
android:max="100"
customrogressTextSuffix="%"
custom:min="0" />

</PreferenceScreen>[/HIGH]