Custom volume control preference

I made a custom preference by referring to the online code and did not use the Android: Layout attribute of preference, because it is always difficult to align with the control of other preference on different versions of the system, therefore, you can set only Android: widget_layout.

Create your own widget_layout file "preference_widget_seekbar.xml ":

 

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:gravity="center_vertical"    android:minHeight="?android:attr/listPreferredItemHeight"    android:paddingRight="?android:attr/scrollbarSize" >    <SeekBar        android:id="@+id/seekBar1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:max="60"        android:minWidth="240dip"        android:paddingRight="5dp"        android:progress="20"        android:textIsSelectable="true" >    </SeekBar>        <TextView        android:id="@+id/seekBarPrefValue"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@id/seekBar1"        android:layout_centerHorizontal="true"        android:textIsSelectable="true" ></TextView>    <TextView        android:id="@+id/seekBarPrefUnitsLeft"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@id/seekBar1"        android:layout_toLeftOf="@id/seekBarPrefValue"        android:textIsSelectable="true" ></TextView>    <TextView        android:id="@+id/seekBarPrefUnitsRight"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textIsSelectable="true"        android:layout_below="@id/seekBar1"         android:layout_toRightOf="@id/seekBarPrefValue" ></TextView></RelativeLayout>

 

 

Creates the com. sample. Preference. seekbarpreference class to initialize the interface and synchronize the preference data represented by the volume slider.

 

package com.sample.preference;import com.sample.R;

import android.content.Context;import android.content.res.TypedArray;import android.preference.Preference;import android.util.AttributeSet;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.view.ViewParent;import android.widget.RelativeLayout;import android.widget.SeekBar;import android.widget.SeekBar.OnSeekBarChangeListener;import android.widget.TextView;public class SeekBarPreference extends Preference implements OnSeekBarChangeListener{        private final String TAG = "SeekBarPreference";        //private static final String ANDROIDNS="http://schemas.android.com/apk/res/android";    private static final String SEEKBAR_PREFS="SeekBarPreference";    private static final int DEFAULT_VALUE = 50;        Context mContext;private int mMaxValue      = 100;private int mMinValue      = 0;private int mInterval      = 1;private int mCurrentValue  = 50;private String mUnitsLeft  = "";private String mUnitsRight = "";private SeekBar mSeekBar;    private TextView mCurrentValueText;    public SeekBarPreference(Context context, AttributeSet attrs) {        super(context, attrs);        initPreference(context, attrs);    }    public SeekBarPreference(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        initPreference(context, attrs);    }    private void initPreference(Context context, AttributeSet attrs) {    Log.v(TAG,"initPreference");    mContext = context;        updateValuesFromXml(attrs);        this.setWidgetLayoutResource(R.layout.preference_widget_seekbar);    }        private void updateValuesFromXml(AttributeSet attrs) {        mMaxValue = attrs.getAttributeIntValue(SEEKBAR_PREFS, "max", 100);        mMinValue = attrs.getAttributeIntValue(SEEKBAR_PREFS, "min", 0);               mUnitsLeft = getAttributeStringValue(attrs, SEEKBAR_PREFS, "unitsLeft", "");        String value = getAttributeStringValue(attrs, SEEKBAR_PREFS, "value", "");        mUnitsRight = getAttributeStringValue(attrs, SEEKBAR_PREFS, "unitsRight", "");                try {        mInterval = attrs.getAttributeIntValue(SEEKBAR_PREFS, "interval", 1);            if( mInterval <= 0 )            {            mInterval = 1;            }        }        catch(Exception e) {            Log.e(TAG, "Invalid interval value", e);        }            }        private String getAttributeStringValue(AttributeSet attrs, String namespace, String name, String defaultValue) {        String value = attrs.getAttributeValue(namespace, name);        if(value == null)            value = defaultValue;                return value;    }        @Override    protected View onCreateView(ViewGroup parent){    Log.v(TAG, "onCreateView()");        return super.onCreateView(parent);    }        @Override    public void onBindView(View view) {        super.onBindView(view);                View layout = view;        Log.v(TAG, "onBindView()");        mSeekBar = (SeekBar)view.findViewById(R.id.seekBar1);        mCurrentValueText = (TextView)view.findViewById(R.id.seekBarPrefValue);        if( null != mCurrentValueText ){        mCurrentValueText.setText(String.valueOf(mCurrentValue));        mCurrentValueText.setMinimumWidth(30);        }        if( null != mSeekBar )        {        mSeekBar.setMax(mMaxValue - mMinValue);        mSeekBar.setProgress(mCurrentValue - mMinValue);        mSeekBar.setOnSeekBarChangeListener(this);        }        TextView unitsRight = (TextView)view.findViewById(R.id.seekBarPrefUnitsRight);        if( null != unitsRight ){        unitsRight.setText(mUnitsRight);        }                TextView unitsLeft = (TextView)view.findViewById(R.id.seekBarPrefUnitsLeft);        if( null != unitsLeft ){        unitsLeft.setText(mUnitsLeft);          }    }        @Override    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {        int newValue = progress + mMinValue;                if(newValue > mMaxValue)            newValue = mMaxValue;        else if(newValue < mMinValue)            newValue = mMinValue;        else if(mInterval != 1 && newValue % mInterval != 0)            newValue = Math.round(((float)newValue)/mInterval)*mInterval;                  // change rejected, revert to the previous value        if(!callChangeListener(newValue)){            seekBar.setProgress(mCurrentValue - mMinValue);             return;         }        // change accepted, store it        mCurrentValue = newValue;        if( null != mCurrentValueText ){        mCurrentValueText.setText(String.valueOf(newValue));        }        persistInt(newValue);    }    @Override    public void onStartTrackingTouch(SeekBar seekBar) {}    @Override    public void onStopTrackingTouch(SeekBar seekBar) {        notifyChanged();    }    @Override     protected Object onGetDefaultValue(TypedArray ta, int index){                int defaultValue = ta.getInt(index, DEFAULT_VALUE);        return defaultValue;            }    @Override    protected void onSetInitialValue(boolean restoreValue, Object defaultValue) {        if(restoreValue) {            mCurrentValue = getPersistedInt(mCurrentValue);        }        else {            int temp = 0;            try {                temp = (Integer)defaultValue;            }            catch(Exception ex) {                Log.e(TAG, "Invalid default value: " + defaultValue.toString());            }                        persistInt(temp);            mCurrentValue = temp;        }            }    } 

 

 

Finally, add the corresponding item to preference XML.

 

<? XML version = "1.0" encoding = "UTF-8"?> <Preferencescreen xmlns: Android = "http://schemas.android.com/apk/res/android" Android: Title = "audiosetting"> <! --... Other preference items --> <com. sample. Preference. seekbarpreference Android: Key = "key_nes_volume_option" Android: Title = "volumesetting" Android: Summary = "volumesettingsummary"/>

<! --... Other preference items -->

</PreferenceScreen>