ListPreference

[size=medium][color=olive]preference_with_value.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:minHeight="?android:attr/listPreferredItemHeight"
android:gravity="center_vertical"
android:paddingRight="?android:attr/scrollbarSize">

<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="15dip"
android:layout_marginRight="6dip"
android:layout_marginTop="6dip"
android:layout_marginBottom="6dip"
android:layout_weight="1">

<LinearLayout
android:id="@+id/preference_first_line"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical">

<TextView android:id="@+android:id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="15dip"
android:layout_weight="1"
android:singleLine="true"
android:textAppearance="?android:attr/textAppearanceLarge"
android:ellipsize="marquee"
android:fadingEdge="horizontal" />

<TextView android:id="@+id/preference_value"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="10"
android:singleLine="true"
android:textAppearance="?android:attr/textAppearanceSmall"
android:gravity="right"
android:ellipsize="end" />

</LinearLayout>

<TextView android:id="@+android:id/summary"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/preference_first_line"
android:layout_alignLeft="@android:id/title"
android:textAppearance="?android:attr/textAppearanceSmall"
android:maxLines="2" />

</RelativeLayout>

</LinearLayout>

Code in Activity:

final ListPreference listPref = ...
listPref.setLayoutResource(R.layout.preference_with_value);
listPref.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
public boolean onPreferenceChange(Preference preference, Object newValue) {
TextView textView = (TextView) findViewById(R.id.preference_value);
int index = listPref.findIndexOfValue(newValue.toString());
if (index != -1) {
textView.setText(listPref.getEntries()[index]);
}
return true;
}
});

We can also write ListPreferenceWithValue and EditTextPreferenceWithValue classes to automate the above code:
package com.example;

import android.content.Context;
import android.preference.EditTextPreference;
import android.util.AttributeSet;
import android.view.View;
import android.widget.TextView;

public class EditTextPreferenceWithValue extends EditTextPreference {

private TextView mValueText;

public EditTextPreferenceWithValue(Context context, AttributeSet attrs) {
super(context, attrs);
setLayoutResource(R.layout.preference_with_value);
}

public EditTextPreferenceWithValue(Context context) {
super(context);
setLayoutResource(R.layout.preference_with_value);
}

@Override
protected void onBindView(View view) {
super.onBindView(view);
mValueText = (TextView) view.findViewById(R.id.preference_value);
if (mValueText != null) {
mValueText.setText(getText());
}
}

@Override
public void setText(String text) {
super.setText(text);
if (mValueText != null) {
mValueText.setText(getText());
}
}

}

preference_with_value.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:minHeight="?android:attr/listPreferredItemHeight"
android:gravity="center_vertical"
android:paddingRight="?android:attr/scrollbarSize">

<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="15dip"
android:layout_marginRight="6dip"
android:layout_marginTop="6dip"
android:layout_marginBottom="6dip"
android:layout_weight="1">

<LinearLayout
android:id="@+id/preference_first_line"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical">

<TextView android:id="@+android:id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="15dip"
android:layout_weight="1"
android:singleLine="true"
android:textAppearance="?android:attr/textAppearanceLarge"
android:ellipsize="marquee"
android:fadingEdge="horizontal" />

<TextView android:id="@+id/preference_value"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="10"
android:singleLine="true"
android:textAppearance="?android:attr/textAppearanceSmall"
android:gravity="right"
android:ellipsize="end" />

</LinearLayout>

<TextView android:id="@+android:id/summary"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/preference_first_line"
android:layout_alignLeft="@android:id/title"
android:textAppearance="?android:attr/textAppearanceSmall"
android:maxLines="2" />

</RelativeLayout>

</LinearLayout>

Code in Activity:

final ListPreference listPref = ...
listPref.setLayoutResource(R.layout.preference_with_value);
listPref.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
public boolean onPreferenceChange(Preference preference, Object newValue) {
TextView textView = (TextView) findViewById(R.id.preference_value);
int index = listPref.findIndexOfValue(newValue.toString());
if (index != -1) {
textView.setText(listPref.getEntries()[index]);
}
return true;
}
});

We can also write ListPreferenceWithValue and EditTextPreferenceWithValue classes to automate the above code:
package com.example;

import android.content.Context;
import android.preference.EditTextPreference;
import android.util.AttributeSet;
import android.view.View;
import android.widget.TextView;

public class EditTextPreferenceWithValue extends EditTextPreference {

private TextView mValueText;

public EditTextPreferenceWithValue(Context context, AttributeSet attrs) {
super(context, attrs);
setLayoutResource(R.layout.preference_with_value);
}

public EditTextPreferenceWithValue(Context context) {
super(context);
setLayoutResource(R.layout.preference_with_value);
}

@Override
protected void onBindView(View view) {
super.onBindView(view);
mValueText = (TextView) view.findViewById(R.id.preference_value);
if (mValueText != null) {
mValueText.setText(getText());
}
}

@Override
public void setText(String text) {
super.setText(text);
if (mValueText != null) {
mValueText.setText(getText());
}
}

}


Android Preference API already provide a unified UI style for preferences. However, for ListPreference, I feel some inconvenience about its default behaviors:

In the preference screen, the user can't see the current selected value of a ListPreference;
When the user selects an item in a list preference popup, the popup is dismissed immediately, without any UI feedback about which item has been selected.
I noticed that some applications change the behavior by displaying the current selected value in the place of the summary of the preference, which looks better to me. However, this causes there's no place to display the summary.

I think it might be better to display the current selected value at the right side of the ListPreference.

EditTextPreference has the similar problems. [/color][/size]