如何使用 android:layout 属性实例化自定义首选项的布局

Question

我可以通过 android:layout 属性设置适当的布局。 示例

<Preference
  android:key="friction" 
  android:title="@string/friction" 
  android:layout="@layout/friction_fragment" 
  android:shouldDisableView="true" 
  android:defaultValue="30" 
  android:enabled="true"
  android:selectable="true" 
  android:summary="Bite friction">
</Preference>

对于布局的

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
    <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:text="@string/friction" android:textAppearance="?android:attr/textAppearanceLarge" android:layout_height="wrap_content" android:layout_gravity="center_horizontal"></TextView>
    <SeekBar android:layout_height="wrap_content" android:layout_width="fill_parent" android:id="@+id/sbFriction"></SeekBar>
    <TextView android:text="@string/friction_little" android:id="@+id/txtSummary" android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView>
    <Button android:text="Button" android:id="@+id/btnFriction" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button>

</LinearLayout>

，我可以在 PreferenceActivity 的 OnCreate 中获取视图，

    Preference fric = (Preference)this.findPreference("friction");
    View v = fric.getView(null, null);
    SeekBar sbFriction = (SeekBar)v.findViewById(R.id.sbFriction);
    sbFriction.setOnSeekBarChangeListener(this);
    Button btnFric = (Button) v.findViewById(R.id.btnFriction);
    btnFric.setOnClickListener(m_onClick);

但我设置的这些事件侦听器不会被触发。 例如，我如何捕获这些事件 - 单击按钮。 编辑。 不，它没有引发任何异常。 这是更详细的代码

public class SettingsActivity extends PreferenceActivity implements OnPreferenceChangeListener, OnSeekBarChangeListener
{

    private TextView m_txtSummary;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);

        ListPreference difficulty = (ListPreference)this.findPreference("difficulty");
        difficulty.setSummary(difficulty.getEntry());
        difficulty.setOnPreferenceChangeListener(this);

        Preference fric = (Preference)this.findPreference("friction");
        View v = fric.getView(null, null);
        SeekBar sbFriction = (SeekBar)v.findViewById(R.id.sbFriction);
        sbFriction.setOnSeekBarChangeListener(this);
        Button btnFric = (Button) v.findViewById(R.id.btnFriction);
        btnFric.setOnClickListener(m_onClick);

        m_txtSummary = (TextView)v.findViewById(R.id.txtSummary);

        fric.setSummary(fric.toString());
        fric.setOnPreferenceChangeListener(this);

        CheckBoxPreference music = (CheckBoxPreference)this.findPreference("music");
        music.setOnPreferenceChangeListener(this);
    }

    private OnClickListener m_onClick = new OnClickListener(){

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            v.getId();
        }

    };

    @Override
    public boolean onPreferenceChange(Preference preference, Object newValue) {
        if(newValue instanceof Boolean)
            return true;

        preference.setSummary(newValue.toString());
        return true;
    }

    @Override
    public void onProgressChanged(SeekBar v, int nProgress, boolean arg2) {
        // TODO Auto-generated method stub
        m_txtSummary.append(" " + nProgress);
        m_txtSummary.invalidate();
    }

    @Override
    public void onStartTrackingTouch(SeekBar arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStopTrackingTouch(SeekBar arg0) {
        // TODO Auto-generated method stub
        //notifyChanged();
    }
}

Answer 1

我不确定您是否能够按照上面描述的方式将自定义布局与 PreferenceActivity 结合使用。

我相信您应该：

通过 addPreferencesFromResource() 使用 PreferenceScreen 并实现 CheckBoxPreference、DialogPreference 和SharedPreferences 项的 MultiSelectListPreference。 （示例）

或

创建自定义Activity （不是 PreferenceActivity）使用自定义布局（使用 setContentView()），并使用以下命令手动挂接到 SharedPreferences PreferenceManager.getDefaultSharedPreferences() 使用 SharedPreferences.Editor 在事件监听器（View.onClickListener() 等）中编辑它们。

希望这是有道理的。

Answer 2

实际上我找到了另一个解决方案。您仍然可以使用首选项：

只需添加一个调用自定义布局的片段并添加它的类。
但是，您会在清单中收到警告：（您可以忽略或修复）

[res] (AndroidManifest.xml)

               android:name=".SettingsActivity_CUSTOMLAYOUT1"

“YOURPACKAGE.SettingsActivity_CUSTOMLAYOUT1 不是公开的”

它仅从您的 SettingsActivity 中调用，因此您可以忽略它

，或者

如果您愿意的话要从外部调用此 Activity，只需为其创建一个自己的类并将其命名为 SettingsActivity_CUSTOMLAYOUT1.java。

代码：

[java] (SettingsActivity.java)

public class SettingsActivity extends AppCompatPreferenceActivity {

    private static Preference.OnPreferenceChangeListener sBindPreferenceSummaryToValueListener = new Preference.OnPreferenceChangeListener() {
        @Override
        public boolean onPreferenceChange(Preference preference, Object value) {
            String stringValue = value.toString();

            if (preference instanceof ListPreference) {
                ListPreference listPreference = (ListPreference) preference;
                int index = listPreference.findIndexOfValue(stringValue);
                preference.setSummary(
                        index >= 0
                                ? listPreference.getEntries()[index]
                                : null);

            } else if (preference instanceof RingtonePreference) {
                if (TextUtils.isEmpty(stringValue)) {
                    preference.setSummary(R.string.pref_ringtone_silent);

                } else {
                    Ringtone ringtone = RingtoneManager.getRingtone(
                            preference.getContext(), Uri.parse(stringValue));

                    if (ringtone == null) {                          
                        preference.setSummary(null);
                    } else {
                        String name = ringtone.getTitle(preference.getContext());
                        preference.setSummary(name);
                    }
                }

            } else {
                preference.setSummary(stringValue);
            }
            return true;
        }
    };

    private static boolean isXLargeTablet(Context context) {
        return (context.getResources().getConfiguration().screenLayout
                & Configuration.SCREENLAYOUT_SIZE_MASK) >= Configuration.SCREENLAYOUT_SIZE_XLARGE;
    }

    private static void bindPreferenceSummaryToValue(Preference preference) {
        preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener);
        sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
                PreferenceManager
                        .getDefaultSharedPreferences(preference.getContext())
                        .getString(preference.getKey(), ""));
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setupActionBar();
    }


    private void setupActionBar() {
        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
    }

    @Override
    public boolean onIsMultiPane() {
        return isXLargeTablet(this);
    }

    @Override
    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    public void onBuildHeaders(List<Header> target) {
        loadHeadersFromResource(R.xml.pref_headers, target);
    }

    protected boolean isValidFragment(String fragmentName) {
        return PreferenceFragment.class.getName().equals(fragmentName)
                || YOURFRAGMENT1.class.getName().equals(fragmentName)
                || YOURFRAGMENT2.class.getName().equals(fragmentName)
                || CUSTOMLAYOUT1.class.getName().equals(fragmentName)
                //... Add Fragments
    }

    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    public static class YOURFRAGMENT1 extends PreferenceFragment {
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            addPreferencesFromResource(R.xml.YOURFRAGMENTXML1);
            setHasOptionsMenu(true);    
        }

        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            int id = item.getItemId();
            if (id == android.R.id.home) {
                startActivity(new Intent(getActivity(), SettingsActivity.class));
                return true;
            }
            return super.onOptionsItemSelected(item);
        }
    }

    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    public static class YOURFRAGMENT2 extends PreferenceFragment {
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            addPreferencesFromResource(R.xml.pref_private_data);
            setHasOptionsMenu(true);    
        }

        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            int id = item.getItemId();
            if (id == android.R.id.home) {
                startActivity(new Intent(getActivity(), SettingsActivity.class));
                return true;
            }
            return super.onOptionsItemSelected(item);
        }
    }

    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    public static class FRAGMENTFORCUSTOMLAYOUT1 extends PreferenceFragment {
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            startActivity(new Intent(getActivity(), SettingsActivity.class));       
            startActivity(new Intent(getActivity(), CUSTOMLAYOUT1.class));
            setHasOptionsMenu(true);

        }

        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            int id = item.getItemId();
            if (id == android.R.id.home) {
                startActivity(new Intent(getActivity(), SettingsActivity.class));
                return true;
            }
            return super.onOptionsItemSelected(item);
        }
    }   

}

class SettingsActivity_CUSTOMLAYOUT1 extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.CUSTOMLAYOUT1);

        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                finish();
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
}

[xml] (pref_headers.xml)

<preference-headers xmlns:android="http://schemas.android.com/apk/res/android">

        <header
        android:fragment="YOURPACKAGE.SettingsActivity$YOURFRAGMENT1"
        android:icon="@drawable/YOURICON"
        android:title="@string/TITLE"       
        android:summary="@string/SUBTITLE"/>

        <header
        android:fragment="YOURPACKAGE.SettingsActivity$YOURFRAGMENT2"
        android:icon="@drawable/YOURICON"
        android:title="@string/TITLE"       
        android:summary="@string/SUBTITLE"/>

        <header
        android:fragment="YOURPACKAGE.SettingsActivity$CUSTOMLAYOUT1"
        android:icon="@drawable/YOURICON"
        android:title="@string/TITLE"       
        android:summary="@string/SUBTITLE"/>


</preference-headers>

[layout] (CUSTOMLAYOUT1.xml)

<?xml version="1.0" encoding="utf-8"?>
<...your custom layout>

不要忘记在 Manifest 中添加。

[资源] (AndroidManifest.xml)

<?xml version="1.0" encoding="utf-8"?>
<manifest>
    <application   

        //Add activity
        <activity
            android:name=".SettingsActivity_CUSTOMLAYOUT1"
            android:parentActivityName=".SettingsActivity">
        </activity>


    </application>

</manifest>