Android 代码实现preference组件

刺骨的言语ヽ痛彻心扉 2022-08-24 05:15 245阅读 0赞

Preference主要实现一些配置数据，一些我们上次点击选择的内容，我们希望在下次应用调起的时候依然有效，无须用户再一次进行配置或选择。Android提供preference这个键值对的方式来处理这种情况，自动保存这些数据，并立时生效，同时Android提供一种类似的layout的方式来进行Preference的布局。

Preference组件有ListPreference,EditTextPreference,CheckBoxPreference和SwitchPreference,相对于View中的ListView,EditText,CheckBox,Switch和RingtonePreference .

1.介绍Preference组件的相关属性

**         **android:key ：          每个Preference控件独一无二的”ID”,唯一表示此Preference。

android:defaultValue ： 默认值。 例如，CheckPreference的默认值可为”true”，默认为选中状态；

EditTextPreference的默认值可为”110”。

android:enabled ：      表示该Preference是否可用状态。

android:title ：        每个Preference在PreferenceScreen布局上显示的标题——大标题

android:summary ：      每个Preference在PreferenceScreen布局上显示的标题——小标题(可以没有)

android:persistent：    表示Preference元素所对应的值是否写入sharedPreferen文件中，如果是true，则表示写

入；否则，则表示不写入该Preference元素的值。

android:dependency：    表示一个Preference(用A表示)的可用状态依赖另外一个Preference(用B表示)。B可用，

则A可用；B不可用，则A不可用。

android:disableDependentsState：  与android:dependency相反。B可用，则A不可用；B不可用，则A可用。

特性：ListPreference

android:dialogTitle：弹出控件对话框时显示的标题

android:entries：类型为array，控件欲显示的文本

android:entryValues：类型为array，与文本相对应的key-value键值对，value保存至sharedPreference文件

RingtonePreference

**             **android:ringtoneType：响铃的铃声类型，主要有：ringtone(音乐)、notification(通知)、alarm(闹铃)

、all(所有可用声 音类型)。

android:showDefault ：默认铃声，可以使用系统(布尔值---true,false)的或者自定义的铃声

android:showSilent  ：指定铃声是否为静音。指定铃声包括系统默认铃声或者自定义的铃声

2.实例实现上述所讲控件

1> 代码目录结构

![Center][]

2>效果图

![Center 1][]![Center 2][]

3>xml相关文件

a.xml-> setting\_preference.xml

Preference的xml文件不是放在res->layout下，而是需要新建一个xml文件夹，将setting\_preference.xml放置在该xml文件夹下：

<?xml version="1.0" encoding="utf-8"?>
    <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >
    
        <PreferenceCategory android:title="第一项" >
            <ListPreference
                android:defaultValue="Green"
                android:dialogTitle="请选您需要的颜色"
                android:entries="@array/my_color_array"
                android:entryValues="@array/my_color_array"
                android:key="list_key"
                android:summary="Green"
                android:title="颜色设置" >
            </ListPreference>
        </PreferenceCategory>
        <PreferenceCategory android:title="第二项" >
            <EditTextPreference
                android:defaultValue="this is editTextPreference"
                android:dialogIcon="@drawable/ic_launcher"
                android:dialogTitle="请输入"
                android:key="edit_text_key"
                android:summary="this is editTextPreference"
                android:title="文本输入框" >
            </EditTextPreference>
        </PreferenceCategory>
        <PreferenceCategory android:title="第三项" >
            <CheckBoxPreference
                android:key="check_box_key"
                android:defaultValue="true"
                android:title="CheckBox" >
            </CheckBoxPreference>
    
            <SwitchPreference
                android:key="switch_key"
                android:defaultValue="true"
                android:title="Switch" >
            </SwitchPreference>
    
            <Preference
                android:key="preference_key"
                android:title="关于" >
            </Preference>
        </PreferenceCategory>
        <PreferenceCategory android:title="第四项" >
            <RingtonePreference
                android:key="ring_tone_key"
                android:title="Ringtone"
                android:summary="默认铃声"
                android:ringtoneType="alarm"
                ></RingtonePreference>
        </PreferenceCategory>
    </PreferenceScreen>

b.layout->activity\_ main.xml

c.layout->activity\_about.xml

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical" >
        
    	<TextView
    	    android:layout_width="fill_parent"
    	    android:layout_height="fill_parent"
    	    android:text="welcome to my preference"
    	    android:textSize="20sp"
    	    android:gravity="center"
    	    ></TextView>
    </LinearLayout>

d.value->array.xml

<?xml version="1.0" encoding="utf-8"?>
    <resources>
        <string-array name="my_color_array">
            <item>Red</item>
            <item>Green</item>
            <item>Bule</item>
        </string-array>
    </resources>

4>. java代码实现

a. 常量ConstantUtil.java

package com.example.settingdemo;
    
    public class ConstantUtil {
    	public static final String LIST_KEY = "list_key";
    	public static final String EDIT_TEXT_KEY = "edit_text_key";
    	public static final String CHECK_BOX_KEY = "check_box_key";
    	public static final String SWITCH_KEY = "switch_key";
    	public static final String RING_TONE_KEY = "ring_tone_key";
    	public static final String PREFERENCE_KEY = "preference_key";
    	public static final String MY_PREFERENCE_KEY = "my_preference_key";
    }

b. 主界面MainActivity.java

package com.example.settingdemo;
    
    import android.app.Activity;
    import android.content.Intent;
    import android.content.SharedPreferences;
    import android.os.Bundle;
    import android.preference.PreferenceManager;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.TextView;
    
    public class MainActivity extends Activity implements OnClickListener {
    
    	private Button settingBtn, showSettingInfoBtn;
    	private TextView showInfoTv;
    
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_main);
    
    		settingBtn = (Button) this.findViewById(R.id.setting_btn);
    		showSettingInfoBtn = (Button) this
    				.findViewById(R.id.show_setting_info_btn);
    		showInfoTv = (TextView) this.findViewById(R.id.show_info_tv);
    
    		settingBtn.setOnClickListener(this);
    		showSettingInfoBtn.setOnClickListener(this);
    	}
    
    	@Override
    	public void onResume() {
    		super.onResume();
    		showSettingInfo();
    	}
    
    	/**
    	 * 显示设置信息
    	 */
    	private void showSettingInfo() {
    		SharedPreferences share = PreferenceManager
    				.getDefaultSharedPreferences(this);
    		StringBuffer info = new StringBuffer();
    		String listInfo = share.getString(ConstantUtil.LIST_KEY, "Green");
    		String editTextInfo = share.getString(ConstantUtil.EDIT_TEXT_KEY,
    				"this is editTextPreference");
    		boolean checkBoxInfo = share.getBoolean(ConstantUtil.CHECK_BOX_KEY,
    				true);
    		boolean switchInfo = share.getBoolean(ConstantUtil.SWITCH_KEY, true);
    		String ringtoneInfo = share.getString(ConstantUtil.RING_TONE_KEY,
    				"默认铃声");
    
    		info.append("ListInfo:").append(listInfo).append("\n")
    				.append("editTextInfo:").append(editTextInfo).append("\n")
    				.append("checkBoxInfo:").append(checkBoxInfo).append("\n")
    				.append("switchInfo:").append(switchInfo).append("\n")
    				.append("ringtoneInfo:").append(ringtoneInfo).append("\n");
    
    		showInfoTv.setText(info.toString());
    	}
    
    	@Override
    	public boolean onCreateOptionsMenu(Menu menu) {
    
    		// Inflate the menu; this adds items to the action bar if it is present.
    		getMenuInflater().inflate(R.menu.main, menu);
    		return true;
    	}
    
    	@Override
    	public boolean onOptionsItemSelected(MenuItem item) {
    		// Handle action bar item clicks here. The action bar will
    		// automatically handle clicks on the Home/Up button, so long
    		// as you specify a parent activity in AndroidManifest.xml.
    		int id = item.getItemId();
    		if (id == R.id.action_settings) {
    			return true;
    		}
    		return super.onOptionsItemSelected(item);
    	}
    
    	@Override
    	public void onClick(View v) {
    		// TODO Auto-generated method stub
    		switch (v.getId()) {
    		case R.id.setting_btn:
    			Intent intent = new Intent(MainActivity.this, SettingActivity.class);
    			startActivity(intent);
    			break;
    		case R.id.show_setting_info_btn:
    			showSettingInfo();
    			break;
    		}
    	}
    
    }

c. 设置界面SettingActivity.java

package com.example.settingdemo;
    
    import android.content.Intent;
    import android.content.SharedPreferences;
    import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
    import android.os.Bundle;
    import android.preference.CheckBoxPreference;
    import android.preference.EditTextPreference;
    import android.preference.ListPreference;
    import android.preference.Preference;
    import android.preference.Preference.OnPreferenceClickListener;
    import android.preference.PreferenceActivity;
    import android.preference.RingtonePreference;
    import android.preference.SwitchPreference;
    import android.widget.Toast;
    
    public class SettingActivity extends PreferenceActivity implements OnSharedPreferenceChangeListener,OnPreferenceClickListener{
    	
    	private ListPreference mListPreference;
    	private EditTextPreference mEditTextPreference;
    	private CheckBoxPreference mCheckBoxPreference;
    	private SwitchPreference mSwitchPreference;
    	private Preference mPreference;
    	private RingtonePreference mRingtonePreference;
    	@SuppressWarnings("deprecation")
    	@Override
    	public void onCreate(Bundle savedInstanceState){
    		super.onCreate(savedInstanceState);
    		this.addPreferencesFromResource(R.xml.setting_preference);
    		
    		initPreference();
    	}
    
    	@SuppressWarnings("deprecation")
    	private void initPreference(){
    		mListPreference = (ListPreference) this.findPreference(ConstantUtil.LIST_KEY);
    		mEditTextPreference = (EditTextPreference) this.findPreference(ConstantUtil.EDIT_TEXT_KEY);
    		mCheckBoxPreference = (CheckBoxPreference) this.findPreference(ConstantUtil.CHECK_BOX_KEY);
    		mSwitchPreference = (SwitchPreference) this.findPreference(ConstantUtil.SWITCH_KEY);
    		mPreference = (Preference) this.findPreference(ConstantUtil.PREFERENCE_KEY);
    		mRingtonePreference = (RingtonePreference) this.findPreference(ConstantUtil.RING_TONE_KEY);
    		
    		mPreference.setOnPreferenceClickListener(this);
    	}
    	
    	@SuppressWarnings("deprecation")
    	@Override
    	public void onResume(){
    		super.onResume();
    		SharedPreferences share = this.getPreferenceScreen().getSharedPreferences();
    		
    		setDefaultSummary(share);
    		
    		share.registerOnSharedPreferenceChangeListener(this);
    	}
    	
    	@SuppressWarnings("deprecation")
    	@Override
    	public void onPause(){
    		super.onPause();
    		
    		this.getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
    	}
    	
    	/**
    	 * 设置组件小标题
    	 * @param share
    	 */
    	private void setDefaultSummary(SharedPreferences share){
    		mListPreference.setSummary(share.getString(ConstantUtil.LIST_KEY, "Green"));
    		mEditTextPreference.setSummary(share.getString(ConstantUtil.EDIT_TEXT_KEY, "this is editTextPreference"));
    		mRingtonePreference.setSummary(share.getString(ConstantUtil.RING_TONE_KEY, "默认铃声"));
    	}
    	
    	@Override
    	public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
    			String key) {
    		// TODO Auto-generated method stub
    		if(ConstantUtil.LIST_KEY.equals(key)){
    			mListPreference.setSummary(mListPreference.getEntry());
    		}else if(ConstantUtil.EDIT_TEXT_KEY.equals(key)){
    			mEditTextPreference.setSummary(sharedPreferences.getString(key, "this is editTextPreference"));
    		}else if(ConstantUtil.RING_TONE_KEY.equals(key)){
    			mRingtonePreference.setSummary(sharedPreferences.getString(key, "默认铃声"));
    		}
    	}
    
    	@Override
    	public boolean onPreferenceClick(Preference preference) {
    		// TODO Auto-generated method stub
    		if(ConstantUtil.PREFERENCE_KEY.equals(preference.getKey())){
    			Intent intent = new Intent(SettingActivity.this,AboutActivity.class);
    			startActivity(intent);
    		}else if(ConstantUtil.MY_PREFERENCE_KEY.equals(preference.getKey())){
    			Toast.makeText(this, "点击MyPreference", Toast.LENGTH_SHORT).show();
    		}
    		return false;
    	}
    }

d.跳转界面AboutActivity.java

package com.example.settingdemo;
    
    import android.app.Activity;
    import android.os.Bundle;
    
    public class AboutActivity extends Activity {
    	@Override
    	public void onCreate(Bundle savedInstanceState){
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.activity_about);
    	}
    }

5>. 清单AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.example.settingdemo"
        android:versionCode="1"
        android:versionName="1.0" >
    
        <uses-sdk
            android:minSdkVersion="8"
            android:targetSdkVersion="19" />
    
        <application
            android:allowBackup="true"
            android:icon="@drawable/ic_launcher"
            android:label="@string/app_name"
            android:theme="@style/AppTheme" >
            <activity
                android:name="com.example.settingdemo.MainActivity"
                android:label="@string/app_name" >
                <intent-filter>
                    <action android:name="android.intent.action.MAIN" />
    
                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>
            <activity android:name="com.example.settingdemo.SettingActivity"></activity>
            <activity android:name="com.example.settingdemo.AboutActivity"></activity>
        </application>
    
    </manifest>

至此，本文已完成，大家可以试试。

源代码下载链接：[http://download.csdn.net/detail/a123demi/7564135][http_download.csdn.net_detail_a123demi_7564135]

[Center]: /images/20220823/90e013fe524c4193a2435964ded659b0.png
[Center 1]: https://img-blog.csdn.net/20140628151942828?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvYTEyM2RlbWk=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center
[Center 2]: /images/20220823/e3e22450256547cb99b5099ecb321f95.png
[http_download.csdn.net_detail_a123demi_7564135]: http://download.csdn.net/detail/a123demi/7564135