首先，先喷一下张艺谋的片子，你他妈太黑了~！什么史上最干净的爱情片，我说是史上最烂的爱情片，只能把无知当纯情。拍电影拍得一点诚意都没有，只会抄韩国的爱情片，记得有一部韩国片跟你这部剧情都差不多~！你就使劲抄吧~！！浪费我160大洋，进去睡觉。
喷到这里。
首先，跟园主说一声，不好意思，此篇文章应该发布到博问区，不过我想就此问题跟大家多勾通一下，如果违规了，请撤下首页。
这一两天碰到一个问题，是一个关于ActivityGroup 的问题，因为项目需要，必须把一个自定义的PreferenceActivity 的界面嵌套在ActivityGroup 里面，可是当我嵌套在里面的时候发现了一个问题。就是PreferenceActivity 的元素不会自动更新UI，这是比较致命的，不知道为什么会出现这个问题。
查了很久，首先我怀疑是我的自定义preference写的有问题，改了一遍，然后再运行还是一样。
单独运行该 preferenceActivity 试了一下，界面可以按照自己的需求更新UI，那就是说不是我这个自定义的preference 的逻辑问题？这点还不敢确定。
那么我怀疑是 ActivityGroup 不允许底下Activity 元素的UI自动更新，那么新建一个普通的Activity 来试试，在这普通的Activity 里面只有一个按钮同样是点击之后弹出对话框然后改变按钮的字，试了一下，。更新成功。。。耶？那么说ActivityGroup 还是允许底下Activity UI 元素更新的？那么问题出在哪呢？
我又再调试跟踪了代码，确定有执行settext的代码？那是不是说preferenceActivity 和ActivityGroup有冲突？不知道所然，下面贴出我碰到问题的全部代码，由于在公司有加密软件无法将DEMO提供给大家，大家可以根据代码新建一个工程，一起来研究这个问题。
自定义的PreferenceScreenExt 源码：
package asai.cn.seekbardemo;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import android.app.Dialog;import android.content.Context;import android.content.DialogInterface;import android.content.SharedPreferences;import android.content.res.TypedArray;import android.os.Parcel;import android.os.Parcelable;import android.preference.Preference;import android.preference.PreferenceGroup;import android.preference.Preference.BaseSavedState;import android.util.AttributeSet;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.view.View.OnClickListener;import android.widget.AdapterView;import android.widget.ListView;import android.widget.RelativeLayout;import android.widget.SimpleAdapter;import android.widget.TextView;import android.widget.AdapterView.OnItemClickListener;import android.widget.TextView.SavedState; public class PreferenceScreenExt extends PreferenceGroup implements OnItemClickListener, DialogInterface.OnDismissListener { private Dialog dialog; private TextView title, summary; private RelativeLayout area; private ListView listView; List < Preference > list; private List < HashMap < String, String >> listStr; private CharSequence[] mEntries; private String mValue; private SimpleAdapter simple; public PreferenceScreenExt(Context context, AttributeSet attrs) { this (context, attrs, android.R.attr.preferenceScreenStyle); // TODO Auto-generated constructor stub } public PreferenceScreenExt(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, android.R.attr.preferenceScreenStyle); // TODO Auto-generated constructor stub int resouceId = attrs.getAttributeResourceValue( null , " Entries " , 0 ); if (resouceId > 0 ) { mEntries = getContext().getResources().getTextArray(resouceId); } } @Override protected View onCreateView(ViewGroup parent) { // TODO Auto-generated method stu View view = LayoutInflater.from(getContext()).inflate( R.layout.preference_screen, null ); area = (RelativeLayout) view.findViewById(R.id.area); title = (TextView) view.findViewById(R.id.title); summary = (TextView) view.findViewById(R.id.summary); title.setText(getTitle()); summary.setText(getPersistedString(getSummary().toString())); area.setOnClickListener( new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub showDialog(); } }); return view; } public void bindView(ListView listview) { int length = mEntries.length; int i = 0 ; listStr = new ArrayList < HashMap < String, String >> (); for (i = 0 ; i < length; i ++ ) { HashMap < String, String > map = new HashMap < String, String > (); map.put( " keyname " , mEntries[i].toString()); listStr.add(map); } simple = new SimpleAdapter(getContext(), listStr, R.layout.dialog_view, new String[] { " keyname " }, new int [] { R.id.text }); listview.setAdapter(simple); listview.setOnItemClickListener( this ); } public void showDialog() { listView = new ListView(getContext()); bindView(listView); dialog = new Dialog(getContext(), android.R.style.Theme_NoTitleBar); dialog.setContentView(listView); dialog.setOnDismissListener( this ); dialog.show(); } @Override public void onItemClick(AdapterView <?> parent, View view, int position, long id) { // TODO Auto-generated method stub mValue = listStr. get (position). get ( " keyname " ).toString(); persistString(mValue); callChangeListener(mValue); PreferenceScreenExt. this .setOnPreferenceChangeListener( new OnPreferenceChangeListener() { @Override public boolean onPreferenceChange(Preference preference, Object newValue) { // TODO Auto-generated method stub if (temp != null ) { temp.onPreferenceChange(PreferenceScreenExt. this , newValue); } return true ; } }); dialog.dismiss(); } @Override public void onDismiss(DialogInterface dialog) { // TODO Auto-generated method stub } private OnPreferenceChangeListener temp; public interface OnPreferenceChangeListener { public boolean onPreferenceChange(Preference preference, Object newValue); } public void setOnPreferenceChangeListener( OnPreferenceChangeListener preference) { this .temp = preference; } public void setValue(String value) { summary.setText(value); persistString(value); summary.invalidate(); }}
对应的XML布局文件：
dialog_view.xml <? xml version="1.0" encoding="utf-8" ?> < LinearLayout android:layout_width ="fill_parent" xmlns:android ="http://schemas.android.com/apk/res/android" android:orientation ="vertical" android:gravity ="center" android:layout_height ="fill_parent" > < TextView android:id ="@+id/text" android:layout_marginLeft ="20dp" android:textAppearance ="?android:attr/textAppearanceLarge" android:textSize ="35sp" android:layout_width ="wrap_content" android:layout_height ="wrap_content" > </ TextView > </ LinearLayout >
preference_screen.xml <? xml version="1.0" encoding="utf-8" ?> < RelativeLayout android:id ="@+id/area" android:gravity ="center_vertical" android:layout_marginTop ="5px" android:clickable ="true" xmlns:android ="http://schemas.android.com/apk/res/android" android:layout_width ="fill_parent" android:layout_height ="wrap_content" > < TextView android:id ="@+id/title" android:layout_marginLeft ="20dp" android:textAppearance ="?android:attr/textAppearanceLarge" android:textSize ="35sp" android:layout_width ="wrap_content" android:layout_height ="wrap_content" > </ TextView > < TextView android:id ="@+id/summary" android:layout_marginRight ="20dp" android:textSize ="35sp" android:textAppearance ="?android:attr/textAppearanceLarge" android:layout_alignParentRight ="true" android:layout_width ="wrap_content" android:layout_height ="wrap_content" > </ TextView > </ RelativeLayout >
XML文件夹下的XML文件：
preference.xml <? xml version="1.0" encoding="utf-8" ?> < PreferenceScreen xmlns:android ="http://schemas.android.com/apk/res/android" > < asai.cn.seekbardemo.PreferenceScreenExt Entries ="@array/country" android:title ="收音区域" android:summary ="美国" android:persistent ="true" android:key ="eeg" > </ asai.cn.seekbardemo.PreferenceScreenExt > </ PreferenceScreen >
main.java 对应代码
package asai.cn.seekbardemo;import android.app.ActivityGroup;import android.app.LocalActivityManager;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.view.Window;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.LinearLayout; public class main extends ActivityGroup implements OnClickListener { private LocalActivityManager lm; private LinearLayout layout; private Button btn, btn2; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.group); lm = getLocalActivityManager(); btn = (Button) findViewById(R.id.Button01); btn2 = (Button) findViewById(R.id.Button02); btn.setOnClickListener( this ); btn2.setOnClickListener( this ); layout = (LinearLayout) findViewById(R.id.layout); Intent intent = new Intent( this , seekBarDemo. class ); intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); Window w = lm.startActivity( " test " , intent); View v = w.getDecorView(); layout.removeAllViews(); layout.addView(v); } @Override public void onClick(View v) { // TODO Auto-generated method stub switch (v.getId()) { case R.id.Button01: Intent intent = new Intent( this , seekBarDemo. class ); intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); Window w = lm.startActivity( " test " , intent); View view = w.getDecorView(); layout.removeAllViews(); layout.addView(view); break ; case R.id.Button02: Intent in = new Intent( this , test. class ); in .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); Window win = lm.startActivity( " ww " , in ); View vw = win.getDecorView(); layout.removeAllViews(); layout.addView(vw); break ; default : break ; } }}
对应的XML布局文件：
group.xml <? xml version="1.0" encoding="utf-8" ?> < LinearLayout android:orientation ="vertical" android:layout_width ="fill_parent" android:layout_height ="fill_parent" xmlns:android ="http://schemas.android.com/apk/res/android" > < LinearLayout android:layout_width ="fill_parent" android:gravity ="center_horizontal" android:layout_height ="wrap_content" > < Button android:text ="preference界面" android:id ="@+id/Button01" android:layout_width ="wrap_content" android:layout_height ="wrap_content" ></ Button > < Button android:text ="普通" android:id ="@+id/Button02" android:layout_width ="wrap_content" android:layout_height ="wrap_content" ></ Button > </ LinearLayout > < LinearLayout android:id ="@+id/layout" android:layout_width ="fill_parent" android:layout_height ="wrap_content" ></ LinearLayout > </ LinearLayout >
PreferenceActivity 界面代码 SeekBarDemo.java：
package asai.cn.seekbardemo;import android.os.Bundle;import android.preference.Preference;import android.preference.PreferenceActivity;import android.preference.Preference.OnPreferenceChangeListener;import android.widget.TextView; public class seekBarDemo extends PreferenceActivity { private Preference eeg; /* * Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); addPreferencesFromResource(R.xml.preference); final PreferenceScreenExt pre = (PreferenceScreenExt) findPreference( " eeg " ); pre.setOnPreferenceChangeListener( new OnPreferenceChangeListener() { @Override public boolean onPreferenceChange(Preference preference, Object newValue) { // TODO Auto-generated method stub pre.setValue(String.valueOf(newValue)); return true ; } }); }}
普通的Activity 界面代码test.java：
package asai.cn.seekbardemo;import android.app.Activity;import android.app.AlertDialog;import android.content.DialogInterface;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button; public class test extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.test); final Button btn = (Button) findViewById(R.id.Button01); btn.setOnClickListener( new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub new AlertDialog.Builder(test. this ).setMessage( " 修改 " ).setTitle( " 提示 " ).setPositiveButton(android.R. string .ok, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub btn.setText( " 修改后的按钮 " ); } }).show(); } }); }}
配置文件：
AndroidManifest.xml <? xml version="1.0" encoding="utf-8" ?> < manifest xmlns:android ="http://schemas.android.com/apk/res/android" package ="asai.cn.seekbardemo" android:versionCode ="1" android:versionName ="1.0" > < application android:icon ="@drawable/icon" android:label ="@string/app_name" > < activity android:name =".main" 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 =".test" android:label ="@string/app_name" > < intent-filter > < category android:name ="android.intent.category.LAUNCHER" /> </ intent-filter > </ activity > < activity android:name =".seekBarDemo" android:label ="@string/app_name" > < intent-filter > < category android:name ="android.intent.category.LAUNCHER" /> </ intent-filter > </ activity > </ application > < uses-sdk android:minSdkVersion ="7" /> </ manifest >
希望就此问题和大家探讨一下。
转载于:https://www.cnblogs.com/TerryBlog/archive/2010/09/27/1836533.html
相关资源：数据结构—成绩单生成器