Android: How do I start an activity from the preferences menu?… here is a solution to the problem.
Android: How do I start an activity from the preferences menu?
This is Android Live Wallpaper.
. LiveWallpaperSettings is the primary activity with setting preferences.
. AboutActivity is a simple conversational activity.
I have the following code:
An androidManifest .xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="ru.fph.iiidlayer"
android:versionName="1.2"
android:versionCode="1">
<uses-sdk android:minSdkVersion="3" android:targetSdkVersion="7" />
<uses-feature android:name="ru.fph.iiidlayer" />
<application android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:debuggable="true" >
<supports-screen android:anyDensity="true" />
<service android:name=". LiveWallpaper"
android:label="@string/app_name"
android:icon="@drawable/ic_launcher"
android:permission="android.permission.BIND_WALLPAPER" >
<intent-filter>
<action android:name="android.service.wallpaper.WallpaperService" />
</intent-filter>
<meta-data android:name="android.service.wallpaper"
android:resource="@xml/livewallpaper" />
</service>
<activity android:label="@string/app_name"
android:name=". LiveWallpaperSettings"
android:theme="@android:style/Theme.Light.WallpaperSettings"
android:exported="true"
android:icon="@drawable/ic_launcher">
</activity>
<activity android:theme="@android:style/Theme.Dialog"
android:label="@string/livewallpaper_about_title"
android:name=". AboutActivity">
<intent-filter>
<action android:name="ABOUT_ACTION" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
<supports-screens android:anyDensity="true"
android:smallScreens="true"
android:normalScreens="true"
android:largeScreens="true"
android:resizeable="true" />
</manifest>
livewallpaper_settings.xml:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
android:title="@string/livewallpaper_settings"
android:key="livewallpaper_settings">
<Preference android:key="livewallpaper_image"
android:title="@string/livewallpaper_image_title"
android:summary="@string/livewallpaper_image_summary" />
<ListPreference
android:key="livewallpaper_sens"
android:title="@string/livewallpaper_sens_title"
android:summary="@string/livewallpaper_sens_summary"
android:entries="@array/livewallpaper_sens_names"
android:entryValues="@array/livewallpaper_sens_prefix"/>
<Preference android:key="livewallpaper_about"
android:title="@string/livewallpaper_about_title"
android:summary="@string/livewallpaper_about_summary">
<intent android:action="ABOUT_ACTION" />
</Preference>
</PreferenceScreen>
LivewallpaperSettings.java:
package ru.fph.iiidlayer;
import ru.fph.iiidlayer.R;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.preference.Preference;
import android.preference.Preference.OnPreferenceClickListener;
import android.preference.PreferenceActivity;
import android.provider.MediaStore;
public class LiveWallpaperSettings extends PreferenceActivity implements SharedPreferences.OnSharedPreferenceChangeListener, OnPreferenceClickListener
{
Preference gallery_pref, about_pref;
Intent gallery, about;
String gallery_key = "livewallpaper_image";
String about_key = "livewallpaper_about";
@Override
protected void onCreate(Bundle icicle)
{
super.onCreate(icicle);
getPreferenceManager().setSharedPreferencesName(LiveWallpaper.SHARED_PREFS_NAME);
addPreferencesFromResource(R.xml.livewallpaper_settings);
getPreferenceManager().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
gallery_pref = findPreference(gallery_key);
gallery = new Intent();
gallery.setType("image/*");
gallery.setAction(gallery. ACTION_GET_CONTENT);
gallery_pref.setOnPreferenceClickListener(this);
about_pref = findPreference(about_key);
about = new Intent(this, AboutActivity.class);
about_pref.setOnPreferenceClickListener(this);
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == RESULT_OK)
if(requestCode == 1) {
String src = getRealPathFromURI(data.getData());
LiveWallpaper.backgroundSrc = src;
}
}
public boolean onPreferenceClick(Preference pr) {
if(pr.getKey().equals(gallery_key)) {
startActivityForResult(Intent.createChooser(gallery, getString(R.string.livewallpaper_gallery_title)),1);
}
/* if(pr.getKey().equals(about_key)) {
startActivity(about);
} */
return false;
}
public String getRealPathFromURI(Uri contentUri) {
String [] proj={MediaStore.Images.Media.DATA};
Cursor cursor = managedQuery(contentUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
@Override
protected void onResume()
{
super.onResume();
}
@Override
protected void onDestroy()
{
getPreferenceManager().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
super.onDestroy();
}
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key)
{
}
}
AboutActivity.java:
package ru.fph.iiidlayer;
import android.app.Activity;
import android.os.Bundle;
public class AboutActivity extends LiveWallpaperSettings {
@Override
protected void onCreate(Bundle icicle)
{
super.onCreate(icicle);
setContentView(R.layout.about);
}
@Override
protected void onResume()
{
super.onResume();
}
@Override
protected void onDestroy()
{
super.onDestroy();
}
}
Log:
12-30 11:11:26.967: D/AndroidRuntime(228): Shutting down VM
12-30 11:11:26.967: W/dalvikvm(228): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
12-30 11:11:26.967: E/AndroidRuntime(228): Uncaught handler: thread main exiting due to uncaught exception
12-30 11:11:26.987: E/AndroidRuntime(228): java.lang.RuntimeException: Unable to start activity ComponentInfo{ru.fph.iiidlayer/ru.fph.iiidlayer.AboutActivity}: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android. R.id.list'
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2496)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ActivityThread.access$2200(ActivityThread.java:119)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.os.Handler.dispatchMessage(Handler.java:99)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.os.Looper.loop(Looper.java:123)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ActivityThread.main(ActivityThread.java:4363)
12-30 11:11:26.987: E/AndroidRuntime(228): at java.lang.reflect.Method.invokeNative(Native Method)
12-30 11:11:26.987: E/AndroidRuntime(228): at java.lang.reflect.Method.invoke(Method.java:521)
12-30 11:11:26.987: E/AndroidRuntime(228): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
12-30 11:11:26.987: E/AndroidRuntime(228): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
12-30 11:11:26.987: E/AndroidRuntime(228): at dalvik.system.NativeStart.main(Native Method)
12-30 11:11:26.987: E/AndroidRuntime(228): Caused by: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android. R.id.list'
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ListActivity.onContentChanged(ListActivity.java:236)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.preference.PreferenceActivity.onContentChanged(PreferenceActivity.java:160)
12-30 11:11:26.987: E/AndroidRuntime(228): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:201)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.Activity.setContentView(Activity.java:1622)
12-30 11:11:26.987: E/AndroidRuntime(228): at ru.fph.iiidlayer.AboutActivity.onCreate(AboutActivity.java:11)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-30 11:11:26.987: E/AndroidRuntime(228): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459)
12-30 11:11:26.987: E/AndroidRuntime(228): ... 11 more
12-30 11:11:27.017: I/Process(52): Sending signal. PID: 228 SIG: 3
12-30 11:11:27.017: I/dalvikvm(228): threadid=7: reacting to signal 3
12-30 11:11:27.017: I/dalvikvm(228): Wrote stack trace to '/data/anr/traces.txt'
The gallery setting preferences are absolutely correct. However, when I try to call AboutActivity in the same way (the comments section in LivewallpaperSettings.java), the app crashes when I tap on preferences.
P.S. I made this example through other decompiled applications
What am I doing wrong?
Solution
The problem is that AboutActivity extends LiveWallpaperSettings, which itself is a subclass of PreferenceActivity and therefore a subclass of ListActivity. The ListActivity class requires an id in the layout file for android. R.id.list's ListView.
I don’t think you need to extend AboutActivity with LiveWallpaperSettings. Use a normal activity instead.