一、减少启动时间
启动时间是Launcher用户第一印象的决定因素。如果启动过程缓慢,用户会觉得设备有点慢。下面是一些减少启动时间的方法:1、精简Launcher的初始化流程。Launcher初始化流程通常包括加载和渲染UI、加载应用程序和小部件等。可以对初始化流程进行优化,例如,延迟加载一些复杂的内容。
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (isFirstStartup()) {
setContentView(R.layout.splash_screen);
} else {
setContentView(R.layout.main_activity);
}
}
2、异步加载应用程序和小部件。Android提供了一些工具来处理异步任务,例如AsyncTask和Loader。通过异步加载应用程序和小部件,可以缩短初始启动的时间。
public class AppLoaderTask extends AsyncTask
> {
private PackageManager mPackageManager;
private Context mContext;
private AppLoaderListener mListener;
public AppLoaderTask(Context context, AppLoaderListener listener) {
mContext = context;
mPackageManager = context.getPackageManager();
mListener = listener;
}
@Override
protected List
doInBackground(Void... params) {
List
apps = new ArrayList<>();
Intent intent = new Intent(Intent.ACTION_MAIN, null);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
List
resolveInfos = mPackageManager.queryIntentActivities(intent, 0);
for (ResolveInfo resolveInfo : resolveInfos) {
AppInfo appInfo = new AppInfo();
appInfo.icon = resolveInfo.loadIcon(mPackageManager);
appInfo.label = resolveInfo.loadLabel(mPackageManager);
appInfo.packageName = resolveInfo.activityInfo.packageName;
appInfo.activityName = resolveInfo.activityInfo.name;
apps.add(appInfo);
}
Collections.sort(apps, new AppInfoComparator());
return apps;
}
@Override
protected void onPostExecute(List
result) { super.onPostExecute(result); mListener.onAppsLoaded(result); } public interface AppLoaderListener { void onAppsLoaded(List
apps); } }
二、提高用户交互性
用户交互性是Launcher的核心。下面是一些提高用户交互性的方法:1、提供可定制的主屏幕。让用户自定义主屏幕的布局、背景和小部件能够提高用户满意度。可以为用户提供一个向导来帮助他们设置他们的主屏幕。
Choose a wallpaper
Choose widgets
Choose layout
2、提供智能小部件。通过高度可定制的小部件,使用户能够快速访问最常用的信息。例如,提供一个天气小部件,可以在主屏幕上显示天气预报。
public class WeatherWidget extends AppWidgetProvider {
@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.widget_weather);
WeatherInfo info = WeatherUtils.getWeatherInfo(context);
remoteViews.setTextViewText(R.id.widget_temperature, info.temperature);
remoteViews.setImageViewBitmap(R.id.widget_icon, info.icon);
appWidgetManager.updateAppWidget(appWidgetIds, remoteViews);
}
}
三、提高应用程序启动速度
应用程序启动速度是用户体验的关键。下面是一些提高应用程序启动速度的方法:1、采用预加载技术。一旦Launcher启动,就开始预加载应用程序。通过预加载应用程序,可以缩短应用程序的启动时间。
public class AppPreloadTask extends AsyncTask
{
private PackageManager mPackageManager;
private Context mContext;
public AppPreloadTask(Context context) {
mContext = context;
mPackageManager = context.getPackageManager();
}
@Override
protected Void doInBackground(Void... params) {
List
resolveInfos = mPackageManager.queryIntentActivities(new Intent(Intent.ACTION_MAIN, null).addCategory(Intent.CATEGORY_LAUNCHER), 0);
for (ResolveInfo resolveInfo : resolveInfos) {
mPackageManager.getLaunchIntentForPackage(resolveInfo.activityInfo.packageName);
}
return null;
}
}
2、采用应用程序缓存。当应用程序第一次启动时,Launcher会将应用程序缓存到内存中。下次用户打开应用程序时,可以更快地启动它。
public class AppCache {
private List
mAppInfos;
public AppCache(Context context) {
mAppInfos = new ArrayList<>();
loadApps(context);
}
private void loadApps(Context context) {
PackageManager packageManager = context.getPackageManager();
Intent intent = new Intent(Intent.ACTION_MAIN, null);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
List
resolveInfos = packageManager.queryIntentActivities(intent, 0);
for (ResolveInfo resolveInfo : resolveInfos) {
AppInfo appInfo = new AppInfo();
appInfo.icon = resolveInfo.loadIcon(packageManager);
appInfo.label = resolveInfo.loadLabel(packageManager);
appInfo.packageName = resolveInfo.activityInfo.packageName;
appInfo.activityName = resolveInfo.activityInfo.name;
appInfo.intent = packageManager.getLaunchIntentForPackage(appInfo.packageName);
mAppInfos.add(appInfo);
}
Collections.sort(mAppInfos, new AppInfoComparator());
}
public List
getApps() {
return mAppInfos;
}
}
四、提供更多的扩展性
提供更多的扩展性能够使Launcher更加强大。下面是一些扩展Launcher的方法:1、提供第三方主题支持。提供第三方主题支持可以使用户更换主题,从而使Launcher更具个性化。
public class ThemeManager {
private static List
sThemes = new ArrayList<>();
static {
sThemes.add(new ThemeInfo("Spring", R.drawable.spring_wallpaper, R.style.SpringTheme));
sThemes.add(new ThemeInfo("Summer", R.drawable.summer_wallpaper, R.style.SummerTheme));
sThemes.add(new ThemeInfo("Autumn", R.drawable.autumn_wallpaper, R.style.AutumnTheme));
sThemes.add(new ThemeInfo("Winter", R.drawable.winter_wallpaper, R.style.WinterTheme));
}
public static List
getThemes() {
return sThemes;
}
public static void applyTheme(Activity activity, ThemeInfo themeInfo) {
activity.setTheme(themeInfo.style);
ImageView wallpaperView = (ImageView) activity.getWindow().getDecorView().findViewById(android.R.id.content);
wallpaperView.setImageResource(themeInfo.wallpaper);
}
}
2、提供第三方小部件支持。提供第三方小部件支持可以让用户使用更加丰富的小部件。
public class WeatherWidgetProvider extends AppWidgetProvider {
private static final String ACTION_WEATHER_UPDATE = "com.example.action.WEATHER_UPDATE";
@Override
public void onReceive(Context context, Intent intent) {
super.onReceive(context, intent);
if (ACTION_WEATHER_UPDATE.equals(intent.getAction())) {
AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
int[] appWidgetIds = appWidgetManager.getAppWidgetIds(new ComponentName(context, getClass()));
onUpdate(context, appWidgetManager, appWidgetIds);
}
}
}