聊聊Activity那些事

 public abstract AssetManager getAssets();


public abstract Resources getResources();


public abstract PackageManager getPackageManager();


public abstract ContentResolver getContentResolver();


public abstract Context getApplicationContext();


public final CharSequence getText(@StringRes int resId) 

{

    return getResources().getText(resId);

}


public final String getString(@StringRes int resId) 

{

    return getResources().getString(resId);

}


public final int getColor(int id) 

{

    return getResources().getColor(id, getTheme());

}


public final Drawable getDrawable(int id) 

{

    return getResources().getDrawable(id, getTheme());

}


public abstract String getPackageName();


public abstract File getSharedPrefsFile(String name);


public abstract SharedPreferences getSharedPreferences(String name,

        int mode);


public abstract void startActivity(Intent intent);



public void startActivityForResult(

        @NonNull String who, Intent intent, int requestCode, @Nullable Bundle options) 

{

    throw new RuntimeException("This method is only implemented for Activity-based Contexts. "

            + "Check canStartActivityForResult() before calling.");

}


public abstract void sendBroadcast(Intent intent);


public abstract Intent registerReceiver(@Nullable BroadcastReceiver receiver, IntentFilter filter);


public abstract void unregisterReceiver(BroadcastReceiver receiver);


public abstract ComponentName startService(Intent service);


public abstract boolean stopService(Intent service);


public abstract boolean bindService(Intent service, @NonNull ServiceConnection conn, @BindServiceFlags int flags);


public abstract void unbindService(@NonNull ServiceConnection conn);


public abstract Object getSystemService(@ServiceName @NonNull String name);