android - Settings.Global.putInt() 不会立即生效

Question

我开发了一个应用程序并将其转换为系统应用程序。在这个应用程序中，我想更改三个全局变量:ANIMATOR_DURATION_SCALE、WINDOW_ANIMATION_SCALE 和 TRANSITION_ANIMATION_SCALE。但是在我通过我的应用程序修改值后，我必须再次进入设置(这是由谷歌开发的系统应用程序)应用程序才能让修改生效，否则修改将不起作用。这是我的代码:

  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_SETTINGS" />
<uses-permission android:name="android.permission.SET_ANIMATION_SCALE" />

<!--system app-->
<uses-permission android:name="android.permission.WRITE_SECURE_SETTINGS" />

我在选中 Switch 时修改 MainActivity 中的值

 public void changeAnimationSettings(boolean isChecked) {

    int result1 = isChecked ? 0 : 1;
    Settings.Global.putInt(getContentResolver(), Settings.Global.ANIMATOR_DURATION_SCALE, result1);
    Settings.Global.putInt(getContentResolver(), Settings.Global.WINDOW_ANIMATION_SCALE, result1);
    Settings.Global.putInt(getContentResolver(), Settings.Global.TRANSITION_ANIMATION_SCALE, result1);

    Log.i(TAG, "---->>ANIMATOR_DURATION_SCALE: " + Settings.Global.getString(getContentResolver(), Settings.Global.ANIMATOR_DURATION_SCALE));
    Log.i(TAG, "---->>WINDOW_ANIMATION_SCALE: " + Settings.Global.getString(getContentResolver(), Settings.Global.WINDOW_ANIMATION_SCALE));
    Log.i(TAG, "---->>TRANSITION_ANIMATION_SCALE " + Settings.Global.getString(getContentResolver(), Settings.Global.TRANSITION_ANIMATION_SCALE));
}

并且日志显示代码修改值成功。

Answer 1

使用这个“设置应用魔法”(original taken from AOSP source)立即看到变化:

SystemPropPoker().execute()

同时添加这个类

class SystemPropPoker extends AsyncTask<Void, Void, Void> {

private static final String TAG = SystemPropPoker.class.getName();

@SuppressWarnings("unchecked")
@Override
protected Void doInBackground(@NonNull Void... params) {
    String[] services;
    try {
        Class serviceManagerClass = Class.forName("android.os.ServiceManager");
        Method listServicesMethod = serviceManagerClass.getMethod("listServices");
        services = (String[]) listServicesMethod.invoke(null);
        for (String service : services) {
            Method checkServiceMethod = serviceManagerClass.getMethod("checkService", String.class);
            IBinder obj = (IBinder) checkServiceMethod.invoke(null, service);
            if (obj != null) {
                Parcel data = Parcel.obtain();
                final int SYSPROPS_TRANSACTION = ('_'<<24)|('S'<<16)|('P'<<8)|'R'; //copy from source code in android.os.IBinder.java
                try {
                    obj.transact(SYSPROPS_TRANSACTION, data, null, 0);
                } catch (Exception e) {
                    Log.i(TAG, "Someone wrote a bad service '" + service
                            + "' that doesn't like to be poked: " + e);
                }
                data.recycle();
            }
        }
    } catch (ClassNotFoundException | NoSuchMethodException | InvocationTargetException | IllegalAccessException e) {
        e.printStackTrace();
    }
    return null;
}

引用:How to easily "Show Layout bounds" for Android debugging?