Android View使用startDragAndDrop 异常 Unable to initiate drag

设备环境：Android13

源码来源：android-13.0.0_r3

View在使用startDragAndDrop出现如下异常

shell 复制代码

01-01 12:44:12.243 24031 24031 E View    : Unable to initiate drag
01-01 12:44:12.243 24031 24031 E View    : java.lang.IllegalStateException: Need to validate before calling identify is cleared
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Parcel.createExceptionOrNull(Parcel.java:3019)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Parcel.createException(Parcel.java:2995)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Parcel.readException(Parcel.java:2978)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Parcel.readException(Parcel.java:2920)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.IWindowSession$Stub$Proxy.performDrag(IWindowSession.java:1678)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.View.startDragAndDrop(View.java:27325)
01-01 12:44:12.243 24031 24031 E View    :      at com.zhonghong.ac.view.style.adapter.AcStyleAdapter$1.onLongClick(AcStyleAdapter.java:91)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.View.performLongClickInternal(View.java:7586)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.View.performLongClick(View.java:7544)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.View.performLongClick(View.java:7562)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.View$CheckForLongPress.run(View.java:29297)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Handler.handleCallback(Handler.java:942)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Handler.dispatchMessage(Handler.java:99)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Looper.loopOnce(Looper.java:201)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Looper.loop(Looper.java:288)
01-01 12:44:12.243 24031 24031 E View    :      at android.app.ActivityThread.main(ActivityThread.java:7944)
01-01 12:44:12.243 24031 24031 E View    :      at java.lang.reflect.Method.invoke(Native Method)
01-01 12:44:12.243 24031 24031 E View    :      at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
01-01 12:44:12.243 24031 24031 E View    :      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:942)
01-01 12:44:12.243 24031 24031 E View    : Caused by: android.os.RemoteException: Remote stack trace:
01-01 12:44:12.243 24031 24031 E View    :      at com.android.server.wm.Session.validateAndResolveDragMimeTypeExtras(Session.java:369)
01-01 12:44:12.243 24031 24031 E View    :      at com.android.server.wm.Session.performDrag(Session.java:324)
01-01 12:44:12.243 24031 24031 E View    :      at android.view.IWindowSession$Stub.onTransact(IWindowSession.java:876)
01-01 12:44:12.243 24031 24031 E View    :      at com.android.server.wm.Session.onTransact(Session.java:175)
01-01 12:44:12.243 24031 24031 E View    :      at android.os.Binder.execTransactInternal(Binder.java:1280)
01-01 12:44:12.243 24031 24031 E View    :

使用Demo验证功能正常😀，然后集成到应用后就抛出异常无法使用😒，在百度、谷歌、Bing上来回找原因，并且反复核对代码，终于还是没有解决🤦‍♂️

不过还在定位到了原因，这个bug有人提出了issue issuetracker.google.com/issues/2456...

原因分析

根据上面的issue最终定位到了最终根源所在👇

java 复制代码

//services/core/java/com/android/server/wm/Session.java

@Override
public IBinder performDrag(IWindow window, int flags, SurfaceControl surface, int touchSource,
        float touchX, float touchY, float thumbCenterX, float thumbCenterY, ClipData data) {
    final int callingUid = Binder.getCallingUid();
    final int callingPid = Binder.getCallingPid();
    // Validate and resolve ClipDescription data before clearing the calling identity
    validateAndResolveDragMimeTypeExtras(data, callingUid, callingPid, mPackageName);
    validateDragFlags(flags, callingUid);
    final long ident = Binder.clearCallingIdentity();
    try {
        return mDragDropController.performDrag(mPid, mUid, window, flags, surface, touchSource,
                touchX, touchY, thumbCenterX, thumbCenterY, data);
    } finally {
        Binder.restoreCallingIdentity(ident);
    }
}

/**
 * Validates the given drag flags.
 */
@VisibleForTesting
void validateDragFlags(int flags, int callingUid) {
    if (callingUid == Process.SYSTEM_UID) {
        throw new IllegalStateException("Need to validate before calling identify is cleared");
    }

    if ((flags & View.DRAG_FLAG_REQUEST_SURFACE_FOR_RETURN_ANIMATION) != 0) {
        if (!mCanStartTasksFromRecents) {
            throw new SecurityException("Requires START_TASKS_FROM_RECENTS permission");
        }
    }
}

/**
 * Validates the given drag data.
 */
@VisibleForTesting
void validateAndResolveDragMimeTypeExtras(ClipData data, int callingUid, int callingPid,
        String callingPackage) {
    if (callingUid == Process.SYSTEM_UID) {
        throw new IllegalStateException("Need to validate before calling identify is cleared");
    }
    final ClipDescription desc = data != null ? data.getDescription() : null;
    if (desc == null) {
        return;
    }
    //省略其他...
}

我去无语了，系统进程应用这是直接不让用啊🤷‍♂️

java 复制代码

if (callingUid == Process.SYSTEM_UID) {
    throw new IllegalStateException("Need to validate before calling identify is cleared");
}

看下面有人反馈该问题已经修复了，随后我去看了一下Android14的源码，好家伙不拦截了🤢

Android14 Session

结尾

所以主要原因是我的应用是系统应用导致在当前版本上无法使用，初步来看是在Android13及以下都无法使用！

算了，不搞了，也不想打扰framework，我也不涉及多窗口之类的拖拽，还是使用RecyclerView吧🧨