Is there a way to have read access to history stack?

This is actually a very simple thing: I need to know if there is any of MY activities in the history stack? I'm not talking about other apps, just my own app. And I don't even need to know what are they or how many of them, I just need to know IF THERE IS ANY? Is there a way to achieve this? (ActivityManager.getRunningTasks().topActivity() is not for this purpose.)

(I'm implementing a backward/forward feature, as seen in many browsers. At first I tried to manage my own history stack and not use Android's at all. So I used noHistory=true for all activities in the manifest. This leads to the problem that the app's behavior is weird when it comes to the interacting with other apps or the Launcher. Now I tried to utilize Android's history stack for Backward operation, but my own stack for Foreward. But then it hits an unexpcted problem. .... Not just that, there is this security consideration in the app so that I can't let the user go back to any activity if the file has been locked up. I have to have total control over the stack.

Having been bothered by Android's activity life-cycle model and the history stack for several days. Extremely inflexible. How can they assume that all applications all activities in the world behave in the way they imagined in the lab!!!??? Seeing lots of people asking questions on the Internet in this area, and it seems to me everybody hit a dead end and then try to find some work-around, or compromise, or might as well change the spec. Android has been around for 3 years now, but they still didn't do anything to make it more flexible. I guess it must be a very fundamental thing in the design since Day One so that they know about the problem, but they can't do anything about it. Call it a wrong design.)

(And this non-blocking, non-synchronize dialog/message boxes. I don't know how they come up with this design. Whenever you want the user to confirm something, you have to break the program flow into several parts. This undoubtedly makes the program difficult to write and impossbile开发者_如何学运维 to maintain! If you have a series of questions one dependent on another, you might as well limplement a state machine.)

If you use Fragments in SDK level 11 and higher (so Honeycomb and certain Gingerbread levels), you can explicitly manage the stack. For regular Activities, you really don't have access to the stack, so you're out of luck there. You could possibly implement a personal stack using an application-level stack: storing the Intents you're using to launch Activities so you can move forward and then returning another Intent with the configuration data for each Activity (when each Activity finish()es you pass this state in the onActivityResult call back).

It would be very messy though.

Since you create and finish the activities, you should be aware of what is on the stack at runtime. Generally, you can control the stack pretty well. Take a look at the ApiDemo revolving around manipulating the stack.