如何从TabHost活动返回结果（startActivityForResult）？ [英] How to return a result (startActivityForResult) from a TabHost Activity?

问题描述

我有3个班在我的例子： A类，主要活动。 A类调用startActivityForResult：

I have 3 classes in my example: Class A, the main activity. Class A calls a startActivityForResult:

Intent intent = new Intent(this, ClassB.class);
startActivityForResult(intent, "STRING");

B类，这个类是一个TabActivity：

Class B, this class is a TabActivity:

Intent intent = new Intent(this, ClassC.class);
tabHost.addTab...

C类，这个类是一个普通的活动：

Class C, this class is a regular Activity:

Intent intent = this.getIntent();
intent.putExtra("SOMETHING", "EXTRAS");
this.setResult(RESULT_OK, intent);
finish();

onActivityResult被称为A级，但结果code是 RESULT_CANCELED 而不是 RESULT_OK 和返回的意图是空。我如何返回的东西从里面TabHost的活动？

onActivityResult is called in Class A, but the resultCode is RESULT_CANCELED instead of RESULT_OK and the returned intent is null. How do I return something from the Activity inside a TabHost?

我意识到，问题是，我的C类实际上是B级的内部运行，而B类是什么返回 RESULT_CANCELED 返回到A级。我刚不知道工作尚未各地。

I realize that the problem is that my Class C is actually running inside of Class B, and Class B is what is returning the RESULT_CANCELED back to Class A. I just don't know a work around yet.

推荐答案

哦，上帝！花几个小时，下载了Android源后，我终于得出一个解决方案。

Oh, god! After spending several hours and downloading the Android sources, I have finally come to a solution.

如果你看一下Activity类，你会看到，完成（）方法只发回的结果，如果有一个 mParent 属性设置为空。否则结果将丢失。

If you look at the Activity class, you will see, that finish() method only sends back the result if there is a mParent property set to null. Otherwise the result is lost.

public void finish() {
    if (mParent == null) {
        int resultCode;
        Intent resultData;
        synchronized (this) {
            resultCode = mResultCode;
            resultData = mResultData;
        }
        if (Config.LOGV) Log.v(TAG, "Finishing self: token=" + mToken);
        try {
            if (ActivityManagerNative.getDefault()
                .finishActivity(mToken, resultCode, resultData)) {
                mFinished = true;
            }
        } catch (RemoteException e) {
            // Empty
        }
    } else {
        mParent.finishFromChild(this);
    }
}

所以我的解决办法是将结果向父活动，如果present，这样的：

So my solution is to set result to the parent activity if present, like that:

Intent data = new Intent();
 [...]
if (getParent() == null) {
    setResult(Activity.RESULT_OK, data);
} else {
    getParent().setResult(Activity.RESULT_OK, data);
}
finish();

我希望这将是有益的，如果有人再寻找这个问题的解决方法。

I hope that will be helpful if someone looks for this problem workaround again.

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