startActivityForResult不返回结果，请检查AndroidManifest中的描述，是否对该Activity设置了：launchMode="singleTask",
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For example, if the activity you are launching uses the singleTask launch mode,
it will not run in your task and thus you will immediately receive a cancel result.startActivityForResult不返回结果,布布扣,bubuko.com
原文：http://blog.csdn.net/h3c4lenovo/article/details/38322489