就我而言，我试图用其他答案来解决这个问题，但没有结果。我无意中发现，空标签几乎从未显示(Android Studio 1.4)。因此，尝试在TAG中放入任何字母(空格无效)。

Log.wtf("x", "Android Studio Team, solve this, please!");

在android Studio应用程序中，您需要单击调试应用程序选项(Shift+f9)以调试模式运行并启用LogCat。

检查log标记中是否有空格。如果标签由空格组成，则删除空格，然后运行。您将能够查看日志。

我刚把它修好了。在DDMS显示的最右边寻找恢复Devices Logcat视图和ADB视图的小图标。

When the DDMS first came up with both the "ADB Logs" and the "Devices | logcat" tab showing. The "Devices | logcat" is the one that should be showing the device output, but was blank. Somehow I managed to hide one or the other of those tabs, I forget exactly how. But, off to the right there was a tiny icon that said "Restore ADB" view, and I clicked it and it came up. Then there was another tiny icon that said "Restore Devices logcat view". I clicked that, and all of a sudden it appeared and was showing the device output again.

在我的例子中，我从右边的小下拉列表中删除了“image”。在那之后一切都很好。这是因为它将在日志中搜索搜索框中的关键字，因此如果没有找到任何匹配项，它将返回空白

在我的情况下，我发送空标签，即

Log.d("","My Log");

而是发送一个标记名称

Log.d("Class name","My Log");

希望它能帮助到别人