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                            /Android
                        
                        /Android攻城狮的第一门课（入门篇）

Multiple markers at this line - overrides android.app.Activity.onCreateOptionsMenu - Call requires API level 11 (current min is 8): android.view.View#setAlpha

Multiple markers at this line
   - overrides android.app.Activity.onCreateOptionsMenu
   - Call requires API level 11 (current min is 8):
   android.view.View#setAlpha

是什么意思？