android 捕获并处理HOME键

转自：http://zhifeiji512.iteye.com/blog/1055358

1. 在activity中加上这段代码就可以屏蔽home键（onKeyDown事件会捕捉到home键）。

public void onAttachedToWindow()  
{    
       this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);       
       super.onAttachedToWindow();    
}  

2. 因为android系统自己对与home键power键在PhoneWindowManager中做了处理，不会返回到上层应用的。以下为系统源码：

\frameworks\policies\base\phone\com\android\internal\policy\impl\PhoneWindowManager.java 1089行  
   
if (code == KeyEvent.KEYCODE_HOME) {  
   
            // If a system window has focus, then it doesn't make sense  
            // right now to interact with applications.  
            WindowManager.LayoutParams attrs = win != null ? win.getAttrs() : null;  
            if (attrs != null) {  
                final int type = attrs.type;  
                if (type == WindowManager.LayoutParams.TYPE_KEYGUARD  
                        || type == WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG) {  
                    // the "app" is keyguard, so give it the key  
                    return false;  
                }  
                final int typeCount = WINDOW_TYPES_WHERE_HOME_DOESNT_WORK.length;  
                for (int i=0; i<typeCount; i++) {  
                    if (type == WINDOW_TYPES_WHERE_HOME_DOESNT_WORK[i]) {  
                        // don't do anything, but also don't pass it to the app  
                        return true;  
                    }  
                }  
            }  

type == WindowManager.LayoutParams.TYPE_KEYGUARD这一句，我们可以看到，android对于锁屏特殊判断了，所以我就模拟这个进行的实现，只是有一点，activity中重写onAttachedToWindow（）方法需要api 5以上。