android 屏蔽home键操作

1 重写onAttachedToWindow

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

2 重写onKeyDown

public boolean onKeyDown(int keyCode, KeyEvent event) {  
    switch (keyCode) {  
        case KeyEvent.KeyEvent.KEYCODE_HOME:  
        Log.i(TAG,"KEYCODE_HOME");  
        return true;  
    }  
    return super.onKeyDown(keyCode, event);  
}  

3 android源码 

因为android系统自己对home键在PhoneWindowManager中做了处理，不会返回到上层应用。查看源代码：

\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;
                    }
                }
            }

4 Dialog

如果在Activity弹出dialog，在Activity设置以上2个方法是没办法屏蔽的。 
其实，原理是一样的，只是地方不一样而已。 

final Dialog dialog = new Dialog(this);  
dialog.setContentView(R.layout.mydailog);  
dialog.show();   //show应在setType之前，否则报错
dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);  
  
dialog.setOnKeyListener(new android.content.DialogInterface.OnKeyListener(){  
    @Override  
    public boolean onKey(DialogInterface dialog, int keyCode,KeyEvent event) {  
        switch (keyCode) {  
            case KeyEvent.KEYCODE_HOME:  
            Log.i(TAG,"KEYCODE_HOME");  
            return true;  
        }  
        return false;  
    }  
});

参考：

dialog,activity 屏蔽Home键详解

WindowManager.LayoutParams