如何在Android中使用onKeyDown捕获应用程序切换键？

How to capture app switch key using onKeyDown in Android?

我正在尝试在android 3.1和4.0上捕获应用程序切换键和主键，但似乎不起作用。

这是我在做什么

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@Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
if (KeyCode == KeyEvent.KEYCODE.KEYCODE_APP_SWITCH && event.getRepeatCount() == 0)
{
Log.d ("onkeydown","app switch key");
}
else if (KeyCode == KeyEvent.KEYCODE.KEYCODE_HOME && event.getRepeatCount() == 0)
{
Log.d ("onkeydown","home key");
}
//EDIT:
return super.onKeyDown(keyCode, event);
}

我的log.d语句未打印。是否可以捕获这两个键？

使用正确的返回语句更新代码

嗯

好吧，不，你不能。

public static final int KEYCODE_HOME

Since: API Level 1

Key code constant: Home key.

This key is handled by the framework and is never delivered to applications.

http://developer.android.com/reference/android/view/KeyEvent.html

相关讨论

可以使用反射来实现。

它在类android.os.ServiceManager下具有辅助符号com.android.internal.statusbar.IStatusBarService，并且包含toggleRecentApps方法

也可以在这里尝试这种方法

super.onKeyDown(keyCode，event)丢失了，我认为您应该尝试以下操作：

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@Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
super.onKeyDown(keyCode, event);

if (KeyCode == KeyEvent.KEYCODE.KEYCODE_APP_SWITCH && event.getRepeatCount() == 0)
{
Log.d ("onkeydown","app switch key");
}
else if (KeyCode == KeyEvent.KEYCODE.KEYCODE_HOME && event.getRepeatCount() == 0)
{
Log.d ("onkeydown","home key");
}
return true;
}

使用switch语句执行相同的操作：

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@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
super.onKeyDown(keyCode, event);
switch(keyCode)
{
case KeyEvent.KEYCODE_CAMERA:
Toast.makeText(ListViewActivity.this,"Pressed Camera Button", Toast.LENGTH_SHORT).show();
return true;
case KeyEvent.KEYCODE_1:
Toast.makeText(ListViewActivity.this,"Pressed 1", Toast.LENGTH_SHORT).show();
return true;
case KeyEvent.KEYCODE_HOME:
Toast.makeText(ListViewActivity.this,"Pressed Home Button", Toast.LENGTH_SHORT).show();
return true;

case KeyEvent.KEYCODE_BACK:
Toast.makeText(ListViewActivity.this,"Pressed Back Button", Toast.LENGTH_SHORT).show();
finish();
return true;
}

return false;
}