我想知道在某些情况下是否可以覆盖后退和主页按钮的操作。
是的,你可以做覆盖Home
按钮。
我开发了一个禁用硬按钮的应用程序,你可以看看。我采用了一个切换按钮,它可以锁定除电源按钮以外的所有硬按钮
public class DisableHardButton extends Activity {
/** Called when the activity is first created. */
TextView mTextView;
ToggleButton mToggleButton;
boolean isLock=false;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mTextView=(TextView) findViewById(R.id.tvInfo);
mToggleButton=(ToggleButton) findViewById(R.id.btnLock);
mToggleButton.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
isLock=isChecked;
onAttachedToWindow();
}
});
}
@Override
public boolean dispatchKeyEvent(KeyEvent event) {
if ( (event.getKeyCode() == KeyEvent.KEYCODE_HOME) && isLock) {
mTextView.setText("KEYCODE_HOME");
return true;
}
else
return super.dispatchKeyEvent(event);
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
if( (keyCode==KeyEvent.KEYCODE_BACK) && isLock)
{
mTextView.setText("KEYCODE_BACK");
return true;
}
else
return super.onKeyDown(keyCode, event);
}
@Override
public void onAttachedToWindow()
{
System.out.println("Onactivity attached :"+isLock);
if(isLock)
{
this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);
super.onAttachedToWindow();
}
else
{
this.getWindow().setType(WindowManager.LayoutParams.TYPE_APPLICATION);
super.onAttachedToWindow();
}
}
}
主要的.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/tvInfo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<ToggleButton
android:id="@+id/btnLock"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textOff="UnLocked"
android:textOn="Locked" />
</LinearLayout>