安卓: Intercept onKeyDown()和onKeyUp()

Question

我想截取硬件键盘上的按键事件。例如，当用户按下"a“时，我不希望它被写在EditText中。因此，当按下并释放"a"-key时，我返回true，但它无论如何都是用EditText编写的。怎么啦？

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    switch (keyCode) {
        case KeyEvent.KEYCODE_A:
            //Here it logs correct, but the letter appears in the EditText anyway
            Log.d("Textboard","A");
            return true;

        default:
            return super.onKeyDown(keyCode, event);
    }
}

@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
    switch (keyCode) {
        case KeyEvent.KEYCODE_A:
            //Here it logs correct, but the letter appears in the EditText anyway
            Log.d("Textboard","A");
            return true;

        default:
            return super.onKeyUp(keyCode, event);
    }
}

Answer 1

活动的onKeyXXX()调用晚于EditText的onKeyXXX()。

如果你想拦截它，只需覆盖dispatchKeyEvent()即可。