android 监听

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // TODO Auto-generated method stub
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            Toast.makeText(this, "后退键", Toast.LENGTH_SHORT).show();
            return true;
        } else if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) {
            Toast.makeText(this, "声音+", Toast.LENGTH_SHORT).show();
            return false;
        } else if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
            Toast.makeText(this, "声音-", Toast.LENGTH_SHORT).show();
            return false;
        } else if (keyCode == KeyEvent.KEYCODE_VOLUME_MUTE) {
            Toast.makeText(this, "静音", Toast.LENGTH_SHORT).show();
            return false;
        } else if (keyCode == KeyEvent.KEYCODE_HOME) {
            Toast.makeText(this, "Home", Toast.LENGTH_SHORT).show();
            return true;
        }
        return super.onKeyDown(keyCode, event);
    }

        mWpesBundleCode.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

            }
            @Override
            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
                Toast.makeText(WpesDeliverActivity.this, mWpesBundleCode.getText().toString(), Toast.LENGTH_SHORT).show();
            }

            @Override
            public void afterTextChanged(Editable editable) {

            }
        });