如何通过蓝牙Android Studio发送消息

Question

我创建了一个带有20个按钮的系统键盘，我想分配给一个键，通过蓝牙以Toast的形式发送消息。谁能建议该怎么做？其他电话是否也需要安装此应用程序和键盘？我还没有代码，但是在键上还有其他操作，例如：

@Override
    public void onKey(int primaryCode, int[] keyCodes) {

        InputConnection ic = getCurrentInputConnection();
        if (ic == null) return;
        switch (primaryCode) {
            case Keyboard.KEYCODE_DELETE:
                CharSequence selectedText = ic.getSelectedText(0);
                if (TextUtils.isEmpty(selectedText)) {
                    // no selection, so delete previous character
                    ic.deleteSurroundingText(1, 0);
                } else {
                    // delete the selection
                    ic.commitText("", 1);
                }
                break;
            case 53:
                Toast.makeText(getApplicationContext(), "Toast", Toast.LENGTH_SHORT).show();
                break;
            case 55:
                NfcManager manager = (NfcManager) getSystemService(Context.NFC_SERVICE);
                NfcAdapter adapter = manager.getDefaultAdapter();
                if (adapter != null && adapter.isEnabled()) {
                    Toast.makeText(MyInputMethodService.this, "NFC ON!", Toast.LENGTH_LONG).show();
                } else {
                    Toast.makeText(MyInputMethodService.this, "NFC OFF!", Toast.LENGTH_LONG).show();
                }
                break;