使用NFC的“有效负载" "if"中的变量陈述 [英] Use NFC "payload" variable in "if" statement

问题描述

我正在尝试使用已写入NFC标签的外部记录中的有效负载"值.我知道记录已成功写入NFC标签.我在"if"语句中使用该有效载荷"值时遇到问题.我的代码如下:

I'm attempting to use the "payload" value from an external record that I've written to an NFC tag. I know that the record has been written successfully to the NFC tag. I'm having problems using that "payload" value in an "if" statement. My code follows:

protected void onResume() {
    super.onResume();

    // read nfc tag...IS THIS WHAT WILL "READ" THE PAYLOAD VALUE THAT HAS BEEN WRITTIEN?

    if (getIntent().hasExtra(NfcAdapter.EXTRA_TAG)) {

        NdefMessage ndefMessage =       this.getNdefMessageFromIntent(getIntent());
        if(ndefMessage.getRecords().length > 0){
            NdefRecord ndefRecord = ndefMessage.getRecords()[0];
            String payload = new String(ndefRecord.getPayload());
            Toast.makeText(this, payload, Toast.LENGTH_SHORT).show();
        }
    }
    enableForegroundDispatchSystem();
}

一旦我能够读取"有效载荷值，我想指定要运行的代码块.例如:

Once I'm able to "read" the payload value, I want to specify what block of code to run. For example:

protected void onNewIntent(Intent intent) {
    super.onNewIntent(intent);


    ///IF Payload Value = 1...Then run this code block:

    if (intent.hasExtra(NfcAdapter.EXTRA_TAG))
    {
        Toast.makeText(this, "NFC Scan", Toast.LENGTH_SHORT).show();
        Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

        String url = "http://www.google.com";
        Intent i = new Intent(Intent.ACTION_VIEW);
        i.setData(Uri.parse(url));
        startActivity(i);
    }

    ///IF Payload = 2, then run this code block: 

 if (intent.hasExtra(NfcAdapter.EXTRA_TAG))
    {
        Toast.makeText(this, "NFC Scan", Toast.LENGTH_SHORT).show();
        Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

        String url = "http://www.yahoo.com";
        Intent i = new Intent(Intent.ACTION_VIEW);
        i.setData(Uri.parse(url));
        startActivity(i);
    }

}

我希望这是有道理的，我只是试图根据已写入标记的有效负载的值运行一个简单的"if/else"语句.谢谢您的帮助！

I hope this makes sense, I'm only trying to run a simple "if/else" statement based on the value of the Payload that has been written to the tag. Thanks for any help!!

推荐答案

假定您在OnResume中引用了字符串变量payload，则可以编写:

Assuming that you refer to the String variable payload in OnResume, then you can write:

if (payload.equals("1")) {...}

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