我想从 Android 应用程序调用智能合约方法。我在我的私有网络中使用 truffle 框架部署了智能合约。我还使用 web3j 命令为部署的智能合约创建了一个包装类。它在我的 Android 项目中创建了一个 .java 文件。
我想从我的 Android 应用程序中调用智能合约方法。这是我的代码:
import android.net.Credentials;
import android.renderscript.Type;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import com.bodaty.deyaPay.Product;
import org.web3j.crypto.CipherException;
import org.web3j.crypto.WalletUtils;
import org.web3j.protocol.Web3j;
import org.web3j.protocol.Web3jFactory;
import org.web3j.protocol.core.RemoteCall;
import org.web3j.protocol.core.methods.response.TransactionReceipt;
import org.web3j.protocol.http.HttpService;
import org.web3j.tx.Contract;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {
TextView t;
EditText e;
Button b1,b2;
Web3j web3 = Web3jFactory.build(new HttpService());
org.web3j.crypto.Credentials credentials = WalletUtils.loadCredentials(" ","/usr/local/Cellar/test3/keystore/UTC--2018-03-13T09-19-38.721370320Z--191a1be7c53236f916af5512329a5092f70fab59 ");
Product p = Product.load("0x3ed0585f956acc406dc0f5e97524b6a2d30bce57",web3,credentials, Contract.GAS_LIMIT,Contract.GAS_PRICE);
public MainActivity() throws IOException, CipherException {
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
t = (TextView) findViewById(R.id.textView);
e = (EditText) findViewById(R.id.editText);
b1 = (Button) findViewById(R.id.button);
b2 = (Button) findViewById(R.id.button2);
b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String a = e.getText().toString();
//Product p = Product.load("0x3ed0585f956acc406dc0f5e97524b6a2d30bce57",web3,credentials, Contract.GAS_LIMIT,Contract.GAS_PRICE);
try {
TransactionReceipt result = p.set(a).send();
} catch (Exception e1) {
e1.printStackTrace();
}
}
});
b2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String a = e.getText().toString();
try {
RemoteCall<String> result = p.get(a);
} catch (Exception e1) {
e1.printStackTrace();
}
}
});
}
}
我收到错误:
java.io.FileNotFoundException: /usr/local/Cellar/test3/keystore/UTC--2018-03-13T09-19-38.721370320Z--191a1be7c53236f916af5512329a5092f70fab59 : open failed: ENOENT (No such file or directory)
如何提供钱包地址以及如何将这些方法调用到我的 Android 应用程序中?