記錄一下APP怎么通過以太坊的RPC接口實現遠程調用。此過程的環境為Window7和Android studio2.2.3。以web3_clientVersion為例。更多用法參考Geth JSON-RPC和Management APIs。首先啟動geth私有鏈并設定RPC端口

geth --identity “blossom” --rpc --rpccorsdomain “*” --datadir “%cd%” --port “30303” --rpcapi “personal,db,eth,net,web3,miner” --networkid 66666 --rpcport 8545 console 2>geth.txt

Android studio新建項目并添加.jar包。jar包下載

布局如下：

<Buttonandroid:id="@+id/showView"android:layout_width="match_parent"android:layout_height="wrap_content"android:text="getBlock"/><TextViewandroid:layout_width="match_parent"android:layout_height="match_parent"android:id="@+id/textview"/>

MainActivity如下：

package com.ethereum;

import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.Button;import android.widget.TextView;

import org.alexd.jsonrpc.JSONRPCException;import org.alexd.jsonrpc.JSONRPCHttpClient;

import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

private Button showButton; private TextView textview;public static final int SHOW = 0;private Handler handler = new Handler() {public void handleMessage(Message msg) {switch (msg.what) {case SHOW:String a = (String) msg.obj;textview.setText(a);}} };[@Override](/user/Override) protected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);textview=(TextView)findViewById(R.id.textview);showButton = (Button) findViewById(R.id.showView);showButton.setOnClickListener(this); }[@Override](/user/Override) public void onClick(View v) {if(v.getId() == R.id.showView) {show();} }private void show() {new Thread(new Runnable() {[@Override](/user/Override)public void run() {try {String url = "http://10.0.2.2:8545";JSONRPCHttpClient client = new JSONRPCHttpClient(url);Map<String, Object> map = new HashMap();List paramsList = new ArrayList();map.put("json-rpc", "2.0");map.put("method", "web3_clientVersion");map.put("params", paramsList);map.put("id", "67");String st = client.callString("web3_clientVersion", map);Message msg = new Message();msg.what =SHOW;msg.obj = st;handler.sendMessage(msg);} catch (JSONRPCException e) {e.printStackTrace();}}}).start(); }

}

添加權限：

<uses-permission android:name="android.permission.INTERNET"/>

點擊Button以后結果：

總結

以上是生活随笔為你收集整理的android app通过Geth RPC接口实现远程调用的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。