我已经连接了android（客户端）和PHP(server)以便检索数据，并且当我单独执行时它成功但是通过提供按钮来连接我的主程序时，不检索数据。通过单击按钮它正在进行加载，然后模块页面将再次出现。
package com.example.sim;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void click(View v){
Intent intent=new Intent(this,AainActivity.class);
startActivity(intent);
}
}
Aainactivity看起来像这样
public class SampleHttp extends AsyncTask<String, String, String> {
private ProgressDialog pDialog;
@Override
protected void onPreExecute() {
pDialog = new ProgressDialog(AainActivity.this);
pDialog.setMessage("Loading . Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
super.onPreExecute();
}
@Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
String result = null;
InputStream is = null;
try {
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://smart.prometheantechnologysolutions.com/s.php");
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
Log.e("log_tag", "connection success");
// Toast.makeText(getApplicationContext(), “pass”,
// Toast.LENGTH_SHORT).show();
} catch (Exception e) {
}
// convert response to string
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(is), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result" + e.toString());
//Toast.makeText(getApplicationContext(), "Input reading fail", Toast.LENGTH_SHORT).show();
}
return result;
}
@Override
protected void onPostExecute(String result) {
try {
JSONArray jArray = new JSONArray(result);
TableLayout tv = (TableLayout) findViewById(R.id.table);
tv.removeAllViewsInLayout();
int flag = 1;
for (int i = -1; i < jArray.length(); i++) {
TableRow tr = new TableRow(AainActivity.this);
tr.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
if (flag == 1) {
TextView b6 = new TextView(AainActivity.this);
b6.setText("Id");
b6.setTextColor(Color.BLUE);
b6.setTextSize(15);
tr.addView(b6);
TextView b19 = new TextView(AainActivity.this);
b19.setPadding(10, 0, 0, 0);
b19.setTextSize(15);
b19.setText("Name");
b19.setTextColor(Color.BLUE);
tr.addView(b19);
TextView b29 = new TextView(AainActivity.this);
b29.setPadding(10, 0, 0, 0);
b29.setText("Address");
b29.setTextColor(Color.BLUE);
b29.setTextSize(15);
tr.addView(b29);
tv.addView(tr);
final View vline = new View(AainActivity.this);
vline.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.FILL_PARENT, 2));
vline.setBackgroundColor(Color.BLUE);
tv.addView(vline);
flag = 0;
} else {
JSONObject json_data = jArray.getJSONObject(i);
Log.i("log_tag", "id: " + json_data.getInt("id") + ", Username: "
+ json_data.getString("name") + ", No: " + json_data.getString("address"));
TextView b = new TextView(AainActivity.this);
String stime = String.valueOf(json_data.getInt("id"));
b.setText(stime);
b.setTextColor(Color.RED);
b.setTextSize(15);
tr.addView(b);
TextView b1 = new TextView(AainActivity.this);
b1.setPadding(10, 0, 0, 0);
b1.setTextSize(15);
String stime1 = json_data.getString("name");
b1.setText(stime1);
b1.setTextColor(Color.BLACK);
tr.addView(b1);
TextView b2 = new TextView(AainActivity.this);
b2.setPadding(10, 0, 0, 0);
String stime2 = json_data.getString("address");
b2.setText(stime2);
b2.setTextColor(Color.BLACK);
b2.setTextSize(15);
tr.addView(b2);
tv.addView(tr);
final View vline1 = new View(AainActivity.this);
vline1.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.FILL_PARENT, 1));
vline1.setBackgroundColor(Color.WHITE);
tv.addView(vline1);
}
}
} catch (Exception e) {
Log.e("log_tag", "Error parsing data" + e.toString());
Toast.makeText(getApplicationContext(), "JsonArray fail", Toast.LENGTH_SHORT).show();
}
pDialog.dismiss();
super.onPostExecute(result);
}
}
我做错了什么？我想通过按钮从数据库中检索数据。
答案 0 :(得分：0)
首先确保您的休息请求正确无误。 I：E;您的服务器正在回复移动设备
如果休息请求成功。 假设您正在从服务器向机器人发送json响应。 验证您的json字符串响应here
它生成java类，将它们复制到项目中，并将gson库添加到gradle中。
你完成了。
Gson gson = new Gson();
gson.fromJson(jsonStr,YourClass.class);
它提供了您正在寻找的所有字段
如果您遇到任何问题，请在下方发表评论。