Android 微调器是空的
我试图用MySQL中的数据填充微调器(我必须填充行),但它们保持为空。此外,这些微调器应该相互依赖。你知道为什么吗?当我在本地主机中调用url时,它返回正确的值,因此PHP工作正常(例如PHP中的一行:[{“Grad”:“Beograd”,“Predmet”:“matematika”}…],我更担心将这些行放入列表中Android 微调器是空的,android,Android,我试图用MySQL中的数据填充微调器(我必须填充行),但它们保持为空。此外,这些微调器应该相互依赖。你知道为什么吗?当我在本地主机中调用url时,它返回正确的值,因此PHP工作正常(例如PHP中的一行:[{“Grad”:“Beograd”,“Predmet”:“matematika”}…],我更担心将这些行放入列表中 public class IzboraGrada extends Activity { Spinner spinner1, spinner2; private Bu
public class IzboraGrada extends Activity {
Spinner spinner1, spinner2;
private Button button,izlaz;
static String str_grad,str_predmet,url;
InputStream is=null;
String result=null;
String line=null;
String[] grad, predmet;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_izbora_grada);
spinner1=(Spinner) findViewById(R.id.spinner1);
spinner2=(Spinner) findViewById(R.id.spinner2);
final List<String> list1=new ArrayList<String>();
final List<String> list2=new ArrayList<String>();
Button b=(Button) findViewById(R.id.button);
b.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
try
{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://192.168.1.14/test/spinner1.php");
HttpResponse response = httpclient.execute(httppost);
Log.e("Fail 1", "3");
HttpEntity entity = response.getEntity();
Log.e("Fail 1", "4");
is = entity.getContent();
Log.e("Pass 1", "connection success ");
}
catch(Exception e)
{
Log.e("Fail 1", e.toString());
Toast.makeText(getApplicationContext(), "Invalid IP Address",Toast.LENGTH_LONG).show();
finish();
}
try
{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
while ((line = reader.readLine()) != null)
{
sb.append(line + "\n");
}
is.close();
result = sb.toString();
}
catch(Exception e)
{
Log.e("Fail 2", e.toString());
}
try
{
JSONArray JA=new JSONArray(result);
JSONObject json= null;
grad = new String[JA.length()];
predmet = new String[JA.length()];
for(int i=0;i<JA.length();i++)
{
json=JA.getJSONObject(i);
grad[i] = json.getString("Grad");
predmet[i]=json.getString("Predmet");
}
Toast.makeText(getApplicationContext(), "sss",Toast.LENGTH_LONG).show();
for(int i=0;i<grad.length;i++)
{
list1.add(grad[i]);
list2.add(predmet[i]);
}
spinner_fn();
}
catch(Exception e)
{
Log.e("Fail 3", e.toString());
//login.this.finish();
}
}
});
}
private void spinner_fn() {
// TODO Auto-generated method stub
ArrayAdapter<String> dataAdapter1 = new ArrayAdapter<String>(getApplicationContext(),
android.R.layout.simple_spinner_item, grad);
dataAdapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner1.setAdapter(dataAdapter1);
ArrayAdapter<String> dataAdapter2 = new ArrayAdapter<String>(getApplicationContext(),
android.R.layout.simple_spinner_item, predmet);
dataAdapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner2.setAdapter(dataAdapter2);
spinner1.setOnItemSelectedListener(new OnItemSelectedListener()
{
public void onItemSelected(AdapterView<?> arg0, View arg1,int position, long id)
{
// TODO Auto-generated method stub
spinner2.setSelection(position);
}
@Override
public void onNothingSelected(AdapterView<?> arg0)
{
// TODO Auto-generated method stub
}
});
spinner2.setOnItemSelectedListener(new OnItemSelectedListener() {
public void onItemSelected(AdapterView<?> arg0, View arg1,int position, long arg3) {
// TODO Auto-generated method stub
spinner1.setSelection(position);
}
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});
}
}
您没有填充微调器,请查看代码的一部分
ArrayAdapter<String> dataAdapter1 = new ArrayAdapter<String>(getApplicationContext(),
dataAdapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
ArrayAdapter dataAdapter1=新的ArrayAdapter(getApplicationContext(),
dataAdapter2.setDropDownViewResource(android.R.layout.simple\u微调器\u下拉菜单\u项);
Android将其作为一行读取,没有对正确数据的有效引用。请将其替换为以下内容:
// adapter for spinner
ArrayAdapter<String> dataAdapter1 = new ArrayAdapter<String>(getApplicationContext(), $$$, list1);
// set layout
dataAdapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
//微调器适配器
ArrayAdapter dataAdapter1=新的ArrayAdapter(getApplicationContext(),$$$,list1);
//集合布局
dataAdapter1.setDropDownViewResource(android.R.layout.simple\u微调器\u下拉菜单\u项);
将$$$替换为XML布局中的微调器项id。对微调器2执行相同操作php是否返回任何内容?当您从uri中读取行时,是否可以在调试模式中看到值?php返回以下内容:[{“Grad”:“Beograd”,“premet”:“matematika”},{“Grad”:“Novi_Sad”,“premet”:“matematika”}、{“Grad”:“Novi_Sad”,“premet”:“matematika”}.]选中此项需要传递ur值,而不是此ans示例代码中传递的字母表…“grad”和“PreMet”列表需要传递…&对于ws-call流程使用异步任务会更困难…出于某种原因,它没有复制该部分代码。我将编辑我的帖子。几分钟后查看。将dataAdapter代码段中的“grad”替换为“list1”并“predmet”改为“list2”,因为最后一个参数应该来自列表类型。我按照您所说的做了,但是list1无法解析为变量。然后您将最终列表list1=new ArrayList()移动;脱离onCreat并将其留在IzboraGrada类中,但没有任何帮助。看起来返回的数据实际上是一个JSON对象,而不是JSON数组;JSON数组嵌套在外部对象中。我发现了一个非常类似的问题,但我不知道如何在我的代码中使用它,以及要更改什么。您能帮助我吗。
// adapter for spinner
ArrayAdapter<String> dataAdapter1 = new ArrayAdapter<String>(getApplicationContext(), $$$, list1);
// set layout
dataAdapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);