Java 从数据库搜索后显示空白屏幕（Android）
当我点击search Provider时，它会在listview中显示空白屏幕，我不知道为什么这是我从服务器返回的响应 这是我的自定义适配器代码：Java 从数据库搜索后显示空白屏幕（Android）,java,php,android,json,Java,Php,Android,Json,当我点击search Provider时，它会在listview中显示空白屏幕，我不知道为什么这是我从服务器返回的响应 这是我的自定义适配器代码： package com.example.kamran.ebloodbank; import android.app.Activity; import android.content.Context; import android.support.annotation.NonNull; import android.support.annotatio
package com.example.kamran.ebloodbank;
import android.app.Activity;
import android.content.Context;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.TextView;
import java.util.List;
/**
* Created by Kamran on 4/12/2017.
*/
public class DonorAdapter extends BaseAdapter {
private Activity activity;
private LayoutInflater inflater;
private List<DataSet> donorItems;
public DonorAdapter(Activity activity,List<DataSet> donorItems) {
this.activity = activity;
this.donorItems = donorItems;
}
@Override
public int getCount() {
return donorItems.size();
}
@Override
public Object getItem(int location) {
return donorItems.get(location);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (inflater == null)
inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if (convertView == null)
convertView = inflater.inflate(R.layout.donor_search_list_theme, null);
TextView nameTextView = (TextView) convertView.findViewById(R.id.donor_name);
TextView areaTextView = (TextView) convertView.findViewById(R.id.donor_area);
DataSet d = donorItems.get(position);
nameTextView.setText(d.getName());
areaTextView.setText(d.getArea());
return convertView;
}
}
package com.example.kamran.ebloodbank;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Spinner;
import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import com.example.kamran.ebloodbank.data.BloodContract.BloodEntry;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class FindDonor extends AppCompatActivity {
Spinner bloodgroup;
Spinner area;
String findDonorUrl = "https://wwwkamranalitk.000webhostapp.com/findDonor.php";
int mBlood = BloodEntry.BLOOD_GROUP_A_POS;
int mArea = BloodEntry.DONOR_AREA_MALIR;
Button searchButton;
RequestQueue requestQueue;
StringRequest request;
JSONObject jsonObject;
JSONArray result;
private List<DataSet> donorList = new ArrayList<DataSet>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_find_donor);
bloodgroup = (Spinner) findViewById(R.id.bloodspinnerfinddonor);
area = (Spinner) findViewById(R.id.areaSpinner);
searchButton = (Button) findViewById(R.id.searchDonor);
setupSpinnerBlood();
setupSpinnerArea();
requestQueue = Volley.newRequestQueue(getApplicationContext());
searchButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
request = new StringRequest(Request.Method.POST, findDonorUrl, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
jsonObject = new JSONObject(response);
result = jsonObject.getJSONArray("result");
JSONObject donorData = result.getJSONObject(0);
DataSet donorSet = new DataSet();
donorSet.setName(donorData.getString("name"));
donorSet.setArea(donorData.getInt("area"));
donorList.add(donorSet);
Intent intent = new Intent(FindDonor.this, DonorSearchList.class);
startActivity(intent);
finish();
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
}
}){
@Override
protected Map<String, String> getParams() throws AuthFailureError {
HashMap<String,String> parameters = new HashMap<String, String>();
parameters.put("bloodgroup", String.valueOf(mBlood));
parameters.put("area", String.valueOf(mArea));
return parameters;
}
};
requestQueue.add(request);
}
});
}
private void setupSpinnerBlood() {
ArrayAdapter bloodGroupSpinnerAdapter = ArrayAdapter.createFromResource(this, R.array.blood_group, android.R.layout.simple_spinner_item);
bloodGroupSpinnerAdapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
bloodgroup.setAdapter(bloodGroupSpinnerAdapter);
bloodgroup.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selection = (String) parent.getItemAtPosition(position);
if (!TextUtils.isEmpty(selection)) {
if (selection.equals(getString(R.string.blood_apos))) {
mBlood = BloodEntry.BLOOD_GROUP_A_POS;
} else if (selection.equals((getString(R.string.blood_bpos)))) {
mBlood = BloodEntry.BLOOD_GROUP_B_POS;
} else if (selection.equals(getString(R.string.blood_opos))) {
mBlood = BloodEntry.BLOOD_GROUP_O_POS;
} else if (selection.equals((getString(R.string.blood_oneg)))) {
mBlood = BloodEntry.BLOOD_GROUP_O_NEG;
}
}
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
mBlood = BloodEntry.BLOOD_GROUP_A_POS;
}
});
}
private void setupSpinnerArea() {
ArrayAdapter areaSpinnerAdapter = ArrayAdapter.createFromResource(this, R.array.area, android.R.layout.simple_spinner_item);
areaSpinnerAdapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
area.setAdapter(areaSpinnerAdapter);
area.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selection = (String) parent.getItemAtPosition(position);
if (!TextUtils.isEmpty(selection)) {
if (selection.equals(getString(R.string.donor_area_malir))) {
mArea = BloodEntry.DONOR_AREA_MALIR;
} else if (selection.equals(getString(R.string.donor_area_defence))) {
mArea = BloodEntry.DONOR_AREA_DEFENCE;
} else if (selection.equals(getString(R.string.donor_area_korangi))) {
mArea = BloodEntry.DONOR_AREA_KORANGI;
} else if (selection.equals(getString(R.string.donor_area_johar))) {
mArea = BloodEntry.DONOR_AREA_JOHAR;
}
}
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
mArea = BloodEntry.DONOR_AREA_MALIR;
}
});
}
}
package com.example.kamran.ebloodbank；
导入android.content.Intent；
导入android.support.v7.app.AppActivity；
导入android.os.Bundle；
导入android.text.TextUtils；
导入android.view.view；
导入android.widget.AdapterView；
导入android.widget.ArrayAdapter；
导入android.widget.Button；
导入android.widget.ListView；
导入android.widget.Spinner；
导入com.android.volley.AuthFailureError；
导入com.android.volley.Request；
导入com.android.volley.RequestQueue；
导入com.android.volley.Response；
导入com.android.volley.VolleyError；
导入com.android.volley.toolbox.StringRequest；
导入com.android.volley.toolbox.volley；
导入com.example.kamran.ebloodbank.data.BloodContract.BloodEntry；
导入org.json.JSONArray；
导入org.json.JSONException；
导入org.json.JSONObject；
导入java.util.ArrayList；
导入java.util.HashMap；
导入java.util.List；
导入java.util.Map；
公共类FindDonor扩展了AppCompatActivity{
Spinner血型；
纺纱区；
字符串findDonorUrl=”https://wwwkamranalitk.000webhostapp.com/findDonor.php";
int mBlood=BloodEntry.BLOOD\u GROUP\u A\u POS；
int mArea=血液输入。捐赠者面积；
按钮搜索按钮；
请求队列请求队列；
请求请求；
JSONObject JSONObject；
JSONArray结果；
private List donorList=new ArrayList（）；
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity\u find\u provider）；
血型=（Spinner）findViewById（R.id.BloodPinnerFindProvider）；
面积=（微调器）findViewById（R.id.areaSpinner）；
searchButton=（按钮）findViewById（R.id.SearchProvider）；
设置喷丝板血（）；
setupSpinnerArea（）；
requestQueue=Volley.newRequestQueue（getApplicationContext（））；
searchButton.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图）{
request=new-StringRequest（request.Method.POST、findDonorUrl、new-Response.Listener（）{
@凌驾
公共void onResponse（字符串响应）{
试一试{
jsonObject=新的jsonObject（响应）；
result=jsonObject.getJSONArray（“结果”）；
JSONObject donorData=result.getJSONObject（0）；
数据集提供者集=新数据集（）；
donorSet.setName（donorData.getString（“name”）；
donorSet.setArea（donorData.getInt（“区域”））；
donorList.add（donorSet）；
意向意向=新意向（FindDonor.this，DonorSearchList.class）；
星触觉（意向）；
完成（）；
}捕获（JSONException e）{
e、 printStackTrace（）；
}
}
}，new Response.ErrorListener（）{
@凌驾
公共无效onErrorResponse（截击错误）{
}
}){
@凌驾
受保护的映射getParams（）引发AuthFailureError{
HashMap参数=新的HashMap（）；
parameters.put（“bloodgroup”，String.valueOf（mBlood））；
parameters.put（“area”，String.valueOf（mArea））；
返回参数；
}
};
添加（请求）；
}
});
}
私人喷浆器血液（）{
ArrayAdapter-bloodGroupSpinnerAdapter=ArrayAdapter.createFromResource（这个，R.array.blood\u组，android.R.layout.simple\u微调器\u项）；
bloodGroupSpinnerAdapter.setDropDownViewResource（android.R.layout.simple\u dropdown\u item\u 1line）；
bloodgroup.setAdapter（bloodGroupSpinnerAdapter）；
bloodgroup.setOnItemSelectedListener（新的AdapterView.OnItemSelectedListener（）{
@凌驾
已选择公共视图（AdapterView父视图、视图视图、整型位置、长id）{
字符串选择=（字符串）parent.getItemAtPosition（位置）；
如果（！TextUtils.isEmpty（选择））{
if（selection.equals（getString（R.string.blood_apos）））{
mBlood=BloodEntry.BLOOD\u GROUP\u POS；
}else if（selection.equals（（getString（R.string.blood_bpos）））{
mBlood=BloodEntry.BLOOD\u GROUP\u B\u POS；
}else if（selection.equals（getString（R.string.blood_opos）））{
mBlood=BloodEntry.BLOOD\u GROUP\u O\u POS；
}else if（selection.equals（（getString（R.string.blood_oneg）））{
mBlood=BloodEntry.BLOOD\u GROUP\u O\u NEG；
}
}
}
@凌驾
未选择公共无效（AdapterView AdapterView）{
mBlood=BloodEntry.BLOOD\u GROUP\u POS；
}
});
}
私有虚拟空间设置SpinneRarea（）{
ArrayAdapter areaSpinnerAdapter=ArrayAdapter.createFromResource（这个，R.array.area，android.R.layout.simple\u微调器\u项）；
areaSpinnerAdapter.setDropDownViewResource（android.R.layout.simple_dropdown_项目线）；
area.setAdapter（areaSpinnerAdapter）；
area.setOnItemSelectedListener（新的AdapterView.OnItemSelectedListener（）{
@凌驾
已选择公共视图（AdapterView父视图、视图、int posi
package com.example.kamran.ebloodbank;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Spinner;
import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import com.example.kamran.ebloodbank.data.BloodContract.BloodEntry;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class FindDonor extends AppCompatActivity {
Spinner bloodgroup;
Spinner area;
String findDonorUrl = "https://wwwkamranalitk.000webhostapp.com/findDonor.php";
int mBlood = BloodEntry.BLOOD_GROUP_A_POS;
int mArea = BloodEntry.DONOR_AREA_MALIR;
Button searchButton;
RequestQueue requestQueue;
StringRequest request;
JSONObject jsonObject;
JSONArray result;
private List<DataSet> donorList = new ArrayList<DataSet>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_find_donor);
bloodgroup = (Spinner) findViewById(R.id.bloodspinnerfinddonor);
area = (Spinner) findViewById(R.id.areaSpinner);
searchButton = (Button) findViewById(R.id.searchDonor);
setupSpinnerBlood();
setupSpinnerArea();
requestQueue = Volley.newRequestQueue(getApplicationContext());
searchButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
request = new StringRequest(Request.Method.POST, findDonorUrl, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
jsonObject = new JSONObject(response);
result = jsonObject.getJSONArray("result");
JSONObject donorData = result.getJSONObject(0);
DataSet donorSet = new DataSet();
donorSet.setName(donorData.getString("name"));
donorSet.setArea(donorData.getInt("area"));
donorList.add(donorSet);
Intent intent = new Intent(FindDonor.this, DonorSearchList.class);
startActivity(intent);
finish();
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
}
}){
@Override
protected Map<String, String> getParams() throws AuthFailureError {
HashMap<String,String> parameters = new HashMap<String, String>();
parameters.put("bloodgroup", String.valueOf(mBlood));
parameters.put("area", String.valueOf(mArea));
return parameters;
}
};
requestQueue.add(request);
}
});
}
private void setupSpinnerBlood() {
ArrayAdapter bloodGroupSpinnerAdapter = ArrayAdapter.createFromResource(this, R.array.blood_group, android.R.layout.simple_spinner_item);
bloodGroupSpinnerAdapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
bloodgroup.setAdapter(bloodGroupSpinnerAdapter);
bloodgroup.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selection = (String) parent.getItemAtPosition(position);
if (!TextUtils.isEmpty(selection)) {
if (selection.equals(getString(R.string.blood_apos))) {
mBlood = BloodEntry.BLOOD_GROUP_A_POS;
} else if (selection.equals((getString(R.string.blood_bpos)))) {
mBlood = BloodEntry.BLOOD_GROUP_B_POS;
} else if (selection.equals(getString(R.string.blood_opos))) {
mBlood = BloodEntry.BLOOD_GROUP_O_POS;
} else if (selection.equals((getString(R.string.blood_oneg)))) {
mBlood = BloodEntry.BLOOD_GROUP_O_NEG;
}
}
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
mBlood = BloodEntry.BLOOD_GROUP_A_POS;
}
});
}
private void setupSpinnerArea() {
ArrayAdapter areaSpinnerAdapter = ArrayAdapter.createFromResource(this, R.array.area, android.R.layout.simple_spinner_item);
areaSpinnerAdapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
area.setAdapter(areaSpinnerAdapter);
area.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selection = (String) parent.getItemAtPosition(position);
if (!TextUtils.isEmpty(selection)) {
if (selection.equals(getString(R.string.donor_area_malir))) {
mArea = BloodEntry.DONOR_AREA_MALIR;
} else if (selection.equals(getString(R.string.donor_area_defence))) {
mArea = BloodEntry.DONOR_AREA_DEFENCE;
} else if (selection.equals(getString(R.string.donor_area_korangi))) {
mArea = BloodEntry.DONOR_AREA_KORANGI;
} else if (selection.equals(getString(R.string.donor_area_johar))) {
mArea = BloodEntry.DONOR_AREA_JOHAR;
}
}
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
mArea = BloodEntry.DONOR_AREA_MALIR;
}
});
}
}
package com.example.kamran.ebloodbank;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ListView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class DonorSearchList extends AppCompatActivity {
private String mArea;
private List<DataSet> donorList = new ArrayList<DataSet>();
private ListView listView;
private DonorAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_donor_search_list);
listView = (ListView) findViewById(R.id.donorListView);
adapter = new DonorAdapter(this, donorList);
listView.setAdapter(adapter);
}
}
public class bridge {
public static List<DataSet> donorList = new ArrayList<DataSet>();
}
donorSet.setName(donorData.getString("name"));
donorSet.setArea(donorData.getInt("area"));
donorList.add(donorSet);
//here put this line
bridge.donarList = donarList;
//rest code
Intent intent = new Intent(FindDonor.this, DonorSearchList.class);
adapter = new DonorAdapter(this, bridge.donorList);