0
このコードを正常に動作させるには問題があります。JavaでのアンドロイドのListActivities間でのデータの受け渡し
基本的には、1つのリストアクティビティから別のリストアクティビティに移動し、アクティビティのインテントを通してテキストを新しいリストビューに渡し、新しいリストアクティビティでそのテキストを取得してから、そのリスト項目の値。
ログイン猫
04-05 17:47:32.370: E/AndroidRuntime(30135): FATAL EXCEPTION: main
04-05 17:47:32.370: E/AndroidRuntime(30135): java.lang.ClassCastException:android.widget.LinearLayout
04-05 17:47:32.370: E/AndroidRuntime(30135): at com.thickcrustdesigns.ufood.CatogPage$1.onItemClick(CatogPage.java:66)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.widget.AdapterView.performItemClick(AdapterView.java:284)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.widget.ListView.performItemClick(ListView.java:3731)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.widget.AbsListView$PerformClick.run(AbsListView.java:1959)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.os.Handler.handleCallback(Handler.java:587)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.os.Handler.dispatchMessage(Handler.java:92)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.os.Looper.loop(Looper.java:130)
04-05 17:47:32.370: E/AndroidRuntime(30135): at android.app.ActivityThread.main(ActivityThread.java:3691)
04-05 17:47:32.370: E/AndroidRuntime(30135): at java.lang.reflect.Method.invokeNative(Native Method)
04-05 17:47:32.370: E/AndroidRuntime(30135): at java.lang.reflect.Method.invoke(Method.java:507)
04-05 17:47:32.370: E/AndroidRuntime(30135): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
04-05 17:47:32.370: E/AndroidRuntime(30135): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:665)
04-05 17:47:32.370: E/AndroidRuntime(30135): at dalvik.system.NativeStart.main(Native Method)
ListActivity 1
package com.thickcrustdesigns.ufood;
import java.util.ArrayList;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
public class CatogPage extends ListActivity {
ListView listView1;
Button btn_bk;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.definition_main);
btn_bk = (Button) findViewById(R.id.btn_bk);
listView1 = (ListView) findViewById(android.R.id.list);
ArrayList<NameValuePair> nvp = new ArrayList<NameValuePair>();
nvp.add(new BasicNameValuePair("request", "categories"));
ArrayList<JSONObject> jsondefs = Request.fetchData(this, nvp);
String[] defs = new String[jsondefs.size()];
for (int i = 0; i < jsondefs.size(); i++) {
try {
defs[i] = jsondefs.get(i).getString("Name");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
uFoodAdapter adapter = new uFoodAdapter(this, R.layout.definition_list,
defs);
listView1.setAdapter(adapter);
ListView lv = getListView();
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
TextView tv = (TextView) view;
String p = tv.getText().toString();
Intent i = new Intent(getApplicationContext(), Results.class);
i.putExtra("category", p);
startActivity(i);
}
});
btn_bk.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
Intent i = new Intent(getApplicationContext(),
UFoodAppActivity.class);
startActivity(i);
}
});
}
}
**ListActivity 2**
package com.thickcrustdesigns.ufood;
import java.util.ArrayList;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.os.Bundle;
import android.widget.ListView;
public class Results extends ListActivity {
ListView listView1;
enum Category {
Chicken, Beef, Chinese, Cocktails, Curry, Deserts, Fish, ForOne {
public String toString() {
return "For One";
}
},
Lamb, LightBites {
public String toString() {
return "Light Bites";
}
},
Pasta, Pork, Vegetarian
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.setContentView(R.layout.definition_main);
listView1 = (ListView) findViewById(android.R.id.list);
Bundle data = getIntent().getExtras();
String category = data.getString("category");
Category cat = Category.valueOf(category);
String value = null;
switch (cat) {
case Chicken:
value = "Chicken";
break;
case Beef:
value = "Beef";
break;
case Chinese:
value = "Chinese";
break;
case Cocktails:
value = "Cocktails";
break;
case Curry:
value = "Curry";
break;
case Deserts:
value = "Deserts";
break;
case Fish:
value = "Fish";
break;
case ForOne:
value = "ForOne";
break;
case Lamb:
value = "Lamb";
break;
case LightBites:
value = "LightBites";
break;
case Pasta:
value = "Pasta";
break;
case Pork:
value = "Pork";
break;
case Vegetarian:
value = "Vegetarian";
}
ArrayList<NameValuePair> nvp = new ArrayList<NameValuePair>();
nvp.add(new BasicNameValuePair("request", "category"));
nvp.add(new BasicNameValuePair("cat", value));
ArrayList<JSONObject> jsondefs = Request.fetchData(this, nvp);
String[] defs = new String[jsondefs.size()];
for (int i = 0; i < jsondefs.size(); i++) {
try {
defs[i] = jsondefs.get(i).getString("Name");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
uFoodAdapter adapter = new uFoodAdapter(this, R.layout.definition_list,
defs);
listView1.setAdapter(adapter);
}
}
要求
package com.thickcrustdesigns.ufood;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONObject;
import android.content.Context;
import android.util.Log;
import android.widget.Toast;
public class Request {
@SuppressWarnings("null")
public static ArrayList<JSONObject> fetchData(Context context,
ArrayList<NameValuePair> nvp) {
ArrayList<JSONObject> listItems = new ArrayList<JSONObject>();
InputStream is = null;
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(
"http://co350-11d.projects02.glos.ac.uk/php/database.php");
httppost.setEntity(new UrlEncodedFormEntity(nvp));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
} catch (Exception e) {
Log.e("log_tag", "Error in http connection" + e.toString());
}
// convert response to string
String result = "";
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
InputStream stream = null;
StringBuilder sb = null;
while ((result = reader.readLine()) != null) {
sb.append(result + "\n");
}
stream.close();
result = sb.toString();
} catch (Exception e) {
Log.e("log_tag", "Error converting result " + e.toString());
}
try {
JSONArray jArray = new JSONArray(result);
for (int i = 0; i < jArray.length(); i++) {
JSONObject jo = jArray.getJSONObject(i);
listItems.add(jo);
}
} catch (Exception e) {
Toast.makeText(context.getApplicationContext(), "None Found!",
Toast.LENGTH_LONG).show();
}
return listItems;
}
}
package com.thickcrustdesigns.ufood;
import java.util.ArrayList;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.os.Bundle;
import android.widget.ListView;
public class Results extends ListActivity {
ListView listView1;
enum Category {
Chicken, Beef, Chinese, Cocktails, Curry, Deserts, Fish, ForOne {
public String toString() {
return "For One";
}
},
Lamb, LightBites {
public String toString() {
return "Light Bites";
}
},
Pasta, Pork, Vegetarian
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.setContentView(R.layout.definition_main);
listView1 = (ListView) findViewById(android.R.id.list);
Bundle data = getIntent().getExtras();
String category = data.getString("category");
Category cat = Category.valueOf(category);
String value = null;
switch (cat) {
case Chicken:
value = "Chicken";
break;
case Beef:
value = "Beef";
break;
case Chinese:
value = "Chinese";
break;
case Cocktails:
value = "Cocktails";
break;
case Curry:
value = "Curry";
break;
case Deserts:
value = "Deserts";
break;
case Fish:
value = "Fish";
break;
case ForOne:
value = "ForOne";
break;
case Lamb:
value = "Lamb";
break;
case LightBites:
value = "LightBites";
break;
case Pasta:
value = "Pasta";
break;
case Pork:
value = "Pork";
break;
case Vegetarian:
value = "Vegetarian";
}
ArrayList<NameValuePair> nvp = new ArrayList<NameValuePair>();
nvp.add(new BasicNameValuePair("request", "category"));
nvp.add(new BasicNameValuePair("cat", value));
ArrayList<JSONObject> jsondefs = Request.fetchData(this, nvp);
String[] defs = new String[jsondefs.size()];
for (int i = 0; i < jsondefs.size(); i++) {
try {
defs[i] = jsondefs.get(i).getString("Name");
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
uFoodAdapter adapter = new uFoodAdapter(this, R.layout.definition_list,
defs);
listView1.setAdapter(adapter);
}
}
'（（TextView）ビュー）.getText（）。toString（）;'として実行すると疲れている例もありますが、それはうまくいきませんでした。 –
クイック返信のための乾杯！私はこのプロジェクトのために非常に短い時間スケールを持っています！そのUniプロジェクトは、私がアプリを開発するように言われている！私はマルチメディアの学生ですので、すでに深遠な水に投げ込まれているアプリを作成するタスクを与えられます！私がこれを解決したら、そこからはっきりと実行する必要があります！うまくいけば...... –
明示的キャスティングは、あるクラスのオブジェクトを他のクラスBにキャストしようとしている場合に便利です。 – jeet