小编Mah*_*esh的帖子

我想打开按钮点击的蓝牙设置,如图所示

HomeActivity.java

button.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                final Intent intent = new Intent(Intent.ACTION_MAIN, null);
                intent.addCategory(Intent.CATEGORY_LAUNCHER);
                final ComponentName cn = new ComponentName("com.android.settings", "com.android.settings.bluetoothSettings");
                intent.setComponent(cn);
                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                startActivity( intent);
            }
        });

我想在sdcard或外部SD卡中创建数据库为此我已经尝试了这个代码并使用这个我已经在SD卡中成功创建了数据库,但在logcat中它给了我如下警告

logcat的

07-18 14:18:22.140:W/FileUtils(8595):chmod失败(/ mnt/sdcard/peakmedia/DB_PMD):libcore.io.ErrnoException:chmod failed:EPERM(不允许操作)

DB_Helper.java

public class DB_Helper extends SQLiteOpenHelper
{

    public DB_Helper(Context context) 
    {   
        super(context, Environment.getExternalStorageDirectory().getAbsolutePath() 
                       + File.separator + DB_Constant.DB.FILE_DIR 
                       + File.separator + DB_Constant.DB.DATABASENAME, null, DB_Constant.DB.DB_VERSION);

    }

    @Override
    public void onCreate(SQLiteDatabase db) 
    {
        String  query=String.format(DB_Constant.CREATE_TABLE_QUERY.CREATE_MYFILES_TABLE);
        db.execSQL(query);


        query=String.format(DB_Constant.CREATE_TABLE_QUERY.CREATE_MYUSERS_TABLE);
        db.execSQL(query);

        query=String.format(DB_Constant.CREATE_TABLE_QUERY.CREATE_MYPLAYLIST_TABLE);
        db.execSQL(query);

        query=String.format(DB_Constant.CREATE_TABLE_QUERY.CREATE_MYDEVICE_TABLE);
        db.execSQL(query);

    }

     @Override
     public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) 
     {
            if(newVersion > oldVersion)
            {   

                db.execSQL("DROP TABLE IF EXISTS "+ DB_Constant.TABLE.MYFILES);
                onCreate(db);

                db.execSQL("DROP TABLE IF EXISTS "+ DB_Constant.TABLE.MYUSERS);
                onCreate(db);

                db.execSQL("DROP TABLE IF EXISTS "+ DB_Constant.TABLE.MYPLAYLIST); …

我在动作栏活动中使用导航抽屉现在我在相同的活动中使用了多个片段,但问题是当我第一次加载mapfragment时它显示完美但是当我按下后退我的应用程序崩溃时它显示非法参数异常.

Mapfragment.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.json.JSONObject;

import com.compass.DirectionsJSONParser;
import com.compass.GPSTracker;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapsInitializer;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class MapFragment extends Fragment {

    GoogleMap googlemap;
    GPSTracker gps;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_map,container,false); …

大家好我想问一下,如果我在super.onDestroyView()之前写了什么东西有什么区别; 并在super.onDestroyView()之后; 见下面的例子

在super.ondestoryview()之前删除片段;

@Override
    public void onDestroyView() {

        try {
            Fragment fragment = (getFragmentManager()
                    .findFragmentById(R.id.mapviews));
            FragmentTransaction ft = getActivity().getSupportFragmentManager()
                    .beginTransaction();
            ft.remove(fragment);
            ft.commit();
        } catch (Exception e) {
            e.printStackTrace();
        }
        super.onDestroyView();
    }

在super.ondestoryview()之后删除片段;

@Override
    public void onDestroyView() {
        super.onDestroyView();
        try {
            Fragment fragment = (getFragmentManager()
                    .findFragmentById(R.id.mapviews));
            FragmentTransaction ft = getActivity().getSupportFragmentManager()
                    .beginTransaction();
            ft.remove(fragment);
            ft.commit();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

我打算在android中的应用程序计费中实施托管，我尝试了一个简单的示例应用程序，但是当我在设备上运行该应用程序时，它给了我错误。

我不知道自己在做什么错以及为什么会发生此错误。

首先显示弹出窗口

当我单击“确定”时，它将给我错误日志。

第二个显示弹出窗口

06-23 14:37:04.912: E/Trivial Drive(19340): **** Trivial Drive Error: Error purchasing: IabResult: User canceled. (response: -1005:User cancelled)

当应用程序崩溃我得到这个错误我不明白这个错误说的错误.在这里我把邮件的崩溃日志报告.检查下面我使用下面的方法打开和关闭数据库我已经定义了2954行错误

private void Open_Database() 
    {
        //this is 2954 line 
        mDB_Helper = new DB_Helper(this);
        mSQLiteDatabase = mDB_Helper.getWritableDatabase();

    }

    /* Closing DB */
    private void Close_Database() 
    {

        if (mSQLiteDatabase != null && mDB_Helper != null) 
        {

            mSQLiteDatabase.close();
            mDB_Helper.close();

        }

    }

public void deletedata()
{
     deleteplaylist.clear();

     Open_Database();        
     deleteplaylist=new ArrayList<HashMap<String,String>>();
     deleteplaylist=mDB_Helper.DeleteRecordDetail(mSQLiteDatabase, DB_Constant.TABLE.MYFILES,DB_Constant.MYFILES.USERID, sid);

     Close_Database();


     for(int m=0;m<deleteplaylist.size();m++)
     {
            String getid=deleteplaylist.get(m).get(DB_Constant.MYFILES.FILE_ID).toString();
            String getpath=deleteplaylist.get(m).get(DB_Constant.MYFILES.FILE_PATH).toString();

            Open_Database();

            DB_Helper.DeleteData(mSQLiteDatabase, DB_Constant.TABLE.MYFILES,DB_Constant.MYFILES.USERID, sid,DB_Constant.MYFILES.FILE_ID,getid);
            File file = new File(getpath);
            boolean deleted = file.delete();

            Close_Database();


    }

}

.

2014-11-08-19-56-30
Yoddle

Error Report collected on …

在我的登录和注销功能的应用程序中,我正在检查活动开始时共享首选项是否为空,但我仍然得到NullPointerException.

这是我的HomeActivity.java代码:

// Username And Password Editbox
String eusername;
String epassword;

// Shared Preferences String declaration
String spusername;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);     

    SharedPreferences spreferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
    spusername=spreferences.getString("spusername","");

    if(!spusername.equals(""))
    {   
        Log.e("Spusername not null","-->"+spusername);
    }
    if(spusername==null)
    {
        Log.e("Spusername null","-->"+spusername);
    }
}

我想开始一个被叫的ProgressDialog时候onPreExecute(),但它不起作用.

Homeactivity.java

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    //switch condtion...
    case R.id.buttontime :                
        new FlightListTask().execute("");
        break:  

}

public class FlightListTask extends AsyncTask<String,ArrayList<HashMap<String, String>>, ArrayList<HashMap<String, String>>> {

    protected String onPreExecute(String temp) {
        progresdialoglistview=ProgressDialog.show(HomeActivity.this, "", "Loading");
        Log.e("onPreExecutive","called"+progresdialoglistview);
        return temp;
    }

    @Override
    protected ArrayList<HashMap<String, String>> doInBackground( String... params ) {
        return flightlist;
    }

    protected void onPostExecute(ArrayList<HashMap<String, String>> flightList) {
        // listview code....
    }

}

我正在使用下载管理器同时下载多个文件。但我的问题是下载管理器同时开始下载所有文件我需要在队列中一个一个开始下载文件意味着第一个项目首先下载而不是一个一个。

下载管理器.Java

if(downloaddata.size()>0){              
   for(int i=0;i<downloaddata.size();i++){
        downloadFiles(downloaddata.get(i).getFile_id(),downloaddata.get(i).getFile_url(),"OTHER");
   }
}   


 public void downloadFiles(String myid,String myurl,String type){
        createFolder();
        String fileName = URLUtil.guessFileName(myurl, null, null);
        Uri uri=Uri.parse(myurl);
        request=new DownloadManager.Request(uri);
        request.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI);
        request.setTitle(myid);
        request.setMimeType(type);
        request.setDestinationInExternalPublicDir("/peakmedia",fileName);            request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_HIDDEN);
        downloadReference=downloadManager.enqueue(request);
        downloadlist.add(downloadReference);

    }

当我得到回应时,成功课程完美无缺.但是当它失败时它给了我错误.

在URL中传递失败数据时的响应:

{
  "success": -1,
  "message": "Invalid username or password",
  "data": ""
}

正确数据在URL中传递时的响应:

{
  "success": 1,
  "message": "User successfully logged in",
  "data": {
    "userId": 219,
    "userName": "mp",
    "picture": "219.png",
    "isBo": false,
    "isPo": true,
    "isHm": true,
    "hmProfileCompletionStatus": 3,
    "poProfileCompletionStatus": 2,
    "poPhoto": null,
    "hmPhoto": null,
    "custStripeToken": "xxx",
    "accountStripeToken": "xx",
    "bgcStatus": true,
    "idCardStatus": true,
    "isInsured": null,
    "amISponsered": false,
    "hmRating": null,
    "poRating": null,
    "email": "xxx@gmail.com"
  }
}

UserResponse.java

@Getter
@Setter
public class UserResponse{
    private int success;
    private String message;
    private User data;
} …

我正在尝试使用水平进度条,Asynctask但它不适合我.它不显示进度百分比.

在这里我把我的xml和活动文件和屏幕截图文件.

布局xml

<RelativeLayout
        xmlns:android="http://schemas.android.com/apk/res/android" 
        android:id="@+id/progresslayout"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        >

        <ImageView
            android:id="@+id/imagepeakmedia"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:adjustViewBounds="true"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:src="@drawable/peakmedialogo" 
            android:layout_marginTop="100sp"
             />



        <TextView
            android:id="@+id/text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/imagepeakmedia"
            android:layout_centerHorizontal="true"
            android:textSize="25sp"
           android:text="" />

        <TextView
            android:id="@+id/textpercentage"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/imagepeakmedia"
            android:layout_toRightOf="@+id/text"
            android:layout_centerHorizontal="true"
            android:textSize="25sp"
            android:layout_marginLeft="5sp"
            android:text="%" />

        <ProgressBar
            android:id="@+id/progressBar"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/text"
            style="?android:attr/progressBarStyleHorizontal"

             />

    </RelativeLayout>

TestActivity.java

public class TestActivity extends Activity {


    ProgressDialog progressdialog;

    RelativeLayout progresslayout;
    ProgressBar progressbar;
    TextView textprogressbar;
    TextView textpercentage;
    TextView textdownload;

    boolean progress=true;
    /** Called when the activity is first created. */ …