Question

我是Android开发的新手，我正在尝试将数据插入到Android中的SQLite数据库中。我有一个问题找到解决方案，在哪里可以看到代码，如何将图像和文本插入数据库。你知道一些文章/书籍吗？他们帮助我的其他东西？

我编写了一些只插入文本的代码，但我无法将它们一起插入。插入后，我想要详细检索文本和图像活动。

非常感谢你的帮助。

我可以上传代码。

我的DatabaseHelper：

 public class DatabaseHelpher extends SQLiteOpenHelper {
    private static final String DATABASE_NAME="student";
    private static final int DATABASE_VERSION = 1;
    private static final String STUDENT_TABLE = "stureg";
    private static final String STU_TABLE = "create table "+STUDENT_TABLE +"(name TEXT,email TEXT primary key,roll TEXT,address TEXT,branch TEXT)";

    Context context;

    public DatabaseHelpher(final Context context) {
        super(context, Environment.getExternalStorageDirectory()
                + File.separator + DATABASE_NAME, null, DATABASE_VERSION);
        this.context = context;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        db.execSQL(STU_TABLE);
    }

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

        db.execSQL("DROP TABLE IF EXISTS " + STUDENT_TABLE);

        // Create tables again
        onCreate(db);
    }

    public void insertIntoDB(String name,String email,String roll,String address,String branch){
        Log.d("insert", "before insert");

        // 1. get reference to writable DB
        SQLiteDatabase db = this.getWritableDatabase();

        // 2. create ContentValues to add key "column"/value
        ContentValues values = new ContentValues();
        values.put("name", name);
        values.put("email", email);
        values.put("roll", roll);
         values.put("address", address);
        values.put("branch", branch);

        // 3. insert
        db.insert(STUDENT_TABLE, null, values);
        // 4. close
        db.close();
        Toast.makeText(context, "insert value", Toast.LENGTH_LONG);
        Log.i("insert into DB", "After insert");



    }

    public List<DatabaseModel> getDataFromDB(){
        List<DatabaseModel> modelList = new ArrayList<DatabaseModel>();
        String query = "select * from "+STUDENT_TABLE;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(query,null);
        if (cursor.moveToFirst()){
            do {
                DatabaseModel model = new DatabaseModel();
                model.setName(cursor.getString(0));
                model.setEmail(cursor.getString(1));
                model.setRoll(cursor.getString(2));
                model.setAddress(cursor.getString(3));
                model.setBranch(cursor.getString(4));

                modelList.add(model);
            }while (cursor.moveToNext());
        }


        Log.d("student data", modelList.toString());


        return modelList;
    }



    public void deleteARow(String email){
        SQLiteDatabase db= this.getWritableDatabase();
        db.delete(STUDENT_TABLE, "email" + " = ?", new String[] { email });
        db.close();
    }

DatabaseModel：

public class DatabaseModel {
private String name;
private String roll;
private String address;
private String branch;
private String email;
private String image;

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getRoll() {
    return roll;
}

public void setRoll(String roll) {
    this.roll = roll;
}

public String getAddress() {
    return address;
}

public void setAddress(String address) {
    this.address = address;
}

public String getBranch() {
    return branch;
}

public void setBranch(String branch) {
    this.branch = branch;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

public String getImage() {
    return image;
}

public void setImage (String image) {
    this.image = image;
}

DetailsActivity：

 public class DetailsActivity extends AppCompatActivity {
    DatabaseHelpher helpher;
    List<DatabaseModel> dbList;
    int position;
    TextView tvname,tvemail,tvroll,tvaddress,tvbranch;

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

        setContentView(R.layout.activity_details);

        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);


        Intent intent = getIntent();
        Bundle bundle = intent.getExtras();

        // 5. get status value from bundle
         position = bundle.getInt("position");

        tvname =(TextView)findViewById(R.id.name);
        tvemail =(TextView)findViewById(R.id.email);
        tvroll =(TextView)findViewById(R.id.roll);
        tvaddress =(TextView)findViewById(R.id.address);
        tvbranch =(TextView)findViewById(R.id.branch);
        helpher = new DatabaseHelpher(this);
        dbList= new ArrayList<DatabaseModel>();
        dbList = helpher.getDataFromDB();

        if(dbList.size()>0){
            String name= dbList.get(position).getName();
            String email=dbList.get(position).getEmail();
            String roll=dbList.get(position).getRoll();
            String address=dbList.get(position).getAddress();
            String branch=dbList.get(position).getBranch();
            tvname.setText(name);
            tvemail.setText(email);
            tvroll.setText(roll);
            tvaddress.setText(address);
            tvbranch.setText(branch);
        }

        Toast.makeText(DetailsActivity.this, dbList.toString(), Toast.LENGTH_LONG);
    }


    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_details, menu);
        return true;
    }



    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                finish();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

MainActivity：

public class MainActivity extends AppCompatActivity {
EditText etName,etRoll,etAddress,etBranch,etEmail;
Button btnSubmit,btngetdata,btndroptable;
DatabaseHelpher helpher;
List<DatabaseModel> dbList;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    dbList= new ArrayList<DatabaseModel>();
    etName = (EditText)findViewById(R.id.etName);
    etRoll = (EditText)findViewById(R.id.etRoll);
    etAddress =(EditText)findViewById(R.id.etAddress);
    etBranch = (EditText)findViewById(R.id.etBranch);
    etEmail = (EditText)findViewById(R.id.etEmail);
    btnSubmit  =(Button)findViewById(R.id.btnSubmit);
    btngetdata =(Button)findViewById(R.id.btngetdata);

    btngetdata.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            startActivity(new Intent(MainActivity.this, SecondActivity.class));

           // startActivity(new Intent(MainActivity.this, DetailsActivity.class));

        }
    });

    btnSubmit.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            String name=etName.getText().toString();
            String email=etEmail.getText().toString();
            String roll=etRoll.getText().toString();
            String address=etAddress.getText().toString();
            String branch=etBranch.getText().toString();

        if(name.equals("") || email.equals("") || roll.equals("") ||address.equals("")||branch.equals("")){
            Toast.makeText(MainActivity.this,"Please fill all the fields",Toast.LENGTH_LONG).show();
        }else {
            helpher = new DatabaseHelpher(MainActivity.this);
            helpher.insertIntoDB(name, email, roll, address, branch);
        }
            etName.setText("");
            etRoll.setText("");
            etAddress.setText("");
            etBranch.setText("");
            etEmail.setText("");

            Toast.makeText(MainActivity.this, "insert value", Toast.LENGTH_LONG);

        }
    });

RecyclerAdapter：

 public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.ViewHolder> {

    static   List<DatabaseModel> dbList;
        static  Context context;
        RecyclerAdapter(Context context, List<DatabaseModel> dbList ){
            this.dbList = new ArrayList<DatabaseModel>();
            this.context = context;
            this.dbList = dbList;

        }
    @Override
    public RecyclerAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View itemLayoutView = LayoutInflater.from(parent.getContext()).inflate(
                R.layout.item_row, null);


        ViewHolder viewHolder = new ViewHolder(itemLayoutView);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(RecyclerAdapter.ViewHolder holder, int position) {

        holder.name.setText(dbList.get(position).getName());
        holder.email.setText(dbList.get(position).getEmail());

    }

    @Override
    public int getItemCount() {
        return dbList.size();
    }

    public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        public TextView name,email;

        public ViewHolder(View itemLayoutView) {
            super(itemLayoutView);
            name = (TextView) itemLayoutView.findViewById(R.id.rvname);
            email = (TextView)itemLayoutView.findViewById(R.id.rvemail);
            itemLayoutView.setOnClickListener(this);

        }

        @Override
        public void onClick(View v) {
            Intent intent = new Intent(context,DetailsActivity.class);

            Bundle extras = new Bundle();
            extras.putInt("position",getAdapterPosition());
            intent.putExtras(extras);

            context.startActivity(intent);
            Toast.makeText(RecyclerAdapter.context, "you have clicked Row " + getAdapterPosition(), Toast.LENGTH_LONG).show();
        }
    }
}

SecondActivity：

  public class SecondActivity extends AppCompatActivity {
    DatabaseHelpher helpher;
    List<DatabaseModel> dbList;
    RecyclerView mRecyclerView;
    private RecyclerView.Adapter mAdapter;
    private RecyclerView.LayoutManager mLayoutManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);


        helpher = new DatabaseHelpher(this);
        dbList= new ArrayList<DatabaseModel>();
        dbList = helpher.getDataFromDB();


        mRecyclerView = (RecyclerView)findViewById(R.id.recycleview);

        mRecyclerView.setHasFixedSize(true);

        // use a linear layout manager
        mLayoutManager = new LinearLayoutManager(this);
        mRecyclerView.setLayoutManager(mLayoutManager);

        // specify an adapter (see also next example)
        mAdapter = new RecyclerAdapter(this,dbList);
        mRecyclerView.setAdapter(mAdapter);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_second, menu);
        return true;
    }



    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                finish();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

布局

ActivityDetails：

 <LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:layout_scrollFlags="scroll|enterAlways" />
    </android.support.design.widget.AppBarLayout>

    <TextView
        android:id="@+id/name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="name"
        android:paddingTop="15dp"
        android:paddingLeft="20dp"
        android:textSize="36sp" />

    <TextView
        android:id="@+id/roll"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Roll"/>
    <TextView
        android:id="@+id/address"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Address"/>
    <TextView
        android:id="@+id/branch"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Branch"/>
    <TextView
        android:id="@+id/email"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Email"/>
    </LinearLayout>

ActivityMain：

  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical">
    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:layout_scrollFlags="scroll|enterAlways" />

    </android.support.design.widget.AppBarLayout>

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical" >

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal">
                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Enter Email"/>
                <EditText
                    android:id="@+id/etEmail"
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"/>

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal">
                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Enter Branch"/>
                <EditText
                    android:id="@+id/etBranch"
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"/>

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal">
                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Enter Address"/>
                <EditText
                    android:id="@+id/etAddress"
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"/>

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal">
                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Enter Roll"/>
                <EditText
                    android:id="@+id/etRoll"
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"/>

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal">
                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Enter Name"/>
                <EditText
                    android:id="@+id/etName"
                    android:layout_width="fill_parent"
                    android:layout_height="wrap_content"/>

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal">
                <Button
                    android:id="@+id/btnSubmit"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:text="uložit do databáze"
                    android:textColor="#ffffff"
                    android:background="@color/colorPrimary"/>

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_marginTop="10dp"
                android:orientation="horizontal">
                <Button
                    android:id="@+id/btngetdata"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:text="Zobrazit seznam rumů"
                    android:textColor="#ffffff"
                    android:background="@color/colorPrimary"/>

            </LinearLayout>

        </LinearLayout>
    </ScrollView>


</LinearLayout>

ActivitySecond：

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical">
    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:layout_scrollFlags="scroll|enterAlways" />
    </android.support.design.widget.AppBarLayout>
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">


        <android.support.v7.widget.RecyclerView
            android:id="@+id/recycleview"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>

    </LinearLayout>
    </LinearLayout>

item_row：

  <?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_margin="5dp"
    android:orientation="horizontal"
    card_view:cardCornerRadius="5dp"
    card_view:cardUseCompatPadding="true" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="?android:selectableItemBackground"  >


        <TextView
            android:id="@+id/rvemail"
            android:layout_width="fill_parent"
            android:layout_height="45dp"
            android:textAlignment="center"
            android:padding="10dp"
            android:gravity="right"
            android:text="Email"
            android:textColor="@android:color/black"
            android:layout_marginLeft="10dp"
             />

        <TextView
            android:id="@+id/rvname"
            android:layout_width="wrap_content"
            android:layout_height="45dp"
            android:gravity="left"
            android:padding="10dp"
            android:textAlignment="center"
            android:text="Name"
            android:textColor="@android:color/black"
            android:layout_alignParentTop="true"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true" />

    </RelativeLayout>

</android.support.v7.widget.CardView>

非常非常感谢您的帮助，我不知道如何解决插入图像和文本到一个数据库的问题，然后将它们存储在移动设备中，然后点击排，然后应用程序显示图像和文本。 PS：对不起很多代码，但我不知道该怎么做：（

Answer 1

您应该将图像保存到特定文件夹中然后将每个图像的路径插入数据库。

然后，当您想要检索图像时，查询您的数据库，并使用存储的路径找到您的图像。

有一个非常好的示例，说明当您获得路径时如何显示图像： {{3}}

Answer 2

    public class DatabaseHelpher extends SQLiteOpenHelper {
    private static final String DATABASE_NAME="student";
    private static final int DATABASE_VERSION = 1;
    private static final String STUDENT_TABLE = "stureg";
    private static final String STU_TABLE = "create table "+STUDENT_TABLE +"(name TEXT,email TEXT primary key,roll TEXT,address TEXT,branch TEXT,,image BLOB)";

    Context context;

    public DatabaseHelpher(final Context context) {
        super(context, Environment.getExternalStorageDirectory()
                + File.separator + DATABASE_NAME, null, DATABASE_VERSION);
        this.context = context;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        db.execSQL(STU_TABLE);
    }

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

        db.execSQL("DROP TABLE IF EXISTS " + STUDENT_TABLE);

        // Create tables again
        onCreate(db);
    }

    public void insertIntoDB(String name,String email,String roll,String address,String branch,byte[]image_data){
        Log.d("insert", "before insert");

        // 1. get reference to writable DB
        SQLiteDatabase db = this.getWritableDatabase();

        // 2. create ContentValues to add key "column"/value
        ContentValues values = new ContentValues();
        values.put("name", name);
        values.put("email", email);
        values.put("roll", roll);
         values.put("address", address);
        values.put("branch", branch);
        values.put("image", image_data);

        // 3. insert
        db.insert(STUDENT_TABLE, null, values);
        // 4. close
        db.close();
        Toast.makeText(context, "insert value", Toast.LENGTH_LONG);
        Log.i("insert into DB", "After insert");



    }


    public List<DatabaseModel> getDataFromDB(){
        List<DatabaseModel> modelList = new ArrayList<DatabaseModel>();
        String query = "select * from "+STUDENT_TABLE;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(query,null);
        if (cursor.moveToFirst()){
            do {
                DatabaseModel model = new DatabaseModel();
                model.setName(cursor.getString(0));
                model.setEmail(cursor.getString(1));
                model.setRoll(cursor.getString(2));
                model.setAddress(cursor.getString(3));
                model.setBranch(cursor.getString(4));
                model.setImage(cursor.getBlob(5));  //Add byte paramter in your DatabaseModel
                modelList.add(model);
            }while (cursor.moveToNext());
        }


        Log.d("student data", modelList.toString());


        return modelList;
    }



    public void deleteARow(String email){
        SQLiteDatabase db= this.getWritableDatabase();
        db.delete(STUDENT_TABLE, "email" + " = ?", new String[] { email });
        db.close();
    }
    }

将图像和一些文本字段插入SQLite数据库 - Android

2 个答案: