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I wanted to try creating a TableRow with a small group of TextViews, each of them holding a primitive String data. I thought, maybe if I store an ArrayList of these TableRows, and if successfully read/write back and forth, I would simplify a lot of time to create a datasheet or a chart on the Android screen.

By the look of it, I feel like I would have to make a lot of subclasses of the Views, and implement Serializable to all of them. It is totally beyond my ability.

My main question is: Is it possible to store a group of TextView into a TableRow, create an array full of TableRows, and individually add each one of them into a TableLayout?

So far, I can't go beyond saving the data with the use of ObjectOutputStream, as it keeps throwing NotSerializableException, InvalidAccessException, IllegalAccessException, EOFException, IOException, etc., all sorts of different exceptions.

If my concept is not very good, may I ask where should I need to rethink this? What should I change, and how should I store groups of data? Thanks in advance.

Without further ado, here's my code that I use to try and save an ArrayList of TableRows, and all the mumbo-jumbo I've been working on for the past 12 hours, non-stop.

package tt.tt;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.io.StreamCorruptedException;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;

public class Test extends Activity implements OnClickListener, Serializable {

    private static final long serialVersionUID = 2466231508464769438L;

    public class Format implements Serializable {
        private static final long serialVersionUID = 1L;
        public String name;
        public long points;
        public int position;
    }

    List<Format> formats = new ArrayList<Format>();
    TableRow row;
    TableLayout layout;

    @Override
    public void onCreate(Bundle b) {
        super.onCreate(b);
        setContentView(R.layout.table);
        layout = (TableLayout) this.findViewById(R.id.table);
        Button make = (Button) this.findViewById(R.id.make);
        make.setOnClickListener(this);
        Button retrieve = (Button) this.findViewById(R.id.retrieve);
        retrieve.setOnClickListener(this);
    }

    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.make:
                make();
                break;
            case R.id.retrieve:
                retrieve();
                break;
        }
    }

    public void make() {
        Random r = new Random();
        Format f = new Format();
        f.name = r.toString();
        f.points = r.nextLong();
        f.position = r.nextInt(10);
        formats.add(f);

        FileOutputStream out;
        try {
            out = this.openFileOutput("format", Activity.MODE_PRIVATE);
            ObjectOutputStream output = new ObjectOutputStream(new BufferedOutputStream(out));
            output.writeObject(formats);
            output.flush();
            output.close();
        }
        catch (FileNotFoundException e) {
            Log.d("Test", "Can't save data", e);
        }
        catch (IOException e) {
            Log.d("Test", "Can't save data", e);
        }

        TextView text = new TextView(this);
        text.setText(Integer.toString(f.position));
        row = new TableRow(this);
        row.addView(text, 0, TableRow.LayoutParams.WRAP_CONTENT);
        text = new TextView(this);
        text.setText(f.name);
        row.addView(text, 1, TableRow.LayoutParams.WRAP_CONTENT);
        text = new TextView(this);
        text.setText(Long.toString(f.points));
        row.addView(text, 2, TableRow.LayoutParams.WRAP_CONTENT);

        layout.addView(row);
    }

    public void retrieve() {
        layout.removeAllViews();
        FileInputStream in;
        try {
            in = this.openFileInput("format");
            ObjectInputStream input = new ObjectInputStream(new BufferedInputStream(in));
            List<Format> temp = (List<Format>) input.readObject();
            input.close();
        }
        catch (FileNotFoundException e) {
            Log.d("Test", "Can't load data", e);
        }
        catch (StreamCorruptedException e) {
            Log.d("Test", "Can't load data", e);
        }
        catch (IOException e) {
            Log.d("Test", "Can't load data", e);
        }
        catch (ClassNotFoundException e) {
            Log.d("Test", "Can't load data", e);
        }
    }

}

Unfortunately, when I reach this line here:

output.writeObject(formats);

It throws out an error, retrieved from Logcat:

09-22 14:50:43.658: D/Test(29362): Can't save data
09-22 14:50:43.658: D/Test(29362): java.io.NotSerializableException: android.widget.TableLayout
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeNewObject(ObjectOutputStream.java:1364)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObjectInternal(ObjectOutputStream.java:1671)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1517)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1481)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeFieldValues(ObjectOutputStream.java:979)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:368)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeHierarchy(ObjectOutputStream.java:1074)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeNewObject(ObjectOutputStream.java:1404)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObjectInternal(ObjectOutputStream.java:1671)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1517)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1481)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeFieldValues(ObjectOutputStream.java:979)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:368)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeHierarchy(ObjectOutputStream.java:1074)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeNewObject(ObjectOutputStream.java:1404)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObjectInternal(ObjectOutputStream.java:1671)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1517)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1481)
09-22 14:50:43.658: D/Test(29362):  at java.util.ArrayList.writeObject(ArrayList.java:644)
09-22 14:50:43.658: D/Test(29362):  at java.lang.reflect.Method.invokeNative(Native Method)
09-22 14:50:43.658: D/Test(29362):  at java.lang.reflect.Method.invoke(Method.java:511)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeHierarchy(ObjectOutputStream.java:1053)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeNewObject(ObjectOutputStream.java:1404)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObjectInternal(ObjectOutputStream.java:1671)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1517)
09-22 14:50:43.658: D/Test(29362):  at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1481)
09-22 14:50:43.658: D/Test(29362):  at tt.tt.Test.make(Test.java:75)
09-22 14:50:43.658: D/Test(29362):  at tt.tt.Test.onClick(Test.java:55)
09-22 14:50:43.658: D/Test(29362):  at android.view.View.performClick(View.java:3549)
09-22 14:50:43.658: D/Test(29362):  at android.view.View$PerformClick.run(View.java:14400)
09-22 14:50:43.658: D/Test(29362):  at android.os.Handler.handleCallback(Handler.java:605)
09-22 14:50:43.658: D/Test(29362):  at android.os.Handler.dispatchMessage(Handler.java:92)
09-22 14:50:43.658: D/Test(29362):  at android.os.Looper.loop(Looper.java:154)
09-22 14:50:43.658: D/Test(29362):  at android.app.ActivityThread.main(ActivityThread.java:4945)
09-22 14:50:43.658: D/Test(29362):  at java.lang.reflect.Method.invokeNative(Native Method)
09-22 14:50:43.658: D/Test(29362):  at java.lang.reflect.Method.invoke(Method.java:511)
09-22 14:50:43.658: D/Test(29362):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
09-22 14:50:43.658: D/Test(29362):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
09-22 14:50:43.658: D/Test(29362):  at dalvik.system.NativeStart.main(Native Method)
tom_mai78101
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1 Answers1

0

Figured it out, after a long Starcraft 2 session. The real solution to all of this problem, is to not implement the interface, Serializable, to a nested class, regardless of public, protected, or private.

I swear, if you implement that interface into your nested class, it will also try to Serialize other elements in the outer class, which in this case, is the Activity class. Of course, it will fail. You can't Serialize an Activity class, with so many non-Serializable members and instances, it's impossible to make this to work if you do that.

That's all.

package tt.tt;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.StreamCorruptedException;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;

public class Test extends Activity implements OnClickListener {

    List<Format> formats = new ArrayList<Format>();
    TableRow row;
    TableLayout layout;

    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.make:
                make();
                break;
            case R.id.retrieve:
                retrieve();
                break;
        }
    }

    @Override
    public void onCreate(Bundle b) {
        super.onCreate(b);
        setContentView(R.layout.table);
        layout = (TableLayout) this.findViewById(R.id.table);
        Button make = (Button) this.findViewById(R.id.make);
        make.setOnClickListener(this);
        Button retrieve = (Button) this.findViewById(R.id.retrieve);
        retrieve.setOnClickListener(this);
    }

    public void make() {
        Random r = new Random();
        Format f = new Format();
        f.position = r.nextInt(10);
        f.name = r.toString();
        f.points = r.nextLong();
        formats.add(f);

        FileOutputStream out;
        try {
            out = this.openFileOutput("format", Activity.MODE_PRIVATE);
            ObjectOutputStream output = new ObjectOutputStream(new BufferedOutputStream(out));
            output.writeObject(formats);
            output.flush();
            output.close();
        }
        catch (FileNotFoundException e) {
            Log.d("Format", "Can't save data", e);
        }
        catch (IOException e) {
            Log.d("Format", "Can't save data", e);
        }
    }

    public void retrieve() {
        formats.clear();
        FileInputStream in;
        try {
            in = this.openFileInput("format");
            ObjectInputStream input = new ObjectInputStream(new BufferedInputStream(in));
            formats = (ArrayList<Format>) input.readObject();
            input.close();
        }
        catch (FileNotFoundException e) {
            Log.d("Format", "Can't load data", e);
        }
        catch (StreamCorruptedException e) {
            Log.d("Format", "Can't load data", e);
        }
        catch (IOException e) {
            Log.d("Format", "Can't load data", e);
        }
        catch (ClassNotFoundException e) {
            Log.d("Format", "Can't load data", e);
        }
        int count = 0;
        while (count < formats.size()) {
            Format f = formats.get(count);
            row = new TableRow(this);
            TextView temp = new TextView(this);
            TableRow.LayoutParams params = new TableRow.LayoutParams(TableRow.LayoutParams.WRAP_CONTENT, TableRow.LayoutParams.WRAP_CONTENT, 1f);
            temp.setText(Integer.toString(f.position));
            row.addView(temp, 0, params);
            temp = new TextView(this);
            temp.setText(f.name);
            row.addView(temp, 1, params);
            temp = new TextView(this);
            temp.setText(Long.toString(f.points));
            row.addView(temp, 2, params);
            layout.addView(row);
            count++;
        }
    }
}

And the Format class:

package tt.tt;

import java.io.Serializable;

public class Format implements Serializable {
    private static final long serialVersionUID = 1L;
    public String name;
    public long points;
    public int position;

    @Override
    public String toString() {
        return new StringBuilder().append(Integer.toString(position)).append("    ").append(name).append("     ").append(points).toString();
    }
}
tom_mai78101
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