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How to save state with onSaveInstanceState and onRestoreInstanceState when changing orientation

I read almost the entire article on onSaveInstanceState and onRestoreInstanceState in stack overflow, but I cannot solve my problem.

I have a text view and a button in my main.java, and when you click on the value of the variable button ( a is an int variable), it will increase and appear in the text view, but when I rotate my phone (change orientation), the text view is reset .

I override onSaveInstanceState and onRestoreInstanceState, but this does not work. one more thing, i have a special layout-land.xml file for landscape view.

here is my code

 import android.app.Activity; 
 import android.graphics.Typeface; 
 import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
 import android.widget.TextView;

 public class main extends Activity {
     /** Called when the activity is first created. */   
   public int a = 0;     
   public String fonts="TAHOMA.TTF";

   TextView tv = (TextView) findViewById(R.id.salavat);      
   Button b = (Button) findViewById(R.id.showsalavat);

   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
       b.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View arg0) {
               a++;
               tv.setText(""+a);
            }
       });
   }
   @Override        
   protected void onSaveInstanceState(Bundle SavedInstanceState) {
      super.onSaveInstanceState(SavedInstanceState);            
      SavedInstanceState.putInt("salavat-count", a);
   }
   @Override    
   protected void onRestoreInstanceState(Bundle savedInstanceState) {
       super.onRestoreInstanceState(savedInstanceState);     
       a= savedInstanceState.getInt ("salavat-count");   
   } 
}

and here is my main.xml

      

    <TextView
        android:id="@+id/shoma"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="right"
        android:text="@string/shoma"
        android:textSize="20sp" />

    <Button
        android:id="@+id/showsalavat"
        android:layout_width="fill_parent"
        android:layout_height="150dp"
        android:text="+"
        android:textSize="100sp" />

    <TextView
        android:id="@+id/eltemas"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="55dp"
        android:text="@string/eltemas" />

    <TextView
        android:id="@+id/salavat"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:textSize="35sp" />

    <TextView
        android:id="@+id/ferestade"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="24dp"
        android:text="@string/salavat"
        android:textSize="20sp" />

</LinearLayout>

I really need some help. I really appreciate your help.

+3
5

, .

public class MainActivity extends Activity 
{

    protected void onSaveInstanceState(Bundle outState) 
    {
        super.onSaveInstanceState(outState);
        System.out.println("TAG, onSavedInstanceState");

        final TextView text = (TextView)findViewById(R.id.textView1);
        CharSequence userText = text.getText();
        outState.putCharSequence("savedText", userText);
    }
    protected void onRestoreInstanceState(Bundle savedState) 
    {       
        System.out.println("TAG, onRestoreInstanceState");
        final TextView text = (TextView)findViewById(R.id.textView1);
        CharSequence userText = savedState.getCharSequence("savedText");
        text.setText(userText);
    }
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final String name = "5";

        final TextView show = (TextView)findViewById(R.id.textView1);
        Button btn = (Button)findViewById(R.id.button1);
        btn.setOnClickListener(new View.OnClickListener() 
        {

            public void onClick(View v) 
            {
                // TODO Auto-generated method stub

                show.setText(name);

            }
        });
    }
}
+5

freezesText="true"

http://developer.android.com/reference/android/R.attr.html#freezesText

 <TextView
    android:id="@+id/eltemas"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:freezesText="true"/>

:

TextView yourTextView;

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

    yourTextView = (TextView) findViewById(R.id.your_textview);

}

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        outState.putString("YourTextViewTextIdentifier", yourTextView.getText().toString());

        super.onSaveInstanceState(outState);
    }

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

        yourTextView.setText(savedInstanceState.getString("YourTextViewTextIdentifier"));
    }

, , , .

, . , , , ( ) .

  private static class State implements Serializable {

    private static final String STATE = "com.your.package.classname.STATE";

    private String yourTextViewText;

    public State(String yourTextViewText) {
        this.yourTextViewText = yourTextViewText;
    }

    public String getYourTextViewText() {
        return yourTextViewText;
    }
}

@Override
protected void onSaveInstanceState(Bundle outState) {
    State s = new State(yourTextView.getText().toString());

    outState.putSerializable(State.STATE, s);

    super.onSaveInstanceState(outState);
}

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

    State s = (State) savedInstanceState.getSerializable(State.STATE);

    yourTextView.setText(s.getYourTextViewText());
}
+7

. .

@Override   
protected void onRestoreInstanceState(Bundle savedInstanceState) {
  super.onRestoreInstanceState(savedInstanceState);
  a = savedInstanceState.getInt ("salavat-count");
  tv.setText(""+a);
}
0

?

,

<activity android:name="package.subpackage.xptoactivity" android:configChanges="orientation"></activity>

, ,

0

An abandoned but serious mistake. You must first pass the data to onSavedInstanceState () and call onSavedInstanceState (). If you think about it, you'll find that it is useless to call onSavedInstanceState before transferring the data you want to save. it will not save an instance of activity, since onSavedInstanceState () is called earlier .. It should be as follows:

  @Override
  protected void onSaveInstanceState(Bundle SavedInstanceState) 
   {           
  SavedInstanceState.putInt("salavat-count", a);
  super.onSaveInstanceState(SavedInstanceState); 
   }
0
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