Change text size and color in one time?

Question

I create many activities and classes in my app. However I have a function to change font size and color in every activity. This function changes text in own activity. When I go to other activity I must change textSize and color again. How can I create a function to change TextView in many classes and activities in one shot?

My app Structure:

Main.java   main.xml/
Suad1.java  suad1.xml/
Suad2.java  suad2.xml/
Suad3.java  suad3.xml/
Suad4.java  suad4.xml/

I want to change these activity in one time. Here my code in Suad1.class.

public void ShowDialog() {
    final AlertDialog.Builder popDialog = new AlertDialog.Builder(this);
    final SeekBar seek = new SeekBar(this);
    seek.getProgress();
    seek.setMax(100);

    popDialog.setIcon(R.drawable.conp);
    popDialog.setTitle(R.string.menu_settings);
    popDialog.setView(seek);
    try {

        seek.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            public void onStartTrackingTouch(SeekBar seekBar) {
                // TODO Auto-generated method stub
            }

            public void onStopTrackingTouch(SeekBar seekBar) {
                 // TODO Auto-generated method stub
            }

            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                subtitles.setTextSize(progress);
            }
        });
    }
    catch (Exception e) {
        e.printStackTrace();
    }

    popDialog.setSingleChoiceItems(items , -1,
        new DialogInterface.OnClickListener() {
            int i;
            public void onClick(DialogInterface dialog, int item) {
                i = item;
                if(items[i] =="Blue") {
                    subtitles.setTextColor(getResources().getColor(R.color.font3));
                } else if(items[i] == "Yellow") {
                    subtitles.setTextColor(getResources().getColor(R.color.font1));
                } else if(items[i]== "Red") {
                    subtitles.setTextColor(getResources().getColor(R.color.font2));
                }
            }
        }
    );

    // Button
    popDialog.setPositiveButton("OK",
        new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(Suad1.this, "Your setting is complete", Toast.LENGTH_LONG).show();
                dialog.dismiss();
            }
        }
    );
    popDialog.create();
    popDialog.show();
}

And two more questions:

1. Can I update SeekBar when out dialog and back again?
2. Can I have two Titles or more in one AlertDialog?

Answer 1

Create a separate class with method which you can use in multiple Activities for Changing TextView text,color :

public class ChangetextAttr {


public Activity context;

public ChangetextAttr(Activity context){

        this.context=context;
}

// Create an Method for Changing TextView Attributes

public void settextViewAttr(Activity activity, TextView txtView){

   txtView.setTextSize(15);
   txtView.setTextColor(activity.getResources().getColor(R.color.font1));
   //....
}

and from Any Activity you can settextViewAttr method for setting TextView Attributes :

   ChangetextAttr obj=new ChangetextAttr(Your_Activity.this);
   obj.settextViewAttr(this,any_textview_instance);

Answer 2

Hey create a(Customized textview) class which extends TextView and do whatever you want to do for the textview like changing text color and textstyle. now use this class in all your xml's . if your class name MyTextView. then your xml should be like the following...

   <urpackage.MyTextView
    android:id="@+id/text_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    />

Answer 3

Android provides you with mechanisms already to change the appearance of widgets, via Styles and Themes.

Here is how you define a style that sets the text size and color of any view that holds text:

<style name="BigColoredText">
    <item name="android:textColor">#FF0000</item>
    <item name="android:textSize">25sp</item>
</style>

and here is how you apply it to a TextView:

<TextView style="@style/BigColoredText" .../>

Styles can only be supplied to Views at construction time, you cannot change it afterwards. However, you can programmatically change the textAppearance with is the subset of a style that refers to text attributes via:

TextView v = ...;
v.setTextAppearance(R.styles.BigColoredText);

Now, if you want all TextViews within your Activity or Application using that same style (or at least use it by default), then you need a Theme:

<style name="Theme.MyTheme" parent="@android:style/Theme">
    <item name="android:textViewStyle">@style/BigColoredText</item>
</style>

and then apply the theme to either the entire Application or one or more Activities in your manifest:

<application or activity android:theme="@style/Theme.MyTheme" .../>

Or you can change it programmatically at runtime via:

Activity activity = ...;
activity.setTheme(R.style.Theme_MyTheme);

Answer 4

To answer your questions:

1- What you need is two styles (Bold & normal) and change between the used style for Text using View.setTextAppearance. Check Android documentaion and this answer.

2- To update seekbar with a value that is unchanged from View to View, then you need to keep its progress in a shared preference for e.g. and set the progress in onResume.

3- Consider using a custom Dialog instead (you can define it in XML as you wish). Or you can include /n to have multi lines in the Title string