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androidtabwidgettabactivity

Controlling Tab colour-state / size in a TabActivity?


Ok, this is driving me nuts - I've searched all of the references and examples I can find and I still seem to be missing something really obvious. These are the tabs for a 7-day TV Guide (not normally with the red arrow, obviously :) )...

enter image description here

What I need to know is what is the object (View or Drawable I assume) that makes up the main body/background of a Tab itself? (as indicated by the red arrow) and how do I access it or have it automatically change its state colour to a list of my choice? Also, how can I get the state colour of the indicator TextView to follow suit?

Example: In the capture above, it's readable because I've set the textColor to a static grey (instead of the bright white which disappeared on a selected tab). But I want it to automatically become black text on white tab (selected) and bright white text on black (for unselected).

All help gratefully received.


Solution

  • The view which represents each tab can be changed using

    setIndicator(View)
    

    I've been using this code to build each tab :

    View view = buildTabView(this, "Friday");
    TabHost.TabSpec spec = tabHost.newTabSpec("cat1").setIndicator(view).setContent(intent);
    tabHost.addTab(spec);
    
    public static LinearLayout buildTabView(Context context, String label){
        LayoutInflater li = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);          
        final LinearLayout ll = (LinearLayout)li.inflate(R.layout.tab, null);
    
        // the following lines will change the tabs size depending on the label (text) length.
        // the longer tab text - the wider tabs
        LinearLayout.LayoutParams layoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, label.length() + 1);
        ll.setLayoutParams(layoutParams);
    
        final TextView tv = (TextView)ll.findViewById(R.id.tab_tv);         
        tv.setOnTouchListener(new OnTouchListener() {               
            public boolean onTouch(View v, MotionEvent event) {
                ll.onTouchEvent(event);
                return false;
            }
        });
    
        tv.setText(label);          
        return ll;
    }
    

    And here comes layout/tab.xml

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:background="@drawable/tab_bg_selector"
      android:clickable="true"
      >
    
      <TextView
      android:id="@+id/tab_tv"
      android:layout_width="wrap_content"
      android:layout_height="33dip"
      android:text="Text 1"
      android:textStyle="bold"
      android:textSize="16dip"
      android:gravity="center"
      android:textColor="@drawable/tab_color_selector"
      android:layout_weight="1.0"
      android:clickable="true"
      />
    
    </LinearLayout>
    

    Note that LinearLayout has a selector on it's background (to change backround, obviously :) ), and the TextView has a selector on the textColor (to change the text color when selected / pressed etc.). It this way you can make the text look black when tab is pressed, and white when it is not :)