This is what i'm trying to achieve:
Use a TextView in a TabWidget (i.e. call
TabHost.TabSpec.setIndicator(View)
instead ofTabHost.TabSpec.setIndicator(String)
).And i want to configure that TextView in XML instead of building it programatically.
So initially, in my layout XML, i had:
<TabHost
android:id="@+id/mainTabHost"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/ap开发者_如何学Pythonk/res/android">
<TabWidget android:id="@android:id/tabs" android:layout_width="fill_parent" android:layout_height="30px"/>
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingTop="30px">
</FrameLayout>
</TabHost>
Now i want to put in the TextView configuration somewhere. It does not actually "belong" nested anywhere within the layout hierarchy. But, since the layout XML have to be a valid XML of course, it can't have more than one root element. So i'm forced to nest the TextView somewhere. Hence i just put it one level below the root (TabHost):
<TabHost
android:id="@+id/mainTabHost"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<TabWidget android:id="@android:id/tabs" android:layout_width="fill_parent" android:layout_height="30px"/>
<TextView
android:id="@+id/tvTabIndicatorPreferences"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:text="@string/tab_name_preferences"/>
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingTop="30px">
</FrameLayout>
</TabHost>
And in my code i do:
final TabHost mainTabHost = (TabHost) this.findViewById(R.id.mainTabHost);
mainTabHost.setup();
final TextView tvTabIndicatorPreferences = (TextView) this.findViewById(R.id.tvTabIndicatorPreferences);
final TabHost.TabSpec tabSpecPreferences = mainTabHost.newTabSpec("tabPreferences");
tabSpecPreferences.setIndicator(tvTabIndicatorPreferences);
tabSpecPreferences.setContent(R.id.scrlTblPreferences);
mainTabHost.addTab(tabSpecPreferences);
but there's a problem here. When i try to run the application, i get an exception which says
Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
which is by all means logical and reasonable. The TextView is already a child of the TabHost. i can't just set it as the child of another element. (Note: Putting the TextView nested under the TabWidget yields the same thing.)
so i'm forced to call mainTabHost.removeView(tvTabIndicatorPreferences)
before calling the setIndicator
.
It works actually, but this way of doing feels very wrong to me. Firstly, i have to put the TextView in the XML where it didn't belong, then in the code remove it from where it didn't belong before using it.
In such a scenario, what's the Right Way to achieve this?
Step #1: Pull the TextView
out into a separate layout file (e.g., res/layout/indicator.xml
).
Step #2: Call tabSpecPreferences.setIndicator(getLayoutInflater().inflate(R.layout.indicator, null));
Step #3: There is no Step #3.
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