Adding Controls using Java code

Usually more accustomed to the use of XML files to add layouts and controls, the use of Java code in the activity to add controls is also a way, the following simple example: two.

1, Addcontentview

The Addcontentview function is similar to Setcontentview () to initialize the layout for activity:

1  Public classMainactivityextendsActivity {2 3 @Override4     protected voidonCreate (Bundle savedinstancestate) {5         Super. OnCreate (savedinstancestate);6         //Setcontentview (r.layout.activity_main);7TextView tv=NewTextView (Getapplicationcontext ());8Tv.settext ("Hello world1");9 Tv.setbackgroundcolor (color.gray);Ten tv.setgravity (gravity.center); One         intx=layoutparams.match_parent; A         inty=layoutparams.wrap_content; -Linearlayout.layoutparams params=Newlinearlayout.layoutparams (x, y); -          This. Addcontentview (TV, params); the          -          -     } -}

Adding controls in Java code can also set various properties, such as Settext,setbackgroundcolor in the example. Effect:

2, AddView

AddView adds a child control based on the parent control, similar to adding a control to the XML file:

 Public class extends Activity {    @Override    protectedvoid  onCreate (Bundle savedinstancestate) {         Super . OnCreate (savedinstancestate);        Setcontentview (R.layout.activity_main);         = (linearlayout) Findviewbyid (r.id.ll);         New TextView (Getapplicationcontext ());        Tv.settext ("Hello world2");        Tv.setbackgroundcolor (Color.gray);        Tv.setgravity (gravity.center);        Ll.addview (TV);    }}

XML file:

1 <LinearLayoutxmlns:android= "Http://schemas.android.com/apk/res/android"2 Xmlns:tools= "Http://schemas.android.com/tools"3 Android:id= "@+id/ll"4 Android:layout_width= "Match_parent"5 Android:layout_height= "Wrap_content"6 android:orientation= "vertical" >7 8 </LinearLayout>

You can also add various properties of a control. Effect:

Adding Controls using Java code