I have an application with a common Header in all layouts. I want that whenever the user clicks at the the ImageView with id btn_home
, the app will go back to a specific activity, my "Main" for instance.
What is the best way to do that?
I know that I can define the onClick(View v)
for every activity, but maybe there is a better way to do that. Even making every activity be some (via heritage) other that has the onClick(View v)
defined sounds bad.
header.xml
<RelativeLayout ...>
<RelativeLayout android:id="@+id/relativeLayout1" ...>
<ImageView android:id="@+id/logo_cats"></ImageView>
<ImageView android:id="@+id/btn_home" ...></ImageView>
</RelativeLayout>
</RelativeLayout>
every layout
...
<include layout="@layout/header" android:id="@开发者_开发百科+id/header"
android:layout_height="wrap_content" android:layout_width="fill_parent" />
...
You can make a custom component out of your header and define 'onClick()' in it. For example, make a new class Header
that would extend a RelativeLayout and inflate your header.xml there. Then, instead of <include>
tag you would use <com.example.app.Header android:id="@+id/header" ...
. No code duplication and the header becomes totally reusable.
UPD: Here's some code examples
header.xml:
<merge xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView android:id="@+id/logo" .../>
<TextView android:id="@+id/label" .../>
<Button android:id="@+id/login" .../>
</merge>
activity_with_header.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" ...>
<com.example.app.Header android:id="@+id/header" .../>
<!-- Other views -->
</RelativeLayout>
Header.java:
public class Header extends RelativeLayout {
public static final String TAG = Header.class.getSimpleName();
protected ImageView logo;
private TextView label;
private Button loginButton;
public Header(Context context) {
super(context);
}
public Header(Context context, AttributeSet attrs) {
super(context, attrs);
}
public Header(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public void initHeader() {
inflateHeader();
}
private void inflateHeader() {
LayoutInflater inflater = (LayoutInflater) getContext()
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
inflater.inflate(R.layout.header, this);
logo = (ImageView) findViewById(R.id.logo);
label = (TextView) findViewById(R.id.label);
loginButton = (Button) findViewById(R.id.login);
}
ActivityWithHeader.java:
public class ActivityWithHeader extends Activity {
private View mCreate;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_with_header);
Header header = (Header) findViewById(R.id.header);
header.initHeader();
// and so on
}
}
In this example, Header.initHeader() can be moved inside Header's constructor, but generally this method provides a nice way to pass on some useful listeners. Hope this will help.
Extend the Activity class and build a MyActivity class for example. In this MyActivity class you could include the code for the onClick.
Now create a layout that just holds your header. Include that layout in your activity layouts.
Extend all your activities from MyActivity - that's it.
If you need the same behaviour in ListActivities create a MyListActivity as well.
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