Question

I have a custom view in my app that I draw using the onDraw() function in the View. Also it needs some data from the ACtivity to draw the graphic. So instead of using the standard setContentView(R.layout.myview) I am using the following –

MyView mv = new MyView(this, userData);
setContentView(mv);

This seemed to work until I added a textview above the customview. Then I realized that the above code does not show the textview at all. Also the onFinishInflate() is never called. Do I have to inflate the layout myself in this case? If so do I have to call the onDraw() function myself too?

Thanks,
– P

Answer 1

What you should have here is a layout that contains the TextView and your MyView and then inside your activity, find your custom view and pass in your user data. Your MyView can then use this during its onDraw(). Perhaps something like this:

res/layout/main.xml:

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="veritcal">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Hello World" />
    <my.package.MyView
        android:id="@+id/myview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

src/my/package/MyView.java:

public class MyView extends View {
    UserData mUserData = null;
    public void setUserData(userData) {
        mUserData = userData;
    }

    @Override
    protected void onDraw(Canvas canvas) {
        performCustomDrawingWithUserData(mUserData);
        super.onDraw(canvas);
    }

}

src/my/package/MyActivity.java:

public class MyActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // pass the user data into myview here.
        MyView myView = (MyView) findViewById(R.id.myview);
        myView.setUserData(userData);
    }

}