Hi Justin, my main.xml looks as follows:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/ android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center_horizontal" android:text="@string/text_a" /> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center_horizontal" android:text="@string/text_b" /> <Button android:id="@+id/flag_button" android:text="@string/button_string1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" /> </LinearLayout> I'd really like to get around having to declare a separate imageView in the XML layout. Isn't there a way of instantiating such an object by hand and adding it to the application's layout at runtime? Best, Sven On Oct 13, 5:28 am, Justin Anderson <[email protected]> wrote: > What does the XML for your res/layout/main.xml look like? > > Thanks, > Justin > > ---------------------------------------------------------------------- > There are only 10 types of people in the world... > Those who know binary and those who don't. > ---------------------------------------------------------------------- > > On Mon, Oct 12, 2009 at 9:28 AM, Sven <[email protected]> wrote: > > > Hi, > > > I want to add an ImageView to my layout when a button has been > > pressed. Sadly, I cannot get a handle to the main application's > > linearlayout, I always get a null pointer error when trying to > > retrieve the layout using findViewByID. > > > Here's the code that ought to display the image when button b has been > > pressed, but I think I have missed something obious: > > > package com.foo.bar; > > > import android.app.*; > > import android.os.Bundle; > > import android.view.*; > > import android.view.ViewGroup.LayoutParams; > > import android.widget.*; > > import android.content.*; > > import android.util.Log; > > > public class AndroidTest extends Activity { > > /** Called when the activity is first created. */ > > �...@override > > public void onCreate(Bundle savedInstanceState) { > > super.onCreate(savedInstanceState); > > setContentView(R.layout.main); > > > // assign flag.png to the button, loading correct flag image for > > current locale > > Button b; > > b = (Button)findViewById > > (R.id.flag_button) ;//.setBackgroundDrawable(this.getResources > > ().getDrawable(R.drawable.developers)); > > > // build dialog box to display when user clicks the flag > > AlertDialog.Builder builder = new AlertDialog.Builder(this); > > builder.setMessage(R.string.dialog_text) > > .setCancelable(false) > > .setTitle(R.string.dialog_title) > > .setPositiveButton("Done", new > > DialogInterface.OnClickListener() { > > public void onClick(DialogInterface dialog, int id) { > > dialog.dismiss(); > > } > > }); > > final AlertDialog alert = builder.create(); > > > // set click listener on the flag to show the dialog box > > b.setOnClickListener(new View.OnClickListener() { > > public void onClick(View v) { > > // alert.show(); > > ImageView image; > > image = new ImageView(v.getContext()); > > image.setImageDrawable(v.getResources().getDrawable > > (R.drawable.developers)); > > > LinearLayout main = (LinearLayout) > > AndroidTest.this.findViewById(R.layout.main); > > // some debug code > > if (main == null) > > { > > Log.v("abc", "Main is null"); > > } > > else > > { > > main.addView(image, 200, 200); > > } > > } > > }); > > > } > > } --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Beginners" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-beginners?hl=en -~----------~----~----~----~------~----~------~--~---
