How to switch image while program is running?

[MJLcodee]

So we know how to make a certain image. You just write into the xml:
android:src="@drawable/myimage"

But how do you change this source image while the program is running, i.e. inside the Java code?

I have essentially a listactivity which makes the same image appear multiple times. Now I'd like to make it so that, for each item it lists:
if(condition1)
{make image1 appear there}
else if(condition2)
{make image2 appear there}


I tried stuff like
findViewById(R.id.ImageView01).setBackgroundDrawab le(drawable/image2);
(or do I have something mixed up, what's the backgrounddrawable? Cause I didn't see any other drawable you could "set")

and I tried findViewById(R.id.ImageView01)).setVisibility(0); , figuring I could cheat and just put the two images side by side, and make the one invisible that doesn't apply.
But both these attempts just make the program crash.

Any help would be appreciated, thanks.

[chandan]

Try the following:

findViewById(R.id.ImageView01).fly.setBackgroundDr awable(getResources().getDrawable(R.drawable.your_ image_name));

[MJLcodee]

It says "fly cannot be resolved or is not a field". Do I need to import something?

[chandan]

Hi,

I'm sorry. I just copied the code from my editor..remove "fly" i.e as below:

findViewById(R.id.ImageView01).setBackgroundDr awable(getResources().getDrawable(R.drawable.your_ image_name));


I'm sure it will work:-)

[chandan]

To make you clear: "fly" is a variable of type "ImageView" referring to the image view in xml file.

i.e suppose you have set id of image view in xml as : android:id="@+id/ImageView01"

and then in program you can have variable referring to it:

ImageView fly=(ImageView )findViewById(R.id.ImageView01);

fly.setBackgroundDrawable(getResources().getDrawab le(R.drawable.your_image_name));
/*you can use fly instead of using "findViewById(R.id.ImageView01)" every time.
* Also declare it as class member variable in order to access in all the methods in that *class.
*/

[MJLcodee]

Thanks, we're getting closer to the problem already. It compiles now. The only problem is, it still crashes. I dissected and debugged the code to find out where the problem is, maybe you can help me? Here's the result:

int myid = R.id.ImageView01; //= 2131099649
View myview = findViewById(myid); //= null (so here's the problem. But why would this be null?)
ImageView fly=(ImageView)myview; //=null (makes sense, since the above was null)
Drawable drawi = getResources().getDrawable(R.drawable.mypic); //= BitmapDrawable (id=830060997664)
fly.setBackgroundDrawable(drawi); //"source not found", crash.

[chandan]

That is crazy:-).

Make sure you have set id to the ImageView in xml file as below:

android:id="@+id/ImageView01"

If you have already did, give some other name and try.

[chandan]

Got the bug:

change View myview = findViewById(myid); to View myview = (View)findViewById(myid);

If it still fails, do not use View. ie:
ImageView fly=(ImageView)findViewById(myid);

[MJLcodee]

Still didn't work. :/
I tried changing that part to View myview = (View)findViewById(myid); still returns null
Already tried ImageView fly=(ImageView)findViewById(myid); , it returns null too

And I tried changing the image id, to android:id="@+id/boing".

Here's a message I got during debugging when I "went into" the line where it assigns myview or the one that assigns fly:
"The JAR of this class file belongs to container 'Android 1.6' which does not allow modifications to source attachments on its entries."

Could that have something to do with it? That I'm using the wrong version for this command?

[chandan]

Ok,,

Make sure that in manifest file, the below line has been set properly..

<uses-sdk android:minSdkVersion="4" />

/* 3 for 1.5
* 4 for 1.6
* 5 for 2.0 and so on..
*/