How to create an Array that contains images in java?

Question

I need to create an array of images. when I try to do the getGraphics method of the Graphics class to access the Image I created in the array index it throws the java.lang.NullPointerException error even though a few lines above I created the image in that index

I tried changing the index and changing the condition of the foor loop, but it still enters the loop only once and says that the array in index 0 is null.

private Image[] frames = new Image[100];
for (int index = 0; index < frames.length; index++){
        if (frames[index] == null) 
        {
            frames[index] = this.createImage(SCREEN_WIDTH, SCREEN_HEIGHT);
        }

        Graphics graphic = frames[index].getGraphics();

I expect the array to be full of images at the end, in order to paint them and finish the job.

@QingfeiYuan It is presumably createImage from java.awt.Component. — David Conrad, Aug 22 '19 at 21:23
What is the context in which you're calling this? Are you inside a component of some kind? What kind? Has it been added to a container? Has that container been shown on the screen? — David Conrad, Aug 22 '19 at 21:36
In any case, `createImage` only works once the component is displayable. If you want an image you can draw on outside of that context, try `BufferedImage`. — David Conrad, Aug 22 '19 at 21:41

score -1 · Answer 1 · answered Aug 22 '19 at 19:57

-1

you can use following code:

ArrayList array = new ArrayList ();

and you can add Image like this:

array.add(BitmapFactory.decodeFile("file_path")); //there is many Prototypes for decodeFile

then you can use Bitmap like this:

ImageView image = (ImageView) findViewById(R.id.ImageView); image.seImageBitmap(array.get(0));

answered Aug 22 '19 at 19:57

alidoost .h

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OP said array, not ArrayList. – David Conrad Aug 22 '19 at 21:21
use : Bitmap[] array = new Bitmap[100]; – alidoost .h Aug 23 '19 at 06:13

How to create an Array that contains images in java?

1 Answers1