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Java Applets, creating an image outside of paint()


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I'm relatively new to Java programming, to a certain extent. More specifically, new to programming applets. I used to do Java programming somewhat about three years ago, but not too regularly.Anyway, I had attempted to create an image and display it to the screen outside of the paint() function. It is in a manually created method called "update_text".

m_letter1= getImage(getCodeBase(), ut_character);m_graphics1.drawImage(m_letter1, 21, 21, this);

This executes at the end of the update_text method. However, I get a NullExceptionError when it runs, and therefore the image is not displayed. Here (before the above code is executed), apparently m_letter1 and m_graphics1 are null. ut_character is not. After executing the above code, only m_graphics1 is null.Outside of the update_text method, I defined the graphics and image variables (m_letter1 and m_graphics1):

private Image m_letter1;private Graphics m_graphics1;

This is the error I get:

Exception in thread "Thread-5" java.lang.NullPointerExceptionat base.Main.update_text(Main.java:113)at base.Main.run(Main.java:156)at java.lang.Thread.run(Thread.java:619)

Main.java:113: m_graphics1.drawImage(m_letter1, 21, 21, this);Main.java.156: update_text();Anyway, I was wondering if there was a way to fix this. I can't necessarily use the paint method, I'm pretty sure, since I don't want all of this displayed exactly at run time.Any help would be much appreciated.

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NullPointerExceptions usually occur when you try to reference something that is null. That image or Graphics class may need to be created in memory by using the "new" keyword.Like:

m_letter1 = new Image();

.Then you would use the getImage method. I believe those two classes are created like that so check the documentation for constructors. Image Class

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