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Java

Posted by Kaytlynn Ransom
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Kaytlynn Ransom
Python Web Development Techdegree Student 11,409 Points

Why won't my for-loop generate a shape repeatedly?

I'm writing a program that creates a thermometer, and I want to make it so that the thermometer slowly fills up until it reaches the right temperature. To accomplish this, I've created a for loop that adds a red rectangle over and over again. This is the code:

public void drawTherm() { GRect colorRed = new GRect(THERM_WIDTH, 30); colorRed.setFilled(true); colorRed.setColor(Color.red); for(int i=0; i<THERM_OVAL; i++){ add(colorRed, 353, 400-(i*3));
pause(1000); } }

The problem is that instead of adding multiple GRects, it only adds a single one and then moves that single GRect up the thermometer stem. Does anyone have any ideas as to why it won't create multiple shapes?

1 Answer

Chris Jones
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Chris Jones
Java Web Development Techdegree Graduate 23,933 Points

Instead of adding multiple rectangles, could you add one rectangle, but in your loop increase the height of the one rectangle?

Something like this:

public void drawTherm() { 

    GRect colorRed = new GRect(THERM_WIDTH, 30); 
    colorRed.setFilled(true); 
    colorRed.setColor(Color.red); 

    add(colorRed, 353, 400);

    for(int i=0; i<THERM_OVAL; i++) { 
        colorRed.adjustHeight(i); //new method...see below
        pause(1000); 
    }
}

public void adjustHeight(int newHeight) {
    this.height += newHeight;
}
Kaytlynn Ransom
.a{fill-rule:evenodd;}techdegree
Kaytlynn Ransom
Python Web Development Techdegree Student 11,409 Points

That's brilliant! I'll give it a shot.

Chris Jones
.a{fill-rule:evenodd;}techdegree seal-36
Chris Jones
Java Web Development Techdegree Graduate 23,933 Points

Glad to help! I hope it works!

I just realized the adjusteHeight method won't increase by 1 the way I wrote it. It should look like this:

public void adjustHeight(int newHeight) {
    this.height = newHeight;
}