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Start your free trialBritt Danzer
19,539 PointsTrying to add a previous button to the project but it isn't working. Just asking to be pointed in the right direction
Code for Buttons
public class FunFactsActivity extends AppCompatActivity implements OnClickListener {
//Declare our view variables
private TextView factTextView;
public static final String TAG = FunFactsActivity.class.getSimpleName();
private ColorWheel colorWheel = new ColorWheel();
private Button showFactButton;
private Button previousFactButton;
private FactBook factBook = new FactBook();
private RelativeLayout relativeLayout;
public static final List<Integer> factNumbers = new ArrayList<Integer>();
public static final List<Integer> previousColors = new ArrayList<Integer>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fun_facts);
//Assign the Views from the layout file to corresponding variables
factTextView = findViewById(R.id.factTextView);
relativeLayout = (RelativeLayout) findViewById(R.id.relativeLayout);
showFactButton = findViewById(R.id.showFactButton);
showFactButton.setOnClickListener(this);
previousFactButton = findViewById(R.id.previousFactButton);
previousFactButton.setOnClickListener(this);
}
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.showFactButton:
String fact = factBook.getFact();
//update the screen with our new fact
factTextView.setText(fact);
int color = colorWheel.getColor();
relativeLayout.setBackgroundColor(color);
showFactButton.setTextColor(color);
break;
case R.id.previousFactButton:
fact = factBook.getPreviousFact();
factTextView.setText(fact);
color = colorWheel.getPreviousColor();
relativeLayout.setBackgroundColor(color);
previousFactButton.setTextColor(color);
break;
default:
break;
}
}
}
Code for Facts
class FactBook {
//Fields or Member Variables - Properties about the object
private final String[] facts = {
"Ants stretch when they wake up in the morning.",
"Ostriches can run faster than horses.",
"Olympic gold medals are actually made mostly of silver.",
"You are born with 300 bones; by the time you are an adult you will have 206.",
"It takes 8 minutes and 20 seconds for light from the Sun to reach Earth.",
"Some bamboo plants can grow almost a meter in just one day.",
"The state of Florida is bigger than England.",
"Some penguins can leap 2-3 meters out of the water.",
"On average, it takes 66 days to form a new habit.",
"Mammoths still walked the earth when the Great Pyramid was being built." };
// Methods - Actions the object can take
String getFact() {
//Randomly select a fact
Random randomGenerator = new Random();
int randomNumber = randomGenerator.nextInt(facts.length);
factNumbers.add(randomNumber);
return facts[randomNumber];
}
String getPreviousFact(){
//select the previous fact
int n = factNumbers.size();
n -= 1;
int x = factNumbers.get(n);
return facts[x];
}
}
Code for Colors
public class ColorWheel {
//Fields or Member Variables - Properties about the object
private final String[] colors = {
"#39add1", // light blue
"#3079ab", // dark blue
"#c25975", // mauve
"#e15258", // red
"#f9845b", // orange
"#838cc7", // lavender
"#7d669e", // purple
"#53bbb4", // aqua
"#51b46d", // green
"#e0ab18", // mustard
"#637a91", // dark gray
"#f092b0", // pink
"#b7c0c7", // light gray
"#03c4eb" // DanzerPress
};
// Methods - Actions the object can take
int getColor() {
//Randomly select a fact
Random randomGenerator = new Random();
int randomNumber = randomGenerator.nextInt(colors.length);
int color = Color.parseColor(colors[randomNumber]);
previousColors.add(color);
return color;
}
int getPreviousColor(){
//get previous fact color scheme
int n = previousColors.size();
n -= 1;
int prevColor = previousColors.get(n);
return prevColor;
}
}
1 Answer
Seth Kroger
56,413 PointsYou are on the right track with storing the previous color and fact, but I think you would do better to store each in their respective classes than in the Activity.