- Simple Refactoring: Creating a New Class 5:54
- Creating a New Class 2 objectives
- Simple Refactoring: Using a New Class 6:28
- Simple Refactoring 5 questions
- Dynamically Changing the Background Color 3:51
- Dynamically Changing the Background Color 1 objective
- Adding More Colors 3:43
- Using the New Colors 3:42
- Adding Colors 1 objective
- Adding an App Icon 4:50
- Adding an App Icon 3 questions
Preview
Video Player
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Using the New Colors
3:42Let's fix that error! In this video we'll fix a couple errors and then set the text color of our button.
Back in the ColorWheel class,
let's change getColor to return an int,
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instead of a string.
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And now we need to convert
the string color to an int.
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Right above the return statement,
let's add a new int variable named color.
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And let's set it equal to
Color with a capital C, dot.
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And then if we start typing parseColor, we
can see that parseColor is a method that
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takes in a colorString and returns an int,
just what we're looking for.
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Hit Enter to select it and
add a semicolon.
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The parseColor method is a handy utility
method that takes a hexadecimal string,
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just like we have up here, and
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converts it to an integer representation
that Android can understand.
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So instead of returning
a randomly selected color string,
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let's pass that random color
string into the parseColor method.
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Finally, since we need to
be returning an integer,
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let's return our new color variable and
head back to fun facts activity.
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Now, instead of a string,
we're returning an int.
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So color should be an int, not a string.
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Looks good, now let's run our app and
verify it's working as we expect it to.
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Okay, moment of truth, tap the button,
and nice, all sorts of different colors.
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There's one more thing I'd like
to do here, one last color.
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Notice that the color of
the button text is black, but
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in our mock ups,
it's matching the background color.
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Let's go back to our code and change this.
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In the onClick method,
we already have the color we want to use.
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And we already have a variable for
our button, showFactButton.
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Let's add a new line at the bottom of
onClick and add a reference to our button.
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Now let's look for the method we need.
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Let's type .set and
we're looking for text color.
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So let's add text, and then down here,
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we see a method called setTextColor
that takes on an int parameter.
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Let's pick that one.
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Then let's pass in our color variable.
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And cool, but we're not quite done.
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We're only changing the text color
after the button has been tapped.
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If the button hasn't been tapped,
we'll still see black text.
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We should change our button's default
text color to match the default
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background, green.
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Let's go back into our
activity_fun_facts layout file.
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And make sure we're on the Design tab.
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Then let's select our relativeLayout.
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And copy the green color from
the background property.
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Then let's select our button,
scroll down to the textColor property.
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Paste in our color, hit Enter,
and there we go, green text.
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Now let's run the app to
make sure everything works.
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Okay, just like we expected,
lots of different colors for
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the background and lots of different
colors for our button text.
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All right, that's really coming together.
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We're done with all the programming, but
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there's still one little thing before we
can move on to testing and debugging.
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