Saturday, April 9, 2011

Using Custom fonts on Android

I had to do this for a project that I am working on, and I felt that it wasn't possible to achieve this. Well, there are several examples on the internet regarding this and nothing seemed to be working for me. So, in this post, we will see how to use custom fonts for your application on Android.

Few things before we start off:
  • Not all fonts are compatible with Android
  • You need to package the ttf files with your apk
  • It's obviously a little bit of extra work
So for this example, we have a TextView and a Button with different fonts. To be able to use your custom font everywhere, ie, on all the TextView and Button widgets in your app, you will have to extend these classes to create your own TextView and Button classes. I have named them as MyTextView and MyButton. And then, I can use these buttons in my layout xml files, with the fully-qualified name of my custom classes.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=""
    android:orientation="vertical" android:layout_width="fill_parent"
        android:layout_marginTop="10dip" android:id="@+id/textView"
        android:layout_width="fill_parent" android:layout_height="wrap_content"
        android:text="@string/hello" android:textSize="20sp"></com.beanie.samples.customfont.MyTextView>

        android:layout_marginTop="10dip" android:id="@+id/textView"
        android:layout_width="fill_parent" android:layout_height="wrap_content"
        android:text="@string/hello" android:textSize="20sp"></com.beanie.samples.customfont.MyButton>
In both these classes, we have a method called init() which is called from all the constructors. The method is just 3 line long.
        if (!isInEditMode()) {
                  Typeface tf = Typeface.createFromAsset(getContext().getAssets(), "fonts/ds_digib.ttf");
Simple!!! You might notice that there is an if condition. This is not required, but it does help when you are preparing your layouts on eclipse, and you need to keep checking if everything's fine. This method, isInEditMode() returns true while eclipses tries to render the view from the XML.

This is what the documentation says:
Indicates whether this View is currently in edit mode. A View is usually in edit mode when displayed within a developer tool. For instance, if this View is being drawn by a visual user interface builder, this method should return true. Subclasses should check the return value of this method to provide different behaviors if their normal behavior might interfere with the host environment. For instance: the class spawns a thread in its constructor, the drawing code relies on device-specific features, etc. This method is usually checked in the drawing code of custom widgets.
If you don't put this condition, the layout editor will complain about not being able to set the TypeFace. So, in the layout editor, you will see your TextView and Button widgets with the default font. But, when you run your app on an emulator or a device, you can see the goodness of your custom fonts.

The source code for the sample project can be found here. You can find 3 different fonts (ttf file) in the assets folder to play with.

Monday, April 4, 2011

Inverted Android Button

Nothing complex. Just a few lines of code to invert your button. A horizontal flip of 180 degrees is pretty simple to achieve. If you want it with a specific angle, it might be a bit tricky.

Lets start with a creating a custom button class that extends the android Button class. Name it as

You will need to override it's onDraw() method to rotate the canvas, so that before any drawing is done, you rotate it by 180 degrees. To make the text-alignment perfect, you will also need to do a few calculations.
    protected void onDraw(Canvas canvas) {
        int left = getPaddingLeft();
        int top = getPaddingTop();
        int right = getPaddingRight();
        int bottom = getPaddingBottom();
        int width = getWidth() - left - right;
        int height = getHeight() - top - bottom;
        int saveCount = canvas.getSaveCount();
        canvas.translate(left + width / 2, top + height / 2);
        canvas.translate((-width / 2)-left, (-height / 2)-top);

There you go. You can now add this button anywhere in your XML layouts and you will always get an inverted button.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=""
    android:orientation="vertical" android:layout_width="fill_parent"
    <Button android:text="Button" android:id="@+id/button1"
        android:layout_width="wrap_content" android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal|top" android:textStyle="bold"></Button>
        android:text="Button" android:id="@+id/button2" android:layout_width="wrap_content"
        android:layout_height="wrap_content" android:layout_gravity="center_horizontal|bottom"

You can find the source code here. Happy coding!!!!