Dev-iL Dev-iL - 5 months ago 34
Android Question

Facebook SDK v4 LoginButton ignores XML customizations

The new Facebook SDK for Android (v4.0) that was released recently caused strange behavior for a customized LoginButton I'm using. Below is a comparison of how the same XML is rendered in different SDK versions.

The problem seems to be that the FB icon in SDK 4.x doesn't stretch properly to fit a custom-sized button, and at 4.0.1 the

android:layout_height
property is ignored altogether.

My question is how do I make the button appear in SDK 4.x like it did in SDK 3.x? Both XML and Java solutions are perfectly acceptable.

XML for SDK 3.x:

<com.facebook.widget.LoginButton
android:background="@color/com_facebook_blue"
android:id="@+id/login_btn_facebook"
android:layout_width="225dp"
android:layout_height="50dp"
android:layout_marginBottom="5dp"
android:layout_marginTop="5dp"
android:layout_gravity="center"
android:onClick="onFacebookLoginClick"
/>


How it looks on SDK 3.x (screenshot taken on a OnePlus One, running CM11S):
XML rendering when running with SDK v3.x

XML for SDK 4.x (the button's package was renamed + I had to change the width & font a bit to match the g+ button):

<com.facebook.login.widget.LoginButton
android:background="@color/com_facebook_blue"
android:id="@+id/login_btn_facebook"
android:layout_width="221dp"
android:layout_height="50dp"
android:layout_marginBottom="5dp"
android:layout_marginTop="5dp"
android:layout_gravity="center"
android:textSize="7pt"
android:onClick="onFacebookLoginClick"
/>


How it looks on SDK 4.0 (Screenshot taken on a Genymotion Nexus 5, running unmodified 4.4.4):
enter image description here

How it looks on SDK 4.0.1 (Same Genymotion Nexus 5):
enter image description here

Additional information




  1. Excerpt from the 4.0 -> 4.0.1 SDK change log:




Login button is updated to properly measure its size.



  1. Related posts:


  2. To support different screen sizes, above the login buttons I have a ViewPagerIndicator and a ViewPager that is configured to take up all available vertical space which remains after positioning elements with defined height.



Answer

I managed to get the desired result by following the following steps:

  1. Opened the Facebook SDK 3.x LoginButton code and saw how the button was styled there:

    this.setBackgroundResource(R.drawable.com_facebook_button_blue);
    this.setCompoundDrawablesWithIntrinsicBounds(
                 R.drawable.com_facebook_inverse_icon, 0, 0, 0);
    this.setCompoundDrawablePadding(getResources().getDimensionPixelSize(
                 R.dimen.com_facebook_loginview_compound_drawable_padding));
    this.setPadding(getResources().getDimensionPixelSize(
                    R.dimen.com_facebook_loginview_padding_left),
                getResources().getDimensionPixelSize(
                    R.dimen.com_facebook_loginview_padding_top),
                getResources().getDimensionPixelSize(
                    R.dimen.com_facebook_loginview_padding_right),
                getResources().getDimensionPixelSize(
                    R.dimen.com_facebook_loginview_padding_bottom));
    
  2. Based on the solution presented in this answer, I changed the button parameters during onPostCreate() as follows:

    float fbIconScale = 1.45F;
    Drawable drawable = hostActivity.getResources().getDrawable(
                                   com.facebook.R.drawable.com_facebook_button_icon);
    drawable.setBounds(0, 0, (int)(drawable.getIntrinsicWidth()*fbIconScale),
                             (int)(drawable.getIntrinsicHeight()*fbIconScale));
    authButton.setCompoundDrawables(drawable, null, null, null); 
    authButton.setCompoundDrawablePadding(hostActivity.getResources().
                      getDimensionPixelSize(R.dimen.fb_margin_override_textpadding));
    authButton.setPadding(
            hostActivity.getResources().getDimensionPixelSize(
                                                      R.dimen.fb_margin_override_lr),
            hostActivity.getResources().getDimensionPixelSize(
                                                     R.dimen.fb_margin_override_top),
            0,
            hostActivity.getResources().getDimensionPixelSize(
                                                 R.dimen.fb_margin_override_bottom));
    

    Where my custom dimensions are as follows:

    <dimen name="fb_margin_override_top">13dp</dimen>
    <dimen name="fb_margin_override_bottom">13dp</dimen>
    <!--The next value changes the margin between the FB icon and the left border:-->
    <dimen name="fb_margin_override_lr">10dp</dimen>
    <!--The next value changes the margin between the FB icon and the login text:-->
    <dimen name="fb_margin_override_textpadding">17dp</dimen>
    

This results in the desired layout:

The desired layout :D