Improve tab layout for older API levels

Increase minimum tab width.
Use fill gravity and fixed mode if required.

Author: pranavpandey

dynamic-support/src/main/java/com/pranavpandey/android/dynamic/support/fragment/DynamicViewPager2Fragment.java

@@ -76,7 +76,23 @@ public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceStat
 
         mViewPager.setOffscreenPageLimit(getItemCount());
         mViewPager.registerOnPageChangeCallback(
-                new DynamicOnPageChangeCallback(getChildFragmentManager()));
+                new DynamicOnPageChangeCallback(getChildFragmentManager()) {
+                    @Override
+                    public void onPageSelected(int position) {
+                        super.onPageSelected(position);
+
+                        Dynamic.setTextColor(getTabLayout());
+                    }
+
+                    @Override
+                    public void onPageScrollStateChanged(int state) {
+                        super.onPageScrollStateChanged(state);
+
+                        if (state == ViewPager2.SCROLL_STATE_IDLE) {
+                            Dynamic.setTextColor(getTabLayout());
+                        }
+                    }
+                });
         mViewPager.setAdapter(new ViewPagerAdapter(this, this));
         Dynamic.addHeader(getActivity(), R.layout.ads_tabs,
                 true, getSavedInstanceState() == null);

dynamic-support/src/main/java/com/pranavpandey/android/dynamic/support/fragment/DynamicViewPagerFragment.java

@@ -27,6 +27,7 @@
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentStatePagerAdapter;
 import androidx.viewpager.widget.ViewPager;
+import androidx.viewpager2.widget.ViewPager2;
 
 import com.google.android.material.tabs.TabLayout;
 import com.pranavpandey.android.dynamic.support.Dynamic;
@@ -75,7 +76,23 @@ public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceStat
 
         mViewPager.setOffscreenPageLimit(getItemCount());
         mViewPager.addOnPageChangeListener(
-                new DynamicOnPageChangeListener(getChildFragmentManager()));
+                new DynamicOnPageChangeListener(getChildFragmentManager()) {
+                    @Override
+                    public void onPageSelected(int position) {
+                        super.onPageSelected(position);
+
+                        Dynamic.setTextColor(getTabLayout());
+                    }
+
+                    @Override
+                    public void onPageScrollStateChanged(int state) {
+                        super.onPageScrollStateChanged(state);
+
+                        if (state == ViewPager2.SCROLL_STATE_IDLE) {
+                            Dynamic.setTextColor(getTabLayout());
+                        }
+                    }
+                });
         mViewPager.setAdapter(new ViewPagerAdapter(
                 getChildFragmentManager(), this));
         Dynamic.addHeader(getActivity(), R.layout.ads_tabs,
@@ -94,8 +111,9 @@ public void onAddActivityHeader(@Nullable View view) {
         if (getContext() == null || view == null) {
             return;
         }
-
+        
         mTabLayout = view.findViewById(R.id.ads_tab_layout);
+
         mTabLayout.setupWithViewPager(mViewPager);
     }
 

dynamic-support/src/main/java/com/pranavpandey/android/dynamic/support/widget/DynamicTabLayout.java

@@ -38,6 +38,7 @@
 import com.pranavpandey.android.dynamic.support.widget.base.DynamicTextWidget;
 import com.pranavpandey.android.dynamic.theme.Theme;
 import com.pranavpandey.android.dynamic.util.DynamicColorUtils;
+import com.pranavpandey.android.dynamic.util.DynamicSdkUtils;
 
 /**
  * A {@link TabLayout} to apply {@link DynamicTheme} according to the supplied parameters.
@@ -176,7 +177,6 @@ public void loadFromAttributes(@Nullable AttributeSet attrs) {
                     R.styleable.DynamicTabLayout_adt_contrast,
                     Theme.Contrast.AUTO);
 
-
             if (a.getBoolean(R.styleable.DynamicTabLayout_adt_dynamicCornerSize,
                     Defaults.ADS_DYNAMIC_CORNER_SIZE)) {
                 setSelectedTabIndicator(DynamicShapeUtils.getTabIndicatorRes(
@@ -187,6 +187,11 @@ public void loadFromAttributes(@Nullable AttributeSet attrs) {
         }
 
         initialize();
+
+        if (!DynamicSdkUtils.is19()) {
+            setTabGravity(GRAVITY_FILL);
+            setTabMode(MODE_FIXED);
+        }
     }
 
     @Override

dynamic-support/src/main/res/values-v19/dimens.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+	Copyright 2018-2022 Pranav Pandey
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+
+	   http://www.apache.org/licenses/LICENSE-2.0
+
+	Unless required by applicable law or agreed to in writing, software
+	distributed under the License is distributed on an "AS IS" BASIS,
+	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+	See the License for the specific language governing permissions and
+	limitations under the License.
+-->
+
+<resources>
+
+    <!-- Toolbar -->
+    <dimen name="ads_tab_min_width">48dp</dimen>
+
+</resources>

dynamic-support/src/main/res/values/dimens.xml

@@ -208,7 +208,7 @@
     <dimen name="ads_toolbar_margin_end_collapsing">@dimen/ads_page_horizontal_margin</dimen>
     <dimen name="ads_tab_inset_start">@dimen/ads_toolbar_inset_start_small</dimen>
     <dimen name="ads_tab_height">44dp</dimen>
-    <dimen name="ads_tab_min_width">48dp</dimen>
+    <dimen name="ads_tab_min_width">240dp</dimen>
     <dimen name="ads_tab_indicator_margin_vertical">0dp</dimen>
     <dimen name="ads_tab_indicator_margin_horizontal">@dimen/ads_margin_medium</dimen>
     <dimen name="ads_tab_indicator_height">3dp</dimen>