TabLayout有两个模式scrollable和fixed
scrollable:tab个数过多自动滚动
缺点:当tab数量比较少时所有tab宽度无法占满
fixed:不滚动平均分配所有tab
缺点:当tab数量过多tab被无限压缩,很难看
想过用第三方库解决,找了个SmartTab,能解决,但又出现了其他问题,不能更新指定tab的title
解决方法:重写TabLayout的addTab(@NonNull Tab tab, int position, boolean setSelected)方法
查看源码发现Tab.class中有一个字段TabView mView,其实mView就是每个tab的主布局
而TabView继承自LinearLayout,这就好办了,在添加tab时动点手脚,利用反射取出mView,强转为LinearLayout,设置其权重为1即可
这是我修改后的TabLayout
xml
<MyTabLayout
android:id="@+id/tab_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="scrollable"
app:tabTextColor="@color/darkgreen"/>
java
import android.content.Context;
import android.support.annotation.NonNull;
import android.support.design.widget.TabLayout;
import android.util.AttributeSet;
import android.widget.LinearLayout;
import java.lang.reflect.Field;
public class MyTabLayout extends TabLayout
{
public MyTabLayout(Context context)
{
super(context);
}
public MyTabLayout(Context context, AttributeSet attrs)
{
super(context, attrs);
}
public MyTabLayout(Context context, AttributeSet attrs, int defStyleAttr)
{
super(context, attrs, defStyleAttr);
}
@Override
public void addTab(@NonNull Tab tab, int position, boolean setSelected)
{
super.addTab(tab, position, setSelected);
setTab(tab);
}
void setTab(Tab tab)
{
try
{
Field mViewF = Tab.class.getDeclaredField("mView");
mViewF.setAccessible(true);
LinearLayout mView = (LinearLayout) mViewF.get(tab);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
layoutParams.weight = 1;
mView.setLayoutParams(layoutParams);
} catch (NoSuchFieldException e)
{
e.printStackTrace();
} catch (IllegalAccessException e)
{
e.printStackTrace();
}
}
}