有什么方法可以将渐变而不是颜色应用于Android中的TabLayout指示器?如果没有直接的方法可以做到这一点,那么有什么技巧甚至库可以实现吗?
<android.support.design.widget.TabLayout
android:id="@+id/tabLayout"
android:layout_width="match_parent"
android:layout_height="60dp"
android:background="@android:color/white"
app:layout_constraintBottom_toBottomOf="parent"
app:tabIndicator="@drawable/drawable_shape_home_tab_indicator"
app:tabIndicatorColor="@color/colorGradiantEnd"
app:tabIndicatorFullWidth="true"
app:tabIndicatorGravity="top">
<android.support.design.widget.TabItem
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:icon="@drawable/drawable_selector_home_tab_dashboard" />
<android.support.design.widget.TabItem
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:icon="@drawable/drawable_selector_home_tab_surveys" />
</android.support.design.widget.TabLayout>
答案 0 :(得分:2)
您可以创建一个自定义视图,并在TabLayout的顶部绘制渐变作为指标。就我而言,我使用视图寻呼机来获取滚动值以动画化指示器的运动。这是我编写的article中的代码段。
TabLayout mTabs;
View mIndicator;
ViewPager mViewPager;
private int indicatorWidth;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//..
//Assign view references and set up view pager
//..
mViewPager.setAdapter(adapter);
mTabs.setupWithViewPager(mViewPager);
//Determine indicator width at runtime
mTabs.post(new Runnable() {
@Override
public void run() {
indicatorWidth = mTabs.getWidth() / mTabs.getTabCount();
//Assign new width
FrameLayout.LayoutParams indicatorParams = (FrameLayout.LayoutParams) mIndicator.getLayoutParams();
indicatorParams.width = indicatorWidth;
mIndicator.setLayoutParams(indicatorParams);
}
});
mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
//To move the indicator as the user scroll, we will need the scroll offset values
//positionOffset is a value from [0..1] which represents how far the page has been scrolled
//see https://developer.android.com/reference/android/support/v4/view/ViewPager.OnPageChangeListener
@Override
public void onPageScrolled(int i, float positionOffset, int positionOffsetPx) {
FrameLayout.LayoutParams params = (FrameLayout.LayoutParams)mIndicator.getLayoutParams();
//Multiply positionOffset with indicatorWidth to get translation
float translationOffset = (positionOffset+i) * indicatorWidth ;
params.leftMargin = (int) translationOffset;
mIndicator.setLayoutParams(params);
}
@Override
public void onPageSelected(int i) {
}
@Override
public void onPageScrollStateChanged(int i) {
}
});
}