尝试使头像pic变小，直到使用OnOffsetChanged消失，但它在片段中不起作用。我用同样的方式尝试了它的工作。
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white"
android:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:id="@+id/app_bar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleTextAppearance="@style/TextAppearance.AppCompat.Title"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:titleEnabled="false">
<ImageView
android:layout_width="match_parent"
android:layout_height="220dp"
android:fitsSystemWindows="true"
android:scaleType="centerCrop"
android:src="@drawable/bg_polygon"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:contentInsetStartWithNavigation="0dp"
app:layout_collapseMode="pin"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView>
**some code**
</android.support.v4.widget.NestedScrollView>
<com.mikhaellopez.circularimageview.CircularImageView
android:id="@+id/profileImage"
android:layout_width="100dp"
android:layout_height="100dp"
android:src="@drawable/photo_female_6"
app:civ_border="true"
app:civ_border_width="2dp"
app:layout_anchor="@id/app_bar_layout"
app:layout_anchorGravity="bottom|center" />
我尝试使用OnOffsetChangedListener两种方式使用AppBarLayout) v.findViewById(R.id.app_bar_layout)).addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener())
第一个是调用（public class ProfileFragment extends Fragment implements
AppBarLayout.OnOffsetChangedListener {
public ProfileFragment() {
// Required empty public constructor
}
public static ProfileFragment newInstance() {
ProfileFragment fragment = new ProfileFragment();
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
AppBarLayout appBarLayout = (AppBarLayout) getActivity().findViewById(R.id.app_bar_layout);
}
@Override
public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_profile, container, false);
return inflater.inflate(R.layout.fragment_profile, container, false);
}
private void initComponent(View v) {
final CircularImageView image = v.findViewById(R.id.profileImage);
final CollapsingToolbarLayout collapsing_toolbar = v.findViewById(R.id.collapsing_toolbar);
((AppBarLayout) v.findViewById(R.id.app_bar_layout)).addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
@Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
int min_height = ViewCompat.getMinimumHeight(collapsing_toolbar) * 2;
float scale = (float) (min_height + verticalOffset) / min_height;
image.setScaleX(scale >= 0 ? scale : 0);
image.setScaleY(scale >= 0 ? scale : 0);
}
});
}
@Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
final CircularImageView image;
image = (CircularImageView) getActivity().findViewById(R.id.profileImage);
final CollapsingToolbarLayout collapsing_toolbar = (CollapsingToolbarLayout) getActivity().findViewById(R.id.collapsing_toolbar);
int min_height = ViewCompat.getMinimumHeight(collapsing_toolbar) * 2;
float scale = (float) (min_height + verticalOffset) / min_height;
image.setScaleX(scale >= 0 ? scale : 0);
image.setScaleY(scale >= 0 ? scale : 0);
}
}
来覆盖方法
第二个是在fragmet类中实现appbarlayout
CollapsingToolbarLayout当我调试代码时，我发现即使我使用join也没有调用该方法。
答案 0 :(得分：1)
我通过添加“onactivitycreated”方法解决了这个问题，所以当我试图获取视图时我会存在
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
AppBarLayout mAppBarLayout = getView().findViewById(R.id.app_bar_layout);
final CollapsingToolbarLayout collapsing_toolbar = getView().findViewById(R.id.collapsing_toolbar);
final CircularImageView image = getView().findViewById(R.id.profileImage);
mAppBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
@Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
int min_height = ViewCompat.getMinimumHeight(collapsing_toolbar) * 2;
float scale = (float) (min_height + verticalOffset) / min_height;
image.setScaleX(scale >= 0 ? scale : 0);
image.setScaleY(scale >= 0 ? scale : 0);
}
});AppBarLayout mAppBarLayout = getView().findViewById(R.id.app_bar_layout);
final CollapsingToolbarLayout collapsing_toolbar = getView().findViewById(R.id.collapsing_toolbar);
final CircularImageView image = getView().findViewById(R.id.profileImage);
mAppBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
@Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
int min_height = ViewCompat.getMinimumHeight(collapsing_toolbar) * 2;
float scale = (float) (min_height + verticalOffset) / min_height;
image.setScaleX(scale >= 0 ? scale : 0);
image.setScaleY(scale >= 0 ? scale : 0);
}
});
}