我正在尝试构建一个RecyclerView
,根据他们与屏幕中心的距离来设置项目,例如设置菜单,跟随官方“Android开发者”的this tutorial。
喜欢这张图片:
问题是updateChild()
方法永远不会被调用。我尝试使用断点来检查我的偏移助手是否实际设置了,并且在updateChild中还有一个,但是一切都设置正确但不起作用。
这是我的代码:
穿/的build.gradle
compile 'com.google.android.support:wearable:2.0.0'
compile 'com.google.android.gms:play-services-wearable:10.2.0'
provided 'com.google.android.wearable:wearable:2.0.0'
MainActivity.java
mRecyclerView = (WearableRecyclerView) findViewById(R.id.recycler);
mLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
mAdapter = new MainAdapter(this, null);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
mRecyclerView.setCenterEdgeItems(true);
mRecyclerView.setOffsettingHelper(new RecyclerOffsettingHelper());
RecyclerOffsettingHelper.java
public class RecyclerOffsettingHelper extends DefaultOffsettingHelper {
/** How much should we scale the icon at most. */
private static final float MAX_ICON_PROGRESS = 0.65f;
private float mProgressToCenter;
public RecyclerOffsettingHelper() {}
@Override
public void updateChild(View child, WearableRecyclerView parent) {
super.updateChild(child, parent);
// Figure out % progress from top to bottom
float centerOffset = ((float) child.getHeight() / 2.0f) / (float) parent.getHeight();
float yRelativeToCenterOffset = (child.getY() / parent.getHeight()) + centerOffset;
// Normalize for center
mProgressToCenter = Math.abs(0.5f - yRelativeToCenterOffset);
// Adjust to the maximum scale
mProgressToCenter = Math.min(mProgressToCenter, MAX_ICON_PROGRESS);
child.setScaleX(1 - mProgressToCenter);
child.setScaleY(1 - mProgressToCenter);
}
}
我有什么错过教程或做错了吗? 提前谢谢。
答案 0 :(得分:0)
我反编译了WearableRecyclerView
类,奇怪地发现没有使用mOffsettingHelper
方法设置的setOffsettingHeler()
实例,除了名为OffsettingLinearLayoutManager
的私有类扩展LinearLayoutManager
并将严格设置为Constructor方法上的recycleler视图。因此,如果您在代码中设置了自己的布局管理器,则OffsettingHelper将无法使用。
所以我想出了一个解决方法并创建了我自己的布局管理器来覆盖scrollVerticallyBy
和onLayoutChildren
方法,以便在updateChide
对象上调用mOffettingHelper
。
以下是我的自定义LayoutManager
的工作代码:
public class OffsettingLinearLayoutManager extends LinearLayoutManager {
private WearableRecyclerView mWearableRecyclerView;
public OffsettingLinearLayoutManager(Context context) {
super(context);
}
public OffsettingLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
super(context, orientation, reverseLayout);
}
public OffsettingLinearLayoutManager(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
}
public void attachRecyclerView(WearableRecyclerView wearableRecyclerView) {
this.mWearableRecyclerView = wearableRecyclerView;
}
public void detachRecyclerView() {
this.mWearableRecyclerView = null;
}
public int scrollVerticallyBy(int dy, RecyclerView.Recycler recycler, RecyclerView.State state) {
int scrolled = super.scrollVerticallyBy(dy, recycler, state);
this.updateLayout();
return scrolled;
}
public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {
super.onLayoutChildren(recycler, state);
if(this.getChildCount() != 0) {
this.updateLayout();
}
}
private void updateLayout() {
if(mWearableRecyclerView != null && mWearableRecyclerView.getOffsettingHelper() != null) {
for(int count = 0; count < this.getChildCount(); ++count) {
View child = this.getChildAt(count);
mWearableRecyclerView.getOffsettingHelper().updateChild(child, mWearableRecyclerView);
}
}
}
}
注意:不要忘记使用attachRecyclerView
方法设置WearableRecyclerView
个实例。
希望它对某人有帮助。