我在导航抽屉里面使用了recyclelerView,我正在使用这个库Twoway-view获得点击和选择支持。
它完美无缺,我可以在每个位置的OnClick方法中更改文本和图标的颜色而没有问题:
itemClickSupport.setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
@Override
public void onItemClick(RecyclerView parent, View view, int position, long id) {
TypedValue typedValue = new TypedValue();
MainActivity.this.getTheme().resolveAttribute(R.attr.colorAccent, typedValue, true);
final int color = typedValue.data;
//TODO Icon and text colors
for (int i = 0; i < drawerTitles.length; i++){
if (i == position){
ImageView imageViewDrawerIcon = (ImageView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.imageViewDrawerIcon);
TextView textViewDrawerTitle = (TextView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.textViewDrawerItemTitle);
imageViewDrawerIcon.setColorFilter(color);
if(Build.VERSION.SDK_INT > 15){
imageViewDrawerIcon.setImageAlpha(255);
}else{
imageViewDrawerIcon.setAlpha(255);
}
textViewDrawerTitle.setTextColor(color);
RelativeLayout relativeLayoutDrawerItem = (RelativeLayout) recyclerViewDrawer.getChildAt(i).findViewById(R.id.relativeLayoutDrawerItem);
relativeLayoutDrawerItem.setFocusableInTouchMode(true);
}else{
ImageView imageViewDrawerIcon = (ImageView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.imageViewDrawerIcon);
TextView textViewDrawerTitle = (TextView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.textViewDrawerItemTitle);
imageViewDrawerIcon.setColorFilter(getResources().getColor(R.color.md_text));
if(Build.VERSION.SDK_INT > 15){
imageViewDrawerIcon.setImageAlpha(138);
}else{
imageViewDrawerIcon.setAlpha(138);
}
textViewDrawerTitle.setTextColor(getResources().getColor(R.color.md_text));
RelativeLayout relativeLayoutDrawerItem = (RelativeLayout) recyclerViewDrawer.getChildAt(i).findViewById(R.id.relativeLayoutDrawerItem);
relativeLayoutDrawerItem.setFocusableInTouchMode(false);
}
}
//TODO Fragments (closedrawers before setfragment)
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
@Override
public void run() {
// Do something after some time
}
}, 250);
mDrawerLayout.closeDrawers();
}
});
问题是我想要访问该方法中的第一个项目,但在它之前(设置选择的第一个项目,使用不同的颜色等)。
但是当我尝试在OnClick方法之外获取第一个项目时,我得到了崩溃(空引用):
ImageView imageViewDrawerIcon = (ImageView) recyclerViewDrawer.getChildAt(0).findViewById(R.id.imageViewDrawerIcon);
所有代码:
// Setup RecyclerView inside drawer
recyclerViewDrawer = (RecyclerView) findViewById(R.id.recyclerViewDrawer);
recyclerViewDrawer.setHasFixedSize(true);
recyclerViewDrawer.setLayoutManager(new LinearLayoutManager(MainActivity.this));
ArrayList<DrawerItem> drawerItems = new ArrayList<>();
final String[] drawerTitles = getResources().getStringArray(R.array.drawer);
final TypedArray drawerIcons = getResources().obtainTypedArray(R.array.drawerIcons);
for (int i = 0; i < drawerTitles.length; i++) {
drawerItems.add(new DrawerItem(drawerTitles[i], drawerIcons.getDrawable(i)));
}
drawerIcons.recycle();
adapterDrawer = new DrawerAdapter(drawerItems);
recyclerViewDrawer.setAdapter(adapterDrawer);
// Here is the problem
ImageView imageViewDrawerIcon2 = (ImageView) recyclerViewDrawer.getChildAt(0).findViewById(R.id.imageViewDrawerIcon);
// RecyclerView item listener.
ItemClickSupport itemClickSupport = ItemClickSupport.addTo(recyclerViewDrawer);
itemClickSupport.setOnItemClickListener(new ItemClickSupport.OnItemClickListener() {
@Override
public void onItemClick(RecyclerView parent, View view, int position, long id) {
TypedValue typedValue = new TypedValue();
MainActivity.this.getTheme().resolveAttribute(R.attr.colorAccent, typedValue, true);
final int color = typedValue.data;
//TODO Icon and text colors
for (int i = 0; i < drawerTitles.length; i++){
if (i == position){
ImageView imageViewDrawerIcon = (ImageView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.imageViewDrawerIcon);
TextView textViewDrawerTitle = (TextView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.textViewDrawerItemTitle);
imageViewDrawerIcon.setColorFilter(color);
if(Build.VERSION.SDK_INT > 15){
imageViewDrawerIcon.setImageAlpha(255);
}else{
imageViewDrawerIcon.setAlpha(255);
}
textViewDrawerTitle.setTextColor(color);
RelativeLayout relativeLayoutDrawerItem = (RelativeLayout) recyclerViewDrawer.getChildAt(i).findViewById(R.id.relativeLayoutDrawerItem);
relativeLayoutDrawerItem.setFocusableInTouchMode(true);
}else{
ImageView imageViewDrawerIcon = (ImageView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.imageViewDrawerIcon);
TextView textViewDrawerTitle = (TextView) recyclerViewDrawer.getChildAt(i).findViewById(R.id.textViewDrawerItemTitle);
imageViewDrawerIcon.setColorFilter(getResources().getColor(R.color.md_text));
if(Build.VERSION.SDK_INT > 15){
imageViewDrawerIcon.setImageAlpha(138);
}else{
imageViewDrawerIcon.setAlpha(138);
}
textViewDrawerTitle.setTextColor(getResources().getColor(R.color.md_text));
RelativeLayout relativeLayoutDrawerItem = (RelativeLayout) recyclerViewDrawer.getChildAt(i).findViewById(R.id.relativeLayoutDrawerItem);
relativeLayoutDrawerItem.setFocusableInTouchMode(false);
}
}
//TODO Fragments (closedrawers before setfragment)
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
@Override
public void run() {
// Do something after some time
}
}, 250);
mDrawerLayout.closeDrawers();
}
});
答案 0 :(得分:11)
就我而言,它就像魅力一样工作
View viewItem = recycleView.getLayoutManager().findViewByPosition(position);
View icon = viewItem.findViewById(R.id.view);
答案 1 :(得分:8)
我最终解决了这个问题(source):
recyclerViewDrawer.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
ImageView imageViewDrawerIcon = (ImageView) recyclerViewDrawer.getChildAt(0).findViewById(R.id.imageViewDrawerIcon);
TextView textViewDrawerTitle = (TextView) recyclerViewDrawer.getChildAt(0).findViewById(R.id.textViewDrawerItemTitle);
imageViewDrawerIcon.setColorFilter(color);
if (Build.VERSION.SDK_INT > 15) {
imageViewDrawerIcon.setImageAlpha(255);
} else {
imageViewDrawerIcon.setAlpha(255);
}
textViewDrawerTitle.setTextColor(color);
RelativeLayout relativeLayoutDrawerItem = (RelativeLayout) recyclerViewDrawer.getChildAt(0).findViewById(R.id.relativeLayoutDrawerItem);
relativeLayoutDrawerItem.setFocusableInTouchMode(true);
// unregister listener (this is important)
recyclerViewDrawer.getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
});
顺便说一句,如果有人有更好的解决方案,我想知道。
答案 2 :(得分:4)
我会使用findViewHolderForAdapterPosition()或findViewByPosition()来查找该索引的根视图。但是,确保加载数据的方式取决于您。
答案 3 :(得分:3)
这对我有用。
recyclerView.post(new Runnable() {
@Override
public void run() {
View viewItem = recycleView.getLayoutManager().findViewByPosition(position);
View icon = viewItem.findViewById(R.id.view);
}
});
答案 4 :(得分:0)
findViewByPosition
是LayoutManager
的一种方法,适用于所有LayoutManager。
因此您可以使用recycleView.getLayoutManager()
和findViewByPosition(pos)
。
recyclerView.findViewHolderForAdapterPosition(pos)
也可以工作。