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syimo/LoopingAdapter

Created November 18, 2024 08:56
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Save syimo/5b0e7fc9220ae1eb0f94924166e008a2 to your computer and use it in GitHub Desktop.
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recyclerview with bottom seekbar
Raw
activity_main
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:layout_marginTop="100dp"
android:background="@color/cardview_shadow_start_color"
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" />
<SeekBar
android:id="@+id/seekBar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp" />
</LinearLayout>
Raw
LoopingAdapter
public class LoopingAdapter extends RecyclerView.Adapter<LoopingAdapter.ViewHolder> {
private List<String> data;
public LoopingAdapter(List<String> data) {
this.data = data;
}
@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.simple_text, parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
// 利用 position 进行循环映射
String text = data.get(position % data.size());
holder.textView.setText(text);
}
@Override
public int getItemCount() {
// 设置一个很大的值来模拟无限循环
return Integer.MAX_VALUE;
}
class ViewHolder extends RecyclerView.ViewHolder {
TextView textView;
ViewHolder(View itemView) {
super(itemView);
textView = itemView.findViewById(R.id.tv);
}
}
}
Raw
MainActivity
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
enableEdgeToEdge()
setContentView(R.layout.activity_main)
// ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main)) { v, insets ->
// val systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars())
// v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom)
// insets
// }
val recyclerView = findViewById<RecyclerView>(R.id.recyclerView)
val seekBar = findViewById<SeekBar>(R.id.seekBar)
// 准备 12 个数据
val data: MutableList<String> = ArrayList()
for (i in 1..50) {
data.add("Item $i")
}
// 设置 Adapter
val adapter = LoopingAdapter(data)
recyclerView.adapter = adapter
// 设置 SnapHelper
// val snapHelper = LinearSnapHelper()
// snapHelper.attachToRecyclerView(recyclerView)
// 设置横向 LinearLayoutManager
val layoutManager = LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false)
recyclerView.layoutManager = layoutManager
// 设置起始位置
val startPosition = Int.MAX_VALUE / 2 - (Int.MAX_VALUE / 2 % data.size)
recyclerView.scrollToPosition(startPosition)
Log.e("asdasdasdas", "stat===" + startPosition)
// 添加滚动监听，对齐到第一个可见项目
recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
super.onScrollStateChanged(recyclerView, newState)
if (newState == RecyclerView.SCROLL_STATE_IDLE) { // 滑动停止
val layoutManager = recyclerView.layoutManager as LinearLayoutManager?
layoutManager?.let {
val firstVisiblePosition = it.findFirstVisibleItemPosition()
val firstVisibleView = it.findViewByPosition(firstVisiblePosition)
firstVisibleView?.let { view ->
val offset = view.left // 计算偏移量
if (offset != 0) { // 仅当未对齐时才滑动
recyclerView.smoothScrollBy(offset, 0)
}
}
}
}
}
})
// 设置 SeekBar 最大值为数据量
seekBar.max = data.size - 1
// 监听 RecyclerView 滚动
recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
super.onScrolled(recyclerView, dx, dy)
val firstVisibleItem = layoutManager.findFirstVisibleItemPosition() % data.size
seekBar.progress = firstVisibleItem
Log.e("asdasdasdas", "stat===" + firstVisibleItem)
}
})
}
}
Raw
simple_text
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:id="@+id/tv"
android:text="asdsaddasda"
android:layout_width="150dp"
android:background="@android:color/holo_blue_light"
android:layout_marginEnd="10dp"
android:layout_height="50dp">
</TextView>
</FrameLayout>
@syimo
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syimo commented Nov 18, 2024 

<ProgressBar
    android:id="@+id/seekBar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:progress="0"
    android:max="12"
    android:padding="16dp"
    android:indeterminate="false"
    style="?android:attr/progressBarStyleHorizontal" />

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