Android 写排行榜，顶部前三

activity_step_rank.xml

<?xml version="1.0" encoding="UTF-8"?>
<FrameLayout android:layout_height="match_parent" android:layout_width="match_parent" android:id="@+id/fragment_parent" android:orientation="vertical" xmlns:android="http://schemas.android.com/apk/res/android"> </FrameLayout>

fragment_step_rank.xml

<?xml version="1.0" encoding="UTF-8"?>-<LinearLayout android:layout_height="match_parent" android:layout_width="match_parent" android:orientation="vertical" xmlns:android="http://schemas.android.com/apk/res/android"><androidx.recyclerview.widget.RecyclerView android:layout_height="match_parent" android:layout_width="match_parent" android:id="@+id/recycler_view"/></LinearLayout>

item_step_rank.xml

<?xml version="1.0" encoding="UTF-8"?>-<LinearLayout android:layout_height="60dp" android:layout_marginBottom="6dp" android:layout_width="match_parent" android:orientation="horizontal" xmlns:android="http://schemas.android.com/apk/res/android"><TextView android:layout_height="wrap_content" android:layout_width="wrap_content" android:textSize="20sp" android:textColor="#333333" android:layout_gravity="center_vertical" android:paddingRight="12dp" android:paddingLeft="12dp" android:id="@+id/tv_rank"/><View android:layout_height="match_parent" android:layout_width="match_parent" android:background="#EDEDED"/></LinearLayout>

item_step_rank_top.xml

<?xml version="1.0" encoding="UTF-8"?>-<LinearLayout android:orientation="horizontal" android:layout_height="200dp" android:layout_width="match_parent" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:android="http://schemas.android.com/apk/res/android"><!--第二名-->-<androidx.constraintlayout.widget.ConstraintLayout android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="1"><View android:layout_height="80dp" android:layout_width="80dp" app:layout_constraintTop_toTopOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintBottom_toBottomOf="parent" android:background="#EDEDED"/></androidx.constraintlayout.widget.ConstraintLayout><!--第一名-->-<androidx.constraintlayout.widget.ConstraintLayout android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="1"><View android:layout_height="80dp" android:layout_width="80dp" app:layout_constraintTop_toTopOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintBottom_toBottomOf="parent" android:background="#EDEDED"/></androidx.constraintlayout.widget.ConstraintLayout><!--第三名-->-<androidx.constraintlayout.widget.ConstraintLayout android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="1"><View android:layout_height="80dp" android:layout_width="80dp" app:layout_constraintTop_toTopOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintBottom_toBottomOf="parent" android:background="#EDEDED"/></androidx.constraintlayout.widget.ConstraintLayout></LinearLayout>

BaseHolder.java

package com.example.myapplication2024.rank;import android.content.Context;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.GradientDrawable;
import android.util.SparseArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;import androidx.annotation.ColorRes;
import androidx.annotation.DrawableRes;
import androidx.annotation.IdRes;
import androidx.annotation.LayoutRes;
import androidx.annotation.NonNull;
import androidx.collection.ArrayMap;
import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.RecyclerView;/*** RecyclerView ViewHolder*/
public class BaseHolder extends RecyclerView.ViewHolder {private final Context mContext;private final SparseArray<View> mSparseArray;public BaseHolder(@NonNull View itemView) {super(itemView);mContext = itemView.getContext();mSparseArray = new SparseArray<>();}public BaseHolder(@LayoutRes int resource, @NonNull ViewGroup parent) {this(LayoutInflater.from(parent.getContext()).inflate(resource, parent, false));}/*** 设置 itemView最小高度*/public BaseHolder setMinHeight(int minHeight) {itemView.setMinimumHeight(minHeight);return this;}public Context getContext() {return mContext;}@SuppressWarnings("all")public <T extends View> T findViewById(@IdRes int id) {View view = mSparseArray.get(id);if (view == null) {view = itemView.findViewById(id);mSparseArray.put(id, view);}return ((T) view);}public <T extends View> T findViewById(@IdRes int id, boolean visibility) {T view = findViewById(id);view.setVisibility(visibility ? View.VISIBLE : View.GONE);return view;}public <T extends View> T findViewById(@IdRes int id, int visibility) {T view = findViewById(id);view.setVisibility(visibility);return view;}public void setText(@IdRes int id, CharSequence text) {TextView textView = findViewById(id);textView.setText(text);}public void setText(@IdRes int id, int textResOrNum) {TextView textView = findViewById(id);try {textView.setText(getContext().getString(textResOrNum));} catch (Exception e) {textView.setText(String.valueOf(textResOrNum));}}public void setHint(@IdRes int id, CharSequence text) {TextView textView = findViewById(id);textView.setHint(text);}public void setHint(@IdRes int id, int textResOrNum) {TextView textView = findViewById(id);try {textView.setHint(getContext().getString(textResOrNum));} catch (Exception e) {textView.setHint(String.valueOf(textResOrNum));}}public ImageView findImageById(@IdRes int imageViewId) {return findViewById(imageViewId);}public ImageView findImageById(@IdRes int imageViewId, boolean visibility) {return findViewById(imageViewId, visibility);}public ImageView findImageById(@IdRes int imageViewId, int visibility) {return findViewById(imageViewId, visibility);}public void setVisibility(int id, int visibility) {findViewById(id).setVisibility(visibility);}public void setVisibility(int id, boolean visibility) {findViewById(id).setVisibility(visibility ? View.VISIBLE : View.GONE);}public void setImageResource(@IdRes int imageViewId, @DrawableRes int drawableRes) {ImageView imageView = findViewById(imageViewId);imageView.setImageResource(drawableRes);}private final ArrayMap<String, Drawable> mCircleDrawableMap = new ArrayMap<>();/*** 获取圆形的Drawable** @param size  宽高* @param color 颜色*/public Drawable getCircleDrawable(int size, int color) {String key = String.valueOf(size) + color;Drawable drawable = mCircleDrawableMap.get(key);if (drawable == null) {GradientDrawable gradientDrawable = new GradientDrawable();gradientDrawable.setShape(GradientDrawable.OVAL);if (size > 0) {gradientDrawable.setSize(size, size);}gradientDrawable.setColor(color);drawable = gradientDrawable;mCircleDrawableMap.put(key, drawable);}return drawable;}public Drawable getCircleDrawable(int size) {return getCircleDrawable(size, Color.parseColor("#EDEDED"));}public int getColor(@ColorRes int id) {return ContextCompat.getColor(getContext(), id);}}

StepRank.java

package com.example.myapplication2024.rank;/*** 步数数据*/
public class StepRank {
}

StepRankActivity.java

package com.example.myapplication2024.rank;import android.content.Context;
import android.content.Intent;
import android.os.Bundle;import com.example.myapplication2024.R;import androidx.activity.ComponentActivity;
import androidx.annotation.Nullable;
import androidx.fragment.app.FragmentActivity;/*** Activity*/
public class StepRankActivity extends FragmentActivity {public static void start(Context context) {Intent starter = new Intent(context, StepRankActivity.class);context.startActivity(starter);}@Overrideprotected void onCreate(@Nullable Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_step_rank);getSupportFragmentManager().beginTransaction().add(R.id.fragment_parent, new StepRankFragment()).commitAllowingStateLoss();}
}

StepRankAdapter.java

package com.example.myapplication2024.rank;import android.view.View;
import android.view.ViewGroup;import com.example.myapplication2024.R;import java.util.ArrayList;
import java.util.List;import androidx.annotation.NonNull;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;/*** 步数适配器*/
public class StepRankAdapter extends RecyclerView.Adapter<BaseHolder> {private static final int TYPE_TOP = -8123;private final StepRank[] mTopThreeData = new StepRank[3];private final List<StepRank> mData = new ArrayList<>();public void setData(List<StepRank> data) {mTopThreeData[0] = null;mTopThreeData[1] = null;mTopThreeData[2] = null;mData.clear();if (data != null) {for (int i = 0; i < data.size() && data.size() < 3; i++) {mTopThreeData[i] = data.get(i);}if (data.size() > 3) {mData.addAll(data.subList(3, data.size()));}}notifyDataSetChanged();}public void addAll(List<StepRank> data) {if (data != null) {mData.addAll(data);notifyDataSetChanged();}}@NonNull@Overridepublic BaseHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {if (viewType == TYPE_TOP) {return new BaseHolder(R.layout.item_step_rank_top, parent);}return new BaseHolder(R.layout.item_step_rank, parent);}@Overridepublic void onBindViewHolder(@NonNull BaseHolder holder, int position) {if (getItemViewType(position) == TYPE_TOP) {//前三.通过 holder.findViewById   对应item_step_rank_topreturn;}//其他 对应 item_step_rankholder.setText(R.id.tv_rank,String.valueOf(position+3));}@Overridepublic int getItemViewType(int position) {if (position == 0) {return TYPE_TOP;} else {return -1;}}@Overridepublic int getItemCount() {if (mData.isEmpty()) {for (StepRank topThreeDatum : mTopThreeData) {if (topThreeDatum != null) {return 1;}}return 0;} else {return mData.size() + 1;}}public void attachToRecyclerView(@NonNull RecyclerView recyclerView) {recyclerView.setLayoutManager(new LinearLayoutManager(recyclerView.getContext()));recyclerView.setAdapter(this);}static class StepRankHolder extends RecyclerView.ViewHolder {public StepRankHolder(@NonNull View itemView) {super(itemView);}}
}

StepRankFragment.java

package com.example.myapplication2024.rank;import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;import com.example.myapplication2024.R;import java.util.ArrayList;
import java.util.List;import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.RecyclerView;/*** Fragment*/
public class StepRankFragment extends Fragment {@Nullable@Overridepublic View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {return inflater.inflate(R.layout.fragment_step_rank, container, false);}@Overridepublic void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {super.onViewCreated(view, savedInstanceState);final RecyclerView recyclerView = view.findViewById(R.id.recycler_view);final StepRankAdapter adapter = new StepRankAdapter();adapter.attachToRecyclerView(recyclerView);final List<StepRank> data = new ArrayList<>();for (int i = 0; i < 20; i++) {data.add(new StepRank());}adapter.setData(data);}
}