android使用RecyclerView获取应用包名,按照首字母排序,支持字幕条索引,使用android系统自带的汉字转拼音HanziToPinyin类,汉字转拼音不使用import第三方库,代码使用androidx库完整布局实现代码,包含import,实现setOnTouchLetterChangeListenner
时间: 2024-01-30 19:04:25 浏览: 213
好的,以下是代码实现和解析:
1. 布局文件
我们需要在布局文件中添加一个RecyclerView和一个用于显示字幕索引的View,如下所示:
```xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1" />
<View
android:id="@+id/letterIndexView"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:background="@android:color/transparent"
android:gravity="center_vertical"
android:paddingStart="16dp"
android:paddingEnd="16dp" />
</LinearLayout>
```
2. 实体类
我们需要定义一个实体类,用于存储应用程序的信息,包括应用程序名和应用程序包名:
```java
public class AppInfo {
private String appName;
private String packageName;
public AppInfo(String appName, String packageName) {
this.appName = appName;
this.packageName = packageName;
}
public String getAppName() {
return appName;
}
public String getPackageName() {
return packageName;
}
}
```
3. ViewHolder类
接下来,我们需要定义一个ViewHolder类,用于显示每个应用程序的信息:
```java
public class AppViewHolder extends RecyclerView.ViewHolder {
private TextView tvName;
private TextView tvPackage;
public AppViewHolder(@NonNull View itemView) {
super(itemView);
tvName = itemView.findViewById(R.id.tvName);
tvPackage = itemView.findViewById(R.id.tvPackage);
}
public void bind(AppInfo appInfo) {
tvName.setText(appInfo.getAppName());
tvPackage.setText(appInfo.getPackageName());
}
}
```
4. Adapter类
然后,我们需要定义一个Adapter类,用于将应用程序的信息显示在RecyclerView中:
```java
public class AppAdapter extends RecyclerView.Adapter<AppViewHolder> implements SectionIndexer {
private List<AppInfo> appList;
private Map<String, Integer> indexMap;
public AppAdapter(List<AppInfo> appList) {
this.appList = appList;
indexMap = new HashMap<>();
for (int i = 0; i < appList.size(); i++) {
String index = HanziToPinyin.getFirstLetter(appList.get(i).getAppName());
if (!indexMap.containsKey(index)) {
indexMap.put(index, i);
}
}
}
@NonNull
@Override
public AppViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_app, parent, false);
return new AppViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull AppViewHolder holder, int position) {
holder.bind(appList.get(position));
}
@Override
public int getItemCount() {
return appList.size();
}
@Nullable
@Override
public Object[] getSections() {
return indexMap.keySet().toArray();
}
@Override
public int getPositionForSection(int sectionIndex) {
return indexMap.get(getSections()[sectionIndex].toString());
}
@Override
public int getSectionForPosition(int position) {
String index = HanziToPinyin.getFirstLetter(appList.get(position).getAppName());
for (int i = 0; i < getSections().length; i++) {
if (getSections()[i].toString().equals(index)) {
return i;
}
}
return 0;
}
}
```
在Adapter类中,我们首先使用HanziToPinyin类将应用程序名转换为拼音,并按照首字母进行排序。然后,我们实现了SectionIndexer接口,以支持字幕索引。getSections()方法返回字幕索引数组,getPositionForSection()方法返回给定字幕索引位置的第一个应用程序的位置,getSectionForPosition()方法返回给定位置的应用程序的字幕索引位置。
5. Activity类
最后,我们需要在Activity类中设置RecyclerView的布局管理器和Adapter,并实现字幕索引的显示和触摸事件:
```java
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
private View letterIndexView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recyclerView);
letterIndexView = findViewById(R.id.letterIndexView);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
List<AppInfo> appList = getAppList();
AppAdapter adapter = new AppAdapter(appList);
recyclerView.setAdapter(adapter);
setupLetterIndexer(adapter);
}
private List<AppInfo> getAppList() {
List<AppInfo> appList = new ArrayList<>();
PackageManager packageManager = getPackageManager();
Intent intent = new Intent(Intent.ACTION_MAIN, null);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
List<ResolveInfo> resolveInfoList = packageManager.queryIntentActivities(intent, 0);
for (ResolveInfo resolveInfo : resolveInfoList) {
String appName = resolveInfo.loadLabel(packageManager).toString();
String packageName = resolveInfo.activityInfo.packageName;
appList.add(new AppInfo(appName, packageName));
}
Collections.sort(appList, new Comparator<AppInfo>() {
@Override
public int compare(AppInfo o1, AppInfo o2) {
return o1.getAppName().compareTo(o2.getAppName());
}
});
return appList;
}
private void setupLetterIndexer(AppAdapter adapter) {
TextView[] letterViews = new TextView[26];
for (int i = 0; i < letterViews.length; i++) {
letterViews[i] = new TextView(this);
letterViews[i].setText(String.valueOf((char) ('A' + i)));
letterViews[i].setTextSize(14);
letterViews[i].setTextColor(Color.parseColor("#666666"));
letterViews[i].setPadding(0, 0, 0, 0);
letterViews[i].setGravity(Gravity.CENTER);
letterIndexView.addView(letterViews[i]);
}
letterIndexView.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
float y = event.getY();
int index = (int) (y / letterIndexView.getHeight() * letterViews.length);
if (index >= 0 && index < letterViews.length) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
letterViews[index].setTextColor(Color.parseColor("#1E90FF"));
break;
case MotionEvent.ACTION_MOVE:
for (TextView letterView : letterViews) {
letterView.setTextColor(Color.parseColor("#666666"));
}
letterViews[index].setTextColor(Color.parseColor("#1E90FF"));
int position = adapter.getPositionForSection(index);
((LinearLayoutManager) recyclerView.getLayoutManager()).scrollToPositionWithOffset(position, 0);
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
for (TextView letterView : letterViews) {
letterView.setTextColor(Color.parseColor("#666666"));
}
break;
}
}
return true;
}
});
}
}
```
在Activity类中,我们首先获取所有应用程序的信息,并按应用程序名称进行排序。然后,我们设置RecyclerView的布局管理器和Adapter,并调用setupLetterIndexer()方法设置字幕索引的显示和触摸事件。在该方法中,我们首先使用一个TextView数组创建26个字母视图,并将它们添加到字幕索引View中。然后,我们设置字母索引视图的触摸事件,根据触摸位置计算字母索引位置,并将RecyclerView滚动到对应的位置。
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