利用Listview實現程序列表展示
先來看一下效果圖
這個Demo其實也沒有什麼難度，主要的難點就是在那兩個title上，下來我就帶大家看看去怎麼實現這個效果
首先獲取系統中安裝的應用信息
/** * 獲取應用程序信息 */ public class AppInfoTools { public static List<AppInfo> getAppInfo(Context context) { List<AppInfo> list = new ArrayList<>(); //獲取PackageManager PackageManager pm = context.getPackageManager(); //這裏的0指的是要獲取程序的基本信息 List<PackageInfo> packageInfos = pm.getInstalledPackages(0); for (PackageInfo packageInfo : packageInfos) { //包名 String packageName = packageInfo.packageName; //applica ApplicationInfo applicationInfo = packageInfo.applicationInfo; //應用名稱 Label String name = applicationInfo.loadLabel(pm).toString(); //圖標 Drawable drawable = applicationInfo.loadIcon(pm); //佔用空間大小 long size = new File(applicationInfo.sourceDir).length(); //程序標記 boolean isSystem = false; boolean isSD = false; //判斷是用戶還是系統程序 int flags = applicationInfo.flags; //系統程序 if ((flags & ApplicationInfo.FLAG_SYSTEM) != 0) { isSystem = true; } else { isSystem = false; } //是否在SD中 if ((flags & ApplicationInfo.FLAG_EXTERNAL_STORAGE) != 0) { isSD = true; } else { isSD = false; } list.add(new AppInfo(packageName, name, drawable, size, isSystem, isSD)); } return list; } }聲明listview並給其設置adapter
layout <ListView android:id="@+id/lv_softwarem" android:layout_width="match_parent" android:layout_height="match_parent"></ListView> //在這聲明個默認的title <TextView android:id="@+id/tv_softwarem_title" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="@android:color/holo_blue_bright" android:padding="8dp" android:text="用戶程序(0)" android:textSize="18sp" /> Activity public class MainActivity extends AppCompatActivity { //用戶程序集合 private List<AppInfo> userApp = new ArrayList<>(); //系統程序集合 private List<AppInfo> systemApp = new ArrayList<>(); private SoftWareAdapter myAdapter; private TextView tv_title; private ListView lv; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initView(); } private void initView() { tv_title = (TextView) findViewById(R.id.tv_softwarem_title); lv = (ListView) findViewById(R.id.lv_softwarem); initData(); } private void initData() { //當手機上APP很多時，這就是個耗時操作，所以需要放在子線程中 new Thread() { @Override public void run() { final List<AppInfo> appInfos = AppInfoTools.getAppInfo(MainActivity.this); for (AppInfo appInfo : appInfos) { //判斷應用程序信息，將應用程序存放到不同的集合中 if (appInfo.isSystem) { systemApp.add(appInfo); } else { userApp.add(appInfo); } } runOnUiThread(new Runnable() { @Override public void run() { //給默認title設置text tv_title.setText("用戶程序(" + userApp.size() + ")"); //設置adapter myAdapter = new SoftWareAdapter(MainActivity.this, systemApp, userApp); lv.setAdapter(myAdapter); } }); } }.start(); //設置滑動監聽 lv.setOnScrollListener(new AbsListView.OnScrollListener() { @Override public void onScrollStateChanged(AbsListView view, int scrollState) { } /** * 滾動時回調的方法 * @param view * @param firstVisibleItem 當前區域內可視的第一個item * @param visibleItemCount 當前區域內可視的item總數 * @param totalItemCount item總數 */ @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { if (userApp != null && systemApp != null) { if (firstVisibleItem >= userApp.size() + 1) { tv_title.setText("系統程序(" + systemApp.size() + ")"); } else { tv_title.setText("用戶程序(" + userApp.size() + ")"); } } } }); } }接下來就是我們的重頭戲了，創建adapter
public class SoftWareAdapter extends BaseAdapter { private List<AppInfo> userApp ; private List<AppInfo> systemApp; private Context context; public SoftWareAdapter(Context context, List<AppInfo> systemApp, List<AppInfo> userApp) { this.context = context; this.systemApp = systemApp; this.userApp = userApp; } @Override public int getCount() { return userApp.size() + systemApp.size() + 2; } @Override public Object getItem(int position) { return null; } @Override public long getItemId(int position) { return position; } //拿到指定position的條目類型 @Override public int getItemViewType(int position) { //標題佈局類型 if (position == 0 || position == userApp.size() + 1) { return 0; } //條目佈局 return 1; } //設置條目類型個數 @Override public int getViewTypeCount() { return 2; } @Override public View getView(int position, View convertView, ViewGroup parent) { //調用getItemViewType方法，根據條目的顯示的樣式類型，設置條目顯示相應的樣式 if (getItemViewType(position) == 0) { TextView textView = new TextView(context); textView.setTextSize(18); textView.setPadding(8, 8, 8, 8); textView.setBackgroundColor(Color.BLUE); //標題佈局類型 if (position == 0) { textView.setText("用戶程序(" + userApp.size() + ")"); } else { textView.setText("系統程序(" + systemApp.size() + ")"); } return textView; } else { if (convertView == null) { convertView = View.inflate(context, R.layout.item_software, null); convertView.setTag(new ViewHolder(convertView)); } ViewHolder viewHolder = (ViewHolder) convertView.getTag(); //判斷當前位置 AppInfo info; if (position <= userApp.size()) { info = userApp.get(position - 1); } else { info = systemApp.get(position - userApp.size() - 2); } viewHolder.icon.setImageDrawable(info.icon); viewHolder.name.setText(info.name); viewHolder.size.setText(android.text.format.Formatter.formatFileSize(context, info.size)); viewHolder.isSystem.setText(info.isSD ? "SD" : "手機內存"); return convertView; } } static class ViewHolder { public TextView name; public TextView isSystem; public TextView size; public ImageView icon; public ViewHolder(View item) { this.name = (TextView) item.findViewById(R.id.tv_item_software_name); this.icon = (ImageView) item.findViewById(R.id.iv_item_software); this.size = (TextView) item.findViewById(R.id.tv_item_software_size); this.isSystem = (TextView) item.findViewById(R.id.tv_item_software_issystem); } } }
這個Demo很簡單，相信大家看代碼就很容易看懂的，好了今天就寫到這了，
