android基础课件全解.ppt

public class MenuActivity extends Activity { private static final String TAG = MenuActivity; private static final int MENU_ADD = Menu.FIRST; private static final int MENU_UPDATE = Menu.FIRST + 1; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.menu); } @Override public boolean onCreateOptionsMenu(Menu menu) { menu.add(Menu.NONE, MENU_ADD, Menu.NONE, 添加); menu.add(Menu.NONE, MENU_UPDATE, Menu.NONE, 更新); return super.onCreateOptionsMenu(menu); } @Override public boolean onMenuItemSelected(int featureId, MenuItem item) { switch (item.getItemId()) { case MENU_ADD: Log.i(TAG, add was selected); return true; case MENU_UPDATE: Log.i(TAG, update was selected); return true; default: return super.onMenuItemSelected(featureId, item); } } } * public class ProgressDialogActivity extends Activity { private ProgressDialog progressDialog; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.menu); //开始一条专门处理耗时工作的线程 new Thread(new Runnable(){ @Override public void run() { try { Thread.sleep(5*1000);//假设这项工作需要5秒才能完成 progressDialog.dismiss();//关闭进程对话框 //runOnUiThread(finishDialog);//要求运行在UI线程 } catch (InterruptedException e) {} } }).start(); progressDialog = ProgressDialog.show(ProgressDialogActivity.this, 请稍等, 数据正在加载中..., true); } private Runnable finishDialog = new Runnable() { @Override public void run() { progressDialog.dismiss(); } }; } * 下拉列表框--自定义选项界面样式 效果图: Spinner.getItemAtPosition(Spinner.getSelectedItemPosition());获取下拉列表框的值 调用setOnItemSelectedListener()方法，处理下拉列表框被选择事件，把AdapterView.OnItemSelectedListener实例作为参数传入 拖动条(SeekBar) 效果图: Se