Android开发05—Android常用高级控件（下）
Android开发05—Android常用高级控件（下）
1.滑块与进度条
1）ProgressBar类
ProgressBar类同样位于android.widget包下，但其继承自View，主要用于显示一些操作的进度。应用程序可以修改其长度表示当前后台操作的完成情况。因为进度条会移动，所以长时间加载某些资源或者执行某些耗时的操作时，不会使用户界面失去响应。
2）SeekBar类
SeekBar类继承自ProgressBar，是用来接收用户输入的控件。SeekBar类似于拖拉条，可以直观地显示用户需要的数据，常用于音量调节等场合。
3）实例：
main.xml
Activity:
Activity:
Activity：package qijia.si;import android.app.Activity;import android.app.TabActivity;import android.os.Bundle;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.BaseAdapter;import android.widget.Gallery;import android.widget.ImageView;import android.widget.ProgressBar;import android.widget.RatingBar;import android.widget.TabHost;public class JavaTest extends Activity { /** Called when the activity is first created. */int[] imageIds={R.drawable.bbta,R.drawable.bbtb,R.drawable.bbtc,R.drawable.bbtd,R.drawable.bbte,R.drawable.bbtf,R.drawable.bbtg}; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Gallery g1 = (Gallery)this.findViewById(R.id.gallery1); BaseAdapter ba = new BaseAdapter(){public int getCount() {// TODO Auto-generated method stubreturn imageIds.length;}public Object getItem(int position) {// TODO Auto-generated method stubreturn null;}public long getItemId(int position) {// TODO Auto-generated method stubreturn 0;}public View getView(int position, View convertView, ViewGroup parent) {// TODO Auto-generated method stubImageView iv = new ImageView(JavaTest.this);iv.setImageResource(imageIds[position]);iv.setScaleType(ImageView.ScaleType.FIT_XY);iv.setLayoutParams(new Gallery.LayoutParams(188,250));return iv;} }; g1.setAdapter(ba); g1.setOnItemClickListener( new OnItemClickListener(){public void onItemClick(AdapterView<?> arg0, View arg1,int arg2, long arg3) {// TODO Auto-generated method stubGallery g1 = (Gallery)findViewById(R.id.gallery1);g1.setSelection(arg2);} }); } }
