package zhang.ya;
 
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
 
import android.app.Activity;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.sqliteDatabase;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AutoCompleteTextView;
import android.widget.Button;
import android.widget.CursorAdapter;
import android.widget.TextView;
 
public class Test00 extends Activity implements TextWatcher,OnClickListener
{
	private final String DATABASE_PATH = android.os.Environment.getExternalStorageDirectory().getAbsolutePath()
			+ "/course_name";
	private AutoCompleteTextView courseName;
	private final String DATABASE_FILENAME = "course_name.db3";
	private sqliteDatabase database;
	private Button btnSelectWord;
 
	@Override
	public void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
 
		setContentView(R.layout.main);
		database = openDatabase();
		courseName = (AutoCompleteTextView) findViewById(R.id.courseName);
		courseName.setThreshold(1);
		courseName.addTextChangedListener(this);
		btnSelectWord = (Button) findViewById(R.id.buttonName);
		btnSelectWord.setOnClickListener(this);
	}
 
	public class CourseNameAdapter extends CursorAdapter
	{
		private LayoutInflater layoutInflater;
 
		@Override
		public CharSequence convertToString(Cursor cursor)
		{
			return cursor == null ? "" : cursor.getString(cursor.getColumnIndex("course_name"));
		}
 
		private void setView(View view,Cursor cursor)
		{
			TextView tvWordItem = (TextView) view;
			tvWordItem.setText(cursor.getString(cursor.getColumnIndex("course_name")));
		}
 
		@Override
		public void bindView(View view,Context context,Cursor cursor)
		{
			setView(view,cursor);
		}
 
		@Override
		public View newView(Context context,Cursor cursor,ViewGroup parent)
		{
			View view = layoutInflater.inflate(R.layout.word_list_item,null);
			setView(view,cursor);
			return view;
		}
 
		public CourseNameAdapter(Context context,Cursor c,boolean autoRequery)
		{
			super(context,autoRequery);
			layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
		}
	}
 
	//输入为空则使得确定按钮失效,只有输入了数据才使得按钮处于活动状态
	@Override
	public void afterTextChanged(Editable s)
	{
		Log.i("zhangya","textchage");
		String contentStr = s.toString();
		
		if (contentStr == null || contentStr.length() <= 0)//判断contentStr是否为空,判断字符串是否为空典型写法
		{
			Log.i("zhangya","afterTextChanged null");
			btnSelectWord.setEnabled(false);//为空则不是能按钮
 
		} else
		{
			Log.i("zhangya","afterTextChanged not null");
			btnSelectWord.setEnabled(true);
			Cursor cursor = database.rawQuery("select * from course_name where course_name like ?",new String[]
			{ contentStr + "%" });
 
			CourseNameAdapter dictionaryAdapter = new CourseNameAdapter(this,true);
			courseName.setAdapter(dictionaryAdapter);
		}
	}
 
	@Override
	public void beforeTextChanged(CharSequence s,int start,int count,int after)
	{
		// TODO Auto-generated method stub
 
	}
 
	@Override
	public void onTextChanged(CharSequence s,int before,int count)
	{
 
	}
 
	private sqliteDatabase openDatabase()
	{
		try
		{
			String databaseFilename = DATABASE_PATH + "/" + DATABASE_FILENAME;
			File dir = new File(DATABASE_PATH);
			if (!dir.exists())
				dir.mkdir();
			if (!(new File(databaseFilename)).exists())
			{
				InputStream is = getResources().openRawResource(R.raw.course_name);
				FileOutputStream fos = new FileOutputStream(databaseFilename);
				byte[] buffer = new byte[8192];
				int count = 0;
				while ((count = is.read(buffer)) > 0)
				{
					fos.write(buffer,count);
				}
 
				fos.close();
				is.close();
			}
			sqliteDatabase database = sqliteDatabase.openOrCreateDatabase(databaseFilename,null);
			return database;
		} catch (Exception e)
		{
		}
		return null;
	}
 
	@Override
	public void onClick(View v)
	{
		String sql = "select * from course_name where course_name=?";
		Cursor cursor = database.rawQuery(sql,new String[]
		{ courseName.getText().toString() });
		if (cursor.getCount() == 0)//没有同名记录,则插入数据
		{
			sql = "insert into course_name(course_name)values(?)";
			database.execsql(sql,new Object[]
			{ courseName.getText().toString() });
		} else
		{
			Log.i("zhangya","else");
		}
		cursor.moveToFirst();
 
	}
 
}

1.未输入时状态:

2.输入后: