Android记事本的开发

Android记事本的开发

package com.jikexueyuan.hellonotes;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class NotesDB extends SQLiteOpenHelper {

public static final String TABLE_NAME = "notes";
public static final String CONTENT = "content";
public static final String PATH = "path";
public static final String VIDEO = "video";
public static final String ID = "_id";
public static final String TIME = "time";

public NotesDB(Context context) {
super(context, "notes", null, 1);
}

@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + " (" + ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT," + CONTENT
+ " TEXT NOT NULL," + PATH + " TEXT NOT NULL," + VIDEO
+ " TEXT NOT NULL," + TIME + " TEXT NOT NULL)");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

}

package com.jikexueyuan.hellonotes;

import android.annotation.SuppressLint;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.media.ThumbnailUtils;
import android.provider.MediaStore;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MyAdapter extends BaseAdapter {

private Context context;
private Cursor cursor;
private LinearLayout layout;

public MyAdapter(Context context, Cursor cursor) {
this.context = context;
this.cursor = cursor;
}

@Override
public int getCount() {
return cursor.getCount();
}

@Override
public Object getItem(int position) {
return cursor.getPosition();
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

public View getView(int position, View convertView, ViewGroup parent) {

LayoutInflater inflater = LayoutInflater.from(context);
layout = (LinearLayout) inflater.inflate(R.layout.cell, null);
TextView contenttv = (TextView) layout.findViewById(R.id.list_content);
TextView timetv = (TextView) layout.findViewById(R.id.list_time);
ImageView imgiv = (ImageView) layout.findViewById(R.id.list_img);
ImageView videoiv = (ImageView) layout.findViewById(R.id.list_video);
cursor.moveToPosition(position);
String content = cursor.getString(cursor.getColumnIndex("content"));
String time = cursor.getString(cursor.getColumnIndex("time"));
String url = cursor.getString(cursor.getColumnIndex("path"));
String urlvideo = cursor.getString(cursor.getColumnIndex("video"));
contenttv.setText(content);
timetv.setText(time);
videoiv.setImageBitmap(getVideoThumbnail(urlvideo, 200, 200,
MediaStore.Images.Thumbnails.MICRO_KIND));
imgiv.setImageBitmap(getImageThumbnail(url, 200, 200));
return layout;
}

public Bitmap getImageThumbnail(String uri, int width, int height) {
Bitmap bitmap = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeFile(uri, options);
options.inJustDecodeBounds = false;
int beWidth = options.outWidth / width;
int beHeight = options.outHeight / height;
int be = 1;
if (beWidth < beHeight) {
be = beWidth;
} else {
be = beHeight;
}
if (be <= 0) {
be = 1;
}
options.inSampleSize = be;
bitmap = BitmapFactory.decodeFile(uri, options);
bitmap = ThumbnailUtils.extractThumbnail(bitmap, width, height,
ThumbnailUtils.OPTIONS_RECYCLE_INPUT);
return bitmap;
}

private Bitmap getVideoThumbnail(String uri, int width, int height, int kind) {
Bitmap bitmap = null;
bitmap = ThumbnailUtils.createVideoThumbnail(uri, kind);
bitmap = ThumbnailUtils.extractThumbnail(bitmap, width, height,
ThumbnailUtils.OPTIONS_RECYCLE_INPUT);

return bitmap;
}

}

package com.jikexueyuan.hellonotes;

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;

public class MainActivity extends Activity implements OnClickListener {

private Button textbtn, imgbtn, videobtn;
private ListView lv;
private Intent i;
private MyAdapter adapter;
private NotesDB notesDB;
private SQLiteDatabase dbReader;
private Cursor cursor;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}

public void initView() {
lv = (ListView) findViewById(R.id.list);
textbtn = (Button) findViewById(R.id.text);
imgbtn = (Button) findViewById(R.id.img);
videobtn = (Button) findViewById(R.id.video);
textbtn.setOnClickListener(this);
imgbtn.setOnClickListener(this);
videobtn.setOnClickListener(this);
notesDB = new NotesDB(this);
dbReader = notesDB.getReadableDatabase();
lv.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
cursor.moveToPosition(position);
Intent i = new Intent(MainActivity.this, SelectAct.class);
i.putExtra(NotesDB.ID,
cursor.getInt(cursor.getColumnIndex(NotesDB.ID)));
i.putExtra(NotesDB.CONTENT, cursor.getString(cursor
.getColumnIndex(NotesDB.CONTENT)));
i.putExtra(NotesDB.TIME,
cursor.getString(cursor.getColumnIndex(NotesDB.TIME)));
i.putExtra(NotesDB.PATH,
cursor.getString(cursor.getColumnIndex(NotesDB.PATH)));
i.putExtra(NotesDB.VIDEO,
cursor.getString(cursor.getColumnIndex(NotesDB.VIDEO)));
startActivity(i);
}
});
}

@Override
public void onClick(View v) {
i = new Intent(this, AddContent.class);
switch (v.getId()) {
case R.id.text:
i.putExtra("flag", "1");
startActivity(i);
break;

case R.id.img:
i.putExtra("flag", "2");
startActivity(i);
break;

case R.id.video:
i.putExtra("flag", "3");
startActivity(i);
break;
}
}

public void selectDB() {
cursor = dbReader.query(NotesDB.TABLE_NAME, null, null, null, null,
null, null);
adapter = new MyAdapter(this, cursor);
lv.setAdapter(adapter);
}

@Override
protected void onResume() {
super.onResume();
selectDB();
}

<span style="color:#ff0000;">}
</span>

public Bitmap getImageThumbnail(String uri, int width, int height) {
Bitmap bitmap = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeFile(uri, options);
options.inJustDecodeBounds = false;
int beWidth = options.outWidth / width;
int beHeight = options.outHeight / height;
int be = 1;
if (beWidth < beHeight) {
be = beWidth;
} else {
be = beHeight;
}
if (be <= 0) {
be = 1;
}
options.inSampleSize = be;
bitmap = BitmapFactory.decodeFile(uri, options);
bitmap = ThumbnailUtils.extractThumbnail(bitmap, width, height,
ThumbnailUtils.OPTIONS_RECYCLE_INPUT);
return bitmap;
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity" >

<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >

<Button
android:id="@+id/btnText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="文字" />

<Button
android:id="@+id/btnimg"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="图文" />

<Button
android:id="@+id/btnvideo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="视频" />
</LinearLayout>
<ListView
android:id="@+id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
</ListView>

</LinearLayout>