儲存位圖檔案

Android OS 為每個應用程序保留獨立的文件結構.

例如:
com.AndroidBtmap 應用程序包的文件位於:
/data/data/com.AndroidBtmap/files/

修改上文"從 drawable 文件夾中加載位圖"程序, 把位圖檔案以 JPG 格式儲存於 /data/data/com.AndroidBtmap/files/ 中.




main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<ImageView  
    android:id="@+id/myimage"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    />
<TextView  
    android:id="@+id/myimagewidth"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    />
<TextView  
    android:id="@+id/myimageheight"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    />
<Button
    android:id="@+id/save"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Save"
    />
</LinearLayout>

package com.AndroidBtmap;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Bitmap.CompressFormat;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

public class AndroidBtmap extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        ImageView myImage = (ImageView)findViewById(R.id.myimage);
        TextView myImageWidth = (TextView)findViewById(R.id.myimagewidth);
        TextView myImageHeight = (TextView)findViewById(R.id.myimageheight);
        Button buttonSave = (Button)findViewById(R.id.save);

        final Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.androidbiancheng);
        int bitmapWidth  = bitmap.getWidth();
        int bitmapHeight = bitmap.getHeight();
        
        myImage.setImageBitmap(bitmap);
        myImageWidth.setText("Width: " + String.valueOf(bitmapWidth));
        myImageHeight.setText("Height: " + String.valueOf(bitmapHeight));
        
        buttonSave.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    // TODO Auto-generated method stub
    FileOutputStream fos;
    try {
     fos = openFileOutput("MyBitmap.jpg", MODE_WORLD_READABLE);
     bitmap.compress(CompressFormat.JPEG, 80, fos);
     fos.flush();
     fos.close();
    } catch (FileNotFoundException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    } catch (IOException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    }
    
   }});
    }
}