Question

##MyDraw.java##

这部分代码是创建位图图像的位置，位图位于画布上，形成这一点我希望能够保存在位图上创建的图像，我有一个下拉菜单带有“保存”选项的MainActivity。

package com.example.save_file;

import java.util.Random;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.view.View;
import android.view.MotionEvent;

public class MyDraw extends View

{

 Canvas c;
 Bitmap bmp;
 Paint paint;
 Random g;
 float X, Y;

 public MyDraw (Context context)

 {

      super(context);

      g = new Random ();        
      Bitmap.Config conf = Bitmap.Config.ARGB_8888; 
      bmp = Bitmap.createBitmap (1100, 1800, conf);               

      paint = new Paint ();
      paint.setStyle (Paint.Style.STROKE);
      paint.setColor (Color.WHITE);         

      this.setOnTouchListener (new OnTouchListener() 
      {
          public boolean onTouch (View v, MotionEvent event) 

          {

                int h, w, R, G, B, A;
                float x, y;

                c = new Canvas (bmp);                    

                x = event.getX ();
                y = event.getY ();
                System.out.printf ("%f %f\n", X, Y);                    

                paint.setAntiAlias (true);

                w = g.nextInt (70)+90;
                h = g.nextInt (70);

                R = g.nextInt (255);
                G = g.nextInt (255);
                B = g.nextInt (255);
                A = g.nextInt (255);

                paint.setStyle (Paint.Style.FILL);
                paint.setColor ((A << 24) + (R << 16) + (G << 8) + (B << 0));

                if (MyApp.fill == 0) // FILLED SHAPE
                {
                     paint.setStyle (Paint.Style.FILL);
                     paint.setColor ((A << 24) + (R << 16) + (G << 8) + (B << 0));

                     if (MyApp.shape == 0)
                          c.drawRect (x, y, x + w, y + h, paint);
                     else
                          c.drawOval(new RectF (x, y, x + w, y + h), paint);

                     paint.setStyle (Paint.Style.STROKE);
                     paint.setColor (Color.BLACK);                                       

                     if (MyApp.shape == 0)
                          c.drawRect (x, y, x + w, y + h, paint);
                else
                          c.drawOval(new RectF (x, y, x + w, y + h), paint);
                }
                else // OUTLINED SHAPE
                {
                     paint.setStyle (Paint.Style.STROKE);
                     paint.setColor ((A << 24) + (R << 16) + (G << 8) + (B << 0));            
                     if (MyApp.shape == 0)
                          c.drawRect (x, y, x + w, y + h, paint);
                     else
                          c.drawOval(new RectF (x, y, x + w, y + h), paint);
                }                                  
                paint.setColor (Color.WHITE);
                invalidate ();                   
                return true;

          }


          });

     }
     @Override
     protected void onDraw (Canvas c)
     {         
      super.onDraw (c);
      c.drawBitmap (bmp, 0, 0, paint);
     }
}

##MyApp.java##

    package com.example.save_file;

public class MyApp 

{

 static public int shape = 0;
 static public int fill = 0;

}


##MainActivity.java##

这是菜单代码所在代码的一部分，我希望能够在此处保存保存按钮，并将位图图像保存到手机中，最好是标准图库文件夹。

package com.example.save_file;

import java.io.File;
import java.io.FileOutputStream;
import java.util.Random;

import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.view.Menu;
//import android.gesture.GestureOverlayView;

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        MyDraw d = new MyDraw (this);
        setContentView (d);
    }       

    @Override
    public boolean onCreateOptionsMenu(Menu menu) 
    {
          super.onCreateOptionsMenu (menu);
          MenuItem menu1 = menu.add(0, 0, Menu.NONE, "Filled Shape");
          MenuItem menu2 = menu.add(0, 1, Menu.NONE, "Outline Shape");
          MenuItem menu3 = menu.add(0, 2, Menu.NONE, "Rectangle");
          MenuItem menu4 = menu.add(0, 3, Menu.NONE, "Oval");
          MenuItem menu5 = menu.add(0, 4, Menu.NONE, "Save!");

          return true;
     }
     public boolean onOptionsItemSelected(MenuItem item) 
     {
          switch (item.getItemId()) 

          {
          case 0:
               MyApp.fill = 0;
               return true;
          case 1:
               MyApp.fill = 1;
               return true;
          case 2:
               MyApp.shape = 0;
               return true;
          case 3:
               MyApp.shape = 1;
               return true;
          default:
               return super.onOptionsItemSelected(item);

           case 4:

               bmp.setDrawingCacheEnabled(true);
                Bitmap bitmap = bmp.getDrawingCache();
                File root = Environment.getExternalStorageDirectory();
                File file = new
                    File(root.getAbsolutePath()+"/DCIM/Camera/img.jpg");
                try 
                {
                    file.createNewFile();
                    FileOutputStream ostream = new FileOutputStream(file);
                    bitmap.compress(CompressFormat.JPEG, 100, ostream);
                    ostream.close();
                } 
                catch (Exception e) 
                {
                    e.printStackTrace();
                } 
                   }
     }

}

Answer 1

我使用此代码来保存使用画布绘制的任何图形，如fingerpaint或类似图片，我希望对您的案例有用

将实例设置为全局

MyDraw d;
@Override
public void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    d = new MyDraw (this);
    setContentView (d);
}

并将其放在onOptionsItemSelected（）;

的情况下

case 4:
    try {
        Bitmap bitmap = Bitmap.createBitmap(d.getWidth(),d.getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bitmap);
        d.draw(canvas);
        File folder = new File(Environment.getExternalStorageDirectory()+ "/DCIM/Camera/");
        if (!folder.exists())
            folder.mkdirs();
        String fileName = Environment.getExternalStorageDirectory()+ "/DCIM/Camera/img.jpg"";
        if (new File(fileName).exists())
            new File(fileName).delete();
        OutputStream stream = new FileOutputStream(fileName);
        /*
         * Write bitmap to file using JPEG or PNG and 100% quality hint
         * for JPEG.
         */
        bitmap.compress(CompressFormat.JPEG, 100, stream);
        stream.close();
        } catch (Exception e) {
                // TODO Auto-generated catch block
                Toast.makeText(this, "Error: " + e.getMessage(),Toast.LENGTH_LONG).show();
        }
        break;

更新：检查您的模拟设备是否有SD卡 enter image description here

提醒您必须向清单添加权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

保存位图图像

1 个答案: