Java 如何从图库中拾取图像，裁剪并将其保存在数据分区中

我需要一些帮助 我想从gallery中选取一个图像，然后将其重新调整为自定义大小，例如480*800，然后将其放入数据分区的文件夹中（例如（/data/test_wall））。 我试了很多次谷歌搜索，但都没有

这是我到目前为止的代码，但我无法从图库中选择并保存图像给我强制关闭：

package com.example.walpaperpicker;

import java.io.FileOutputStream;
import android.os.Bundle;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {

private static final int PICK_FRPM_GALLERY = 1;

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

    Button button1  = (Button) findViewById(R.id.button1);

    button1.setOnClickListener(new View.OnClickListener() { 
        @Override
        public void onClick(View v) {
            PickPic();
        }

        private void PickPic() {
            // this code working for pick a picture with camera
             Intent cameraIntent = new Intent(
                    android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(cameraIntent, PICK_FRPM_GALLERY);

            // this code not working give me fc after i select picture from gallery see my logcat
            /*Intent GallaryIntent = new Intent();
            GallaryIntent.setType("image/*");
            GallaryIntent.setAction(Intent.ACTION_GET_CONTENT);

            startActivityForResult(GallaryIntent, PICK_FRPM_GALLERY);*/


        }
    });
}
@SuppressLint("SdCardPath")
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == PICK_FRPM_GALLERY) {
                Bitmap photo = (Bitmap) data.getExtras().get("data");
                ImageView test = (ImageView) findViewById(R.id.imageView1);
                test.setImageBitmap(photo);
                try {
                    //I want put it in data partition but i dont know this is for sdcard
                    FileOutputStream out = new FileOutputStream("/sdcard/wallpaper.png");
                    photo.compress(Bitmap.CompressFormat.PNG, 90, out);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }

/*i want crop output picture
 *to custom size for example 480*800
 *but i dont know.
 */
  }

manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.walpaperpicker"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="18" />
    <uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE"> </uses-permission>
    <uses-permission android:name="android.permission.READ_INTERNAL_STORAGE"> </uses-permission>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>


    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.walpaperpicker.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

谢谢你的帮助

---

我正在等待。

我已经写了几篇关于如何选择画廊图像或缩略图的文章，这将对您有所帮助

及

好的，让我试着解释一下它是如何工作的

1。我们需要创建从Gallary中挑选图像的意图

Intent i = new Intent(Intent.ACTION_PICK,android.provider.MediaStore  
                              .Images.Media.EXTERNAL_CONTENT_URI);  
startActivityForResult(i, RESULT_LOAD_IMAGE); 

Bitmap createImageThumbnail(String imagePath, int width, int height) {  
  BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();  
  bmpFactoryOptions.inJustDecodeBounds = true;  
  int heightRatio = (int) Math.ceil(bmpFactoryOptions.outHeight  
    / (float) height);  
  int widthRatio = (int) Math.ceil(bmpFactoryOptions.outWidth  
    / (float) width);  

  if (heightRatio > 1 || widthRatio > 1) {  
   if (heightRatio > widthRatio) {  
    bmpFactoryOptions.inSampleSize = heightRatio;  
   } else {  
    bmpFactoryOptions.inSampleSize = widthRatio;  
   }  
  }  
  bmpFactoryOptions.inJustDecodeBounds = false;  

  if (bitmap != null) {  
   bitmap.recycle();  
   bitmap = null;  
  }  

  bitmap = BitmapFactory.decodeFile(imagePath, bmpFactoryOptions);  
  return bitmap;  
 } 

2。在同一活动中，我们需要使用onActivityResult方法处理拾取的图像

@Override  
    protected void onActivityResult(int requestCode,   
                                     int resultCode, Intent data) {  
        super.onActivityResult(requestCode, resultCode, data);  

        if (requestCode == RESULT_LOAD_IMAGE &&   
                              resultCode == RESULT_OK && null != data) {  
            Uri selectedImage = data.getData();  
            String[] filePathColumn = { MediaStore.Images.Media.DATA };  

            Cursor cursor = getContentResolver().query(selectedImage,  
                    filePathColumn, null, null, null);  
            cursor.moveToFirst();  

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);  
            String picturePath = cursor.getString(columnIndex);  
            cursor.close(); 

            imageView = (ImageView) findViewById(R.id.imageView);

            //here you can call createImageThumbnail method passing (picturePath,480,800) 
            //and set the received bitmap imageview directly instead of storing in bitmap.
            // eg. imageView.setImageBitmap(createImageThumbnail( picturePath, 480, 800));


            imageView.setImageBitmap(BitmapFactory  
                            .decodeFile(picturePath));  

        }  


    }  

Bitmap createImageThumbnail(String imagePath, int width, int height) {  
  BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();  
  bmpFactoryOptions.inJustDecodeBounds = true;  
  int heightRatio = (int) Math.ceil(bmpFactoryOptions.outHeight  
    / (float) height);  
  int widthRatio = (int) Math.ceil(bmpFactoryOptions.outWidth  
    / (float) width);  

  if (heightRatio > 1 || widthRatio > 1) {  
   if (heightRatio > widthRatio) {  
    bmpFactoryOptions.inSampleSize = heightRatio;  
   } else {  
    bmpFactoryOptions.inSampleSize = widthRatio;  
   }  
  }  
  bmpFactoryOptions.inJustDecodeBounds = false;  

  if (bitmap != null) {  
   bitmap.recycle();  
   bitmap = null;  
  }  

  bitmap = BitmapFactory.decodeFile(imagePath, bmpFactoryOptions);  
  return bitmap;  
 } 

3。根据需要调整图像大小（宽度*高度）

Bitmap createImageThumbnail(String imagePath, int width, int height) {  
  BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();  
  bmpFactoryOptions.inJustDecodeBounds = true;  
  int heightRatio = (int) Math.ceil(bmpFactoryOptions.outHeight  
    / (float) height);  
  int widthRatio = (int) Math.ceil(bmpFactoryOptions.outWidth  
    / (float) width);  

  if (heightRatio > 1 || widthRatio > 1) {  
   if (heightRatio > widthRatio) {  
    bmpFactoryOptions.inSampleSize = heightRatio;  
   } else {  
    bmpFactoryOptions.inSampleSize = widthRatio;  
   }  
  }  
  bmpFactoryOptions.inJustDecodeBounds = false;  

  if (bitmap != null) {  
   bitmap.recycle();  
   bitmap = null;  
  }  

  bitmap = BitmapFactory.decodeFile(imagePath, bmpFactoryOptions);  
  return bitmap;  
 } 

---

如果您在这方面遇到任何问题，请告诉我。很乐意帮助。

谢谢，伙计，我尝试了您的代码，但在重新调整大小方面遇到了问题，我想您忘记了我想将图片放入数据分区的文件夹

//imageView.setImageBitmap（createimage缩略图（picturePath，480800））
bmpFactoryOptions.inJustDecodeBounds=false；if（bitmap！=null）{bitmap.recycle（）；bitmap=null；}bitmap=BitmapFactory.decodeFile（imagePath，bmpFactoryOptions）；返回位图；//我的位图和imagePath有错误（这不应该是“picturePath”？）不能在上面的行中让我编译}