Android中截图功能

在实际应用中，经常需要对图片进行处理，包括压缩、截图等等，其实android系统提供了一个可以截图的activity，我们只需调用它就行了，下面示例完成一个通过相机照相或相册选取图片后对其截图的功能，其实知道图片的路劲都可以调用截图activity，代码如下：

测试activity：

package com.home.testclipimage;    import java.io.File;    import android.app.Activity;  import android.content.Intent;  import android.graphics.Bitmap;  import android.graphics.drawable.BitmapDrawable;  import android.net.Uri;  import android.os.Bundle;  import android.os.Environment;  import android.provider.MediaStore;  import android.provider.MediaStore.Images.Media;  import android.view.View;  import android.view.View.OnClickListener;  import android.widget.Button;  import android.widget.ImageView;  import android.widget.Toast;    public class TestClipImageActivity extends Activity implements OnClickListener {   private Button gallaryBtn;   private Button cameraBtn;   private ImageView showImage;   private File file;     @Override   protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);    gallaryBtn = (Button) findViewById(R.id.main_btn_gallery);    cameraBtn = (Button) findViewById(R.id.main_btn_camera);    gallaryBtn.setOnClickListener(this);    cameraBtn.setOnClickListener(this);    showImage = (ImageView) findViewById(R.id.main_image);   }     @Override   public void onClick(View v) {    if (v == gallaryBtn) {     // 跳转至相册界面     Intent intent = new Intent(Intent.ACTION_PICK,       Media.EXTERNAL_CONTENT_URI);     startActivityForResult(intent, 0);    }    if (v == cameraBtn) {     if (!Environment.MEDIA_MOUNTED.equals(Environment       .getExternalStorageState())) {      Toast.makeText(this, "请插入SD卡", Toast.LENGTH_SHORT).show();      return;     }     // 跳转至相机界面     Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);     file = new File(Environment.getExternalStorageDirectory(),       getPhotoName());     // 指定相机拍照后相片的存储位置     intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));     startActivityForResult(intent, 1);    }   }     @Override   protected void onActivityResult(int requestCode, int resultCode, Intent data) {    super.onActivityResult(requestCode, resultCode, data);    // 系统相册返回    if (requestCode == 0 && resultCode == Activity.RESULT_OK      && data != null) {     startPhotoZoom(data.getData(), 150);// 截图    }    // 系统相机返回    if (requestCode == 1 && resultCode == Activity.RESULT_OK) {     startPhotoZoom(Uri.fromFile(file), 150);// 截图    }    // 截图后返回    if (requestCode == 2 && data != null) {     Bundle bundle = data.getExtras();     if (bundle != null) {      Bitmap bitmap = bundle.getParcelable("data");      showImage.setBackgroundDrawable(new BitmapDrawable(bitmap));     }    }   }     /**    * 跳转至系统截图界面进行截图    *     * @param data    * @param size    */   private void startPhotoZoom(Uri data, int size) {    Intent intent = new Intent("com.android.camera.action.CROP");    intent.setDataAndType(data, "image/*");    // crop为true时表示显示的view可以剪裁    intent.putExtra("crop", "true");    // aspectX aspectY 是宽高的比例    intent.putExtra("aspectX", 1);    intent.putExtra("aspectY", 1);    // outputX,outputY 是剪裁图片的宽高    intent.putExtra("outputX", size);    intent.putExtra("outputY", size);    intent.putExtra("return-data", true);    startActivityForResult(intent, 2);   }     /**    * 产生照片名称    *     * @return    */   private String getPhotoName() {    String name = System.currentTimeMillis() + ".jpg";    return name;   }  }

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"      android:layout_width="match_parent"      android:layout_height="match_parent"      android:orientation="vertical" >        <LinearLayout          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:gravity="center_horizontal"          android:orientation="horizontal" >            <Button              android:id="@+id/main_btn_gallery"              android:layout_width="wrap_content"              android:layout_height="wrap_content"              android:text="相册" />            <Button              android:id="@+id/main_btn_camera"              android:layout_width="wrap_content"              android:layout_height="wrap_content"              android:text="相机" />      </LinearLayout>        <ImageView          android:id="@+id/main_image"          android:layout_width="150dp"          android:layout_height="150dp"          android:layout_gravity="center_horizontal"          android:layout_marginTop="30dp" />    </LinearLayout>

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