Android显示相册图片和相机拍照

Posted 2020-10-07 sysu_huangwei

首先看最重要的MainActive类：

 

 1 public class MainActivity extends AppCompatActivity {
 2 
 3     private final int FROM_ALBUM = 1;//表示从相册获取照片
 4     private final int FROM_CAMERA = 2;//表示从相机获取照片
 5     private ImageView imageView;
 6 
 7     @Override
 8     protected void onCreate(Bundle savedInstanceState) {
 9         super.onCreate(savedInstanceState);
10         setContentView(R.layout.activity_main);
11     }
12 
13     // 打开相册
14     public void onClickAlbum(View view){
15         Intent intent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
16         startActivityForResult(intent, FROM_ALBUM);
17     }
18 
19     // 打开相机
20     public void onClickCamera(View view){
21         Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
22         startActivityForResult(intent, FROM_CAMERA);
23     }
24 
25     @Override
26     protected void onActivityResult(int requestCode, int resultCode, Intent data){
27 
28         //从相册返回
29         if(requestCode == FROM_ALBUM  &&  resultCode == Activity.RESULT_OK  &&  data != null){
30             imageView = (ImageView)findViewById(R.id.imageView);
31             Uri imageUri = data.getData();
32             ContentResolver cr = this.getContentResolver();
33             try {
34                 Bitmap bitmap = BitmapFactory.decodeStream(cr.openInputStream(imageUri));
40                 imageView.setImageBitmap(bitmap);
41             }catch (FileNotFoundException e){
42                 Log.e("Exception", e.getMessage(), e);
43             }
44         }
45 
46         //从相机返回
47         if(requestCode == FROM_CAMERA  &&  resultCode == Activity.RESULT_OK  &&  data != null){
48             imageView = (ImageView)findViewById(R.id.imageView);
49             Bitmap photo = (Bitmap) data.getExtras().get("data");
50 
51             imageView.setImageBitmap(photo);
52         }
53 
54         super.onActivityResult(requestCode, resultCode, data);
55     }
56 
57 }

 

 

上面两个按钮的处理函数名称在布局中定义，布局如下：两个button（一个打开相册，一个打开相机），一个imageview

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:app="http://schemas.android.com/apk/res-auto"
 4     xmlns:tools="http://schemas.android.com/tools"
 5     android:layout_width="match_parent"
 6     android:layout_height="match_parent"
 7     tools:context="com.meitu.graydemo.MainActivity">
 8 
 9 <LinearLayout
10     android:layout_width="368dp"
11     android:layout_height="wrap_content"
12     android:orientation="vertical"
13     tools:layout_editor_absoluteY="0dp"
14     tools:layout_editor_absoluteX="8dp">
15 
16     <LinearLayout
17         android:id="@+id/buttonLayout"
18         android:layout_width="fill_parent"
19         android:layout_height="wrap_content"
20         android:orientation="horizontal">
21 
22         <Button
23             android:id="@+id/button"
24             android:layout_width="wrap_content"
25             android:layout_height="wrap_content"
26             android:onClick="onClickAlbum"
27             android:text="打开相册"
28             tools:layout_editor_absoluteX="16dp"
29             tools:layout_editor_absoluteY="16dp" />
30 
31         <Button
32             android:id="@+id/button2"
33             android:layout_width="wrap_content"
34             android:layout_height="wrap_content"
35             android:onClick="onClickCamera"
36             android:text="打开相机"
37             tools:layout_editor_absoluteX="280dp"
38             tools:layout_editor_absoluteY="16dp" />
39     </LinearLayout>
40 
41     <ImageView
42         android:id="@+id/imageView"
43         android:layout_width="wrap_content"
44         android:layout_height="wrap_content"
45         app:srcCompat="@android:color/holo_blue_bright"
46         tools:layout_editor_absoluteX="16dp"
47         tools:layout_editor_absoluteY="48dp" />
48 
49 
50 </LinearLayout>
51 
52 
53 
54 
55 </android.support.constraint.ConstraintLayout>