呼叫攝像頭拍照和選擇相簿

NO IMAGE

1.activity_main.xml 佈局檔案 

   

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:tools="http://schemas.android.com/tools"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:orientation="vertical"
              tools:context="com.sh.cameraalbumnew.MainActivity">
<Button
        android:id="@ id/take_photo"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="take photo"/>
<Button
        android:id="@ id/choose_album"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="choose from album"/>
<ImageView
        android:id="@ id/picture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"/>
</LinearLayout>
2.MainActivity.java 主檔案
  
public class MainActivity extends AppCompatActivity {
public static final int TAKE_PHOTO = 1;
public static final int CHOOSE_PHOTO = 2;
private Button mTakePhoto, mChoosePhoto;
private ImageView picture;
private Uri imageUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTakePhoto = (Button) findViewById(R.id.take_photo);
mChoosePhoto = (Button) findViewById(R.id.choose_album);
picture = (ImageView) findViewById(R.id.picture);
mTakePhoto.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//建立file物件,用於儲存拍照後的圖片;
                File outputImage = new File(getExternalCacheDir(), "output_image.jpg");
try {
if (outputImage.exists()) {
outputImage.delete();
}
outputImage.createNewFile();
} catch (Exception e) {
e.printStackTrace();
}
if (Build.VERSION.SDK_INT >= 24) {
imageUri = FileProvider.getUriForFile(MainActivity.this,
"com.sh.cameraalbumnew.fileprovider", outputImage);
} else {
imageUri = Uri.fromFile(outputImage);
}
//啟動相機程式
                Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
startActivityForResult(intent, TAKE_PHOTO);
}
});
mChoosePhoto.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
} else {
openAlbum();
}
}
});
}
//開啟相簿
    private void openAlbum() {
Intent intent = new Intent("android.intent.action.GET_CONTENT");
intent.setType("image/*");
startActivityForResult(intent, CHOOSE_PHOTO);
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
switch (requestCode) {
case 1:
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
openAlbum();
} else {
Toast.makeText(this, "you denied the permission", Toast.LENGTH_SHORT).show();
}
break;
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case TAKE_PHOTO:
if (resultCode == RESULT_OK) {
try {
Bitmap bm = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
picture.setImageBitmap(bm);
} catch (Exception e) {
e.printStackTrace();
}
}
break;
case CHOOSE_PHOTO:
if (resultCode == RESULT_OK) {
if (Build.VERSION.SDK_INT >= 19) {  //4.4及以上的系統使用這個方法處理圖片;
                        handleImageOnKitKat(data);
} else {
handleImageBeforeKitKat(data);  //4.4及以下的系統使用這個方法處理圖片
                    }
}
default:
break;
}
}
private void handleImageBeforeKitKat(Intent data) {
Uri uri = data.getData();
String imagePath = getImagePath(uri, null);
displayImage(imagePath);
}
private String getImagePath(Uri uri, String selection) {
String path = null;
//通過Uri和selection來獲取真實的圖片路徑
        Cursor cursor = getContentResolver().query(uri, null, selection, null, null);
if (cursor != null) {
if (cursor.moveToFirst()) {
path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
}
cursor.close();
}
return path;
}
private void displayImage(String imagePath) {
if (imagePath != null) {
Bitmap bitmap = BitmapFactory.decodeFile(imagePath);
picture.setImageBitmap(bitmap);
} else {
Toast.makeText(this, "failed to get image", Toast.LENGTH_SHORT).show();
}
}
/**
     * 4.4及以上的系統使用這個方法處理圖片
     *
     * @param data
     */
    @TargetApi(19)
private void handleImageOnKitKat(Intent data) {
String imagePath = null;
Uri uri = data.getData();
if (DocumentsContract.isDocumentUri(this, uri)) {
//如果document型別的Uri,則通過document來處理
            String docID = DocumentsContract.getDocumentId(uri);
if ("com.android.providers.media.documents".equals(uri.getAuthority())) {
String id = docID.split(":")[1];     //解析出數字格式的id
                String selection = MediaStore.Images.Media._ID   "="   id;
imagePath = getImagePath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, selection);
} else if ("com.android.providers.downloads.documents".equals(uri.getAuthority())) {
Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/piblic_downloads"), Long.valueOf(docID));
imagePath = getImagePath(contentUri, null);
}
} else if ("content".equalsIgnoreCase(uri.getScheme())) {
//如果是content型別的uri,則使用普通方式使用
            imagePath = getImagePath(uri, null);
} else if ("file".equalsIgnoreCase(uri.getScheme())) {
//如果是file型別的uri,直接獲取路徑即可
            imagePath = uri.getPath();
}
displayImage(imagePath);
}
  
3. file_paths.xml 
<?xml version = "1.0" encoding = "utf-8"?>
<paths xmlns:android = "http://schemas.android.com/apk/res/android">
<external-path name = "my_images" path = "">
</external-path>
</paths>
4.manifests.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest package="com.sh.cameraalbumnew"
          xmlns:android="http://schemas.android.com/apk/res/android">
<application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<provider
            android:authorities="com.sh.cameraalbumnew.fileprovider"
            android:name="android.support.v4.content.FileProvider"
            android:exported="false"
            android:grantUriPermissions="true">
<meta-data android:name="android.support.FILE_PROVIDER_PATHS"
                       android:resource="@xml/file_paths"/>
</provider>
</application>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>