问如何在用Delphi拍摄相机意图照片后从Android画廊删除图像

EN

unit Misc.Android;

interface

uses
  SysUtils,
  Androidapi.JNI.GraphicsContentViewText, Androidapi.Helpers, Androidapi.JNI.JavaTypes,
  Androidapi.JNIBridge, Androidapi.JNI.Provider;

type
  TGallery = class
  public
    class function GetLastImageID: integer;
    class function GetNextImageIDFromID(aFromID: integer; out aImagePath: string): integer;
    class function DeleteImageByID(aID: integer): boolean;
  end;


implementation

const
  _ID = '_id'; //  TJBaseColumns.JavaClass._ID   // uri in Androidapi.JNI.Provider

{ TGallery }

{If you're using action TakePhotoFromCameraAction remember to set NeedSaveToAlbum to true.
 It does not work, because of Android problems, but it can work in future.}

class function TGallery.GetLastImageID: integer;
var
  vContent: JContentResolver;
  vValues: TJavaObjectArray<JString>;
  vOrderBy: JString;
  vCursor: JCursor;
begin
  Result := -1;
  vContent := TAndroidHelper.Activity.getContentResolver;

  vValues := TJavaObjectArray<JString>.Create(1);
  vValues[0] := TJBaseColumns.JavaClass._ID;

  vOrderBy := StringToJString(_ID + ' DESC');

  vCursor := vContent.query(TJImages_Media.JavaClass.EXTERNAL_CONTENT_URI,
      vValues, nil, nil, vOrderBy);
  try
    if vCursor.moveToFirst then
      Result := vCursor.getInt( vCursor.getColumnIndex(TJBaseColumns.JavaClass._ID) );
  finally
    vCursor.close;
  end
end;

// Result is next Image ID and its aImagePath - is path to jpg image
class function TGallery.GetNextImageIDFromID(aFromID: integer; out aImagePath: string): integer;
var
  vContent: JContentResolver;
  vValues: TJavaObjectArray<JString>;
  vFilter: JString;
  vOrderBy: JString;
  vArgs : TJavaObjectArray<JString>;
  vCursor: JCursor;
begin
  Result := -1;
  aImagePath := '';
  vContent := TAndroidHelper.Activity.getContentResolver;
  vValues := TJavaObjectArray<JString>.Create(2);
  vValues[0] := TJMediaStore_MediaColumns.JavaClass.DATA;
  vValues[1] := TJBaseColumns.JavaClass._ID;
   // vValues[1] := TJMediaStore_MediaColumns.JavaClass.SIZE;
   // vValues[1] := TJImages_ImageColumns.JavaClass.DATE_TAKEN;

  vOrderBy := StringToJString(_ID + ' DESC');
  vFilter := StringToJString(_ID + '>?');
  vArgs := TJavaObjectArray<JString>.Create(1);  
  vArgs[0] := StringToJString(aFromID.ToString);

  vCursor := vContent.query(TJImages_Media.JavaClass.EXTERNAL_CONTENT_URI,
     vValues, vFilter, vArgs, vOrderBy);
  try
    if (vCursor.getCount > 0) and vCursor.moveToFirst then
    begin
      Result := vCursor.getInt( vCursor.getColumnIndex(TJBaseColumns.JavaClass._ID) );
      // vCursor.getLong(imageCursor.getColumnIndex(MediaStore.Images.Media.DATE_TAKEN));
      //vSize := wCursor.getLong(wCursor.getColumnIndex(TJMediaStore_MediaColumns.JavaClass.SIZE));
      aImagePath := JStringToString(vCursor.getString(
          vCursor.getColumnIndex(TJMediaStore_MediaColumns.JavaClass.DATA) ));
    end;
  finally
    vCursor.close;
  end;
end;

class function TGallery.DeleteImageByID(aID: integer): boolean;
var
  vContent: JContentResolver;
begin
  vContent := TAndroidHelper.Activity.getContentResolver;
  Result := vContent.delete(TJImages_Media.JavaClass.EXTERNAL_CONTENT_URI,
        StringToJString(_ID + '=' + aID.ToString), nil) = 1;
end;

end.