訪問日曆安卓與德爾福

Question

我有一個問題，與Jstring下Delphi-XE5 Android應用程序。其實，我嘗試使用下面的句子來訪問Android的Google日曆：

projection: array[1..4] of string=('_id','account_name','calendar_display_name','owner_account'); 

    Uri  :=TJnet_Uri.JavaClass.parse(StringToJString('content://com.android.calendar/events')); 
    managedCursor := SharedActivity.getContentResolver.query(Uri, projection, nil, nil, nil); 

而問題是最後的查詢必須接受投影爲的jstring。

我一直在努力，以及：

projection: array[1..4] of JString= (StringToJString('_id'),StringToJString('account_name'),StringToJString('calendar_display_name'),StringToJString('owner_account')); 

但它返回我下面的錯誤：

[DCC Error] Unit5.pas(46): E2250 There is no overloaded version of 'query' that can be called with these arguments 

什麼想法？

Answer 1

query函數的投影參數必須爲TJavaObjectArray<JString>，類似於JContentResolver類的查詢方法的簽名中所示。

function query(uri: Jnet_Uri; projection: TJavaObjectArray<JString>; selection: JString; selectionArgs: TJavaObjectArray<JString>; sortOrder: JString): JCursor; cdecl; overload; 
    function query(uri: Jnet_Uri; projection: TJavaObjectArray<JString>; selection: JString; selectionArgs: TJavaObjectArray<JString>; sortOrder: JString; cancellationSignal: JCancellationSignal): JCursor; cdecl; overload; 

所以，你可以在這條路上傳遞此參數

projection : TJavaObjectArray<JString>; 
begin 
    projection := TJavaObjectArray<JString>.Create(4); 
    projection.Items[0] := StringToJString('_id'); 
    projection.Items[1] := StringToJString('account_name'); 
    projection.Items[2] := StringToJString('calendar_display_name'); 
    projection.Items[3] := StringToJString('owner_account'); 

    Uri  :=TJnet_Uri.JavaClass.parse(StringToJString('content://com.android.calendar/events')); 
    SharedActivity.getContentResolver.query(Uri, projection, nil, nil, nil);