First steps with PaperJS. I realized this sketch and this video to describe the issue. As you can see in the video, drawing, for example, three items, and moving over them to select one and pressing the "d" key on keybord, it is possible to remove just the last added and selected item, but not the previous ones. If you start from the first or second item of the three added, the alert is not even triggered.
The wanted beaviour would be instead to select the event.item.selected (moving on it with the mouse) and remove just the selected one by clicking the "d" key on keyboard.
Thank you for your help
Your issue is that after removing the first path, your path variable no longer points to nothing.
So the next time you hit the delete key, you no longer know the selected path.
What you should do instead is storing the currently selected path into another variable and use it instead.
Here's a corrected sketch based on your code, demonstrating this.
Related
I have a list of items from where I drag an item and drop it into another list. I'm using copyArrayItem() method from Angular to not remove the item from the previous array.
I start dragging, the item is within the previous array: the placeholder from that item shows up.
Start dragging, placeholder shows up
I'm leaving the previous array: the placeholder/dragged item disappears (I want that the placeholder/dragged item stays) -> the start array has minus 1 items.
Placeholder disappears, what I don't want
I'm on the target array: a placeholder appears in a target array.
I'm dropping the item: item appears now in the start and target array.
After more research I've found an open issue about that problem:
https://github.com/angular/components/issues/13906
and there I've found suggestions from participants:
https://stackblitz.com/edit/angular-krmecd?file=src%2Fapp%2Fapp.component.ts
This example with workaround helped me to solve this problem:
https://stackblitz.com/edit/angular-o8exzv-jauhhi?file=src%2Fapp%2Fcdk-drag-drop-connected-sorting-example.html
Maybe this information will be useful for someone.
I'd like to run a procedure--once--whenever the selected item in a ListView changes. The obvious choice would be OnSelectItem, but it's called twice when the user moves from one selected item to another (using mouse or arrow keys). Similarly, OnChange is called three times when moving between items.
Is there an event generated only once under these conditions? OnClick is generated once, but doesn't cover moving between items using arrow keys, etc.
You can do it like this using OnSelectItem.
Remember the last selected item.
When the OnSelectItem fires, check if the current selected item differs from the one you remembered.
If so, perform your task, and make a note of the new selected item.
I seem to have a mental block with this one.
I need to save recent changes to a Record. I am doing it OK with buttons for "New" "Edit" "Post" "Next" etc but when a user double-clicks a DBGrid, it is now too late to make changes as the DBGrid selection has moved the database cursor to the selected record.
I can't use AutoUpdate as the data that may have been changed is not something the user would have directly entered, it is a value that is changing all the time.
I'll try to describe it better: While the user is reading a Test-page, a timer is counting down or up. When they click the "Next" or "Prior" buttons I can save the timer setting. But, if they Double-Click the DBGrid I have no way of first changing the current Record before the selection moves to the clicked-Record.
I tried using the
Procedure TForm1.tblTestOnBeforeScroll(...
begin
tblTest.Edit;
tblTest.FieldByName('TimerCt').AsInteger:=ClockCtr;
tblTest.Post;
end;
But, that crashed the database, not surprisingly, but I thought I would give it a try before asking here.
How do I deal with the current record? I do not want to disallow the double-click if possible as it seems nice and intuitive for the user.
I'm afraid that what you do on DBGrid is a wrong in concept action.
Key point is DBGrid is a data aware control. So everything you do on it must based on it's datasource then it's dataset.
There is a DblClick event on TDBgrid. But still you have to check it's dataset to see what record is active.
The code you shown above clearly lead you to an endless loop.
When you doing a scroll, the dbgrid will call OnBeforeScroll event, moving the active record
and call OnAfterScroll. Your OnBeforeScroll code does an data update. Then dbgrid abort its operation cause of data change. Then after data update, it try to scroll again, and the data change happen again. Endless loop happen here.
best regard
Apologies in advance if I'm misunderstanding you, but it seems to me that either the premise of your question is wrong or there is something relevant you haven't told us about what you're doing. Please try the following:
If you don't have one already, please temporarily add a DBNavigator to your form and connect it to the same DataSource as your DBGrid. The point of doing this is so that you can more clearly see what's going on.
Then, in your DBGrid's Options, set dgEditing to True.
Finally, comment out or disable your BeforeScroll handler, save and run your program.
Now, click once in some cell in your DBGrid that contains a value which it's ok to change. Click it a second time so that it selects the value in the cell rather than the cell per se.
Make some change to the cell value, but do nothing else for the time being. You should notice that a) the current record indicator of the DBGrid has changed from a black triangle to an I-Beam graphic, like ][ and b) that the tick and cross buttons of the DBNavigator are now enabled.
Now, without doing anything else on the form, click in another row of the DBGrid. You should find that a) the change to what was the current record in step 5 has been saved and b) the current row indicator reverts to the black triangle and the DBNav's tick and cross buttons are disabled.
(If you don't get the behaviour I've just described, create a minimal new project and try that instead, as some other change you've made in your existing project may be interfering with it).
What I've described in 5 & 6 is the default behaviour of a DBGrid and insofar as I understand your q, that seems to be the behaviour you're trying to achieve. If that's not the behaviour you want, please explain exactly how what you do want differs. It's not clear to me where the user double-clicking on the grid comes into your q, except that that action may move the dataset's cursor (if the dbl-click is on a different row than the current one), but as the default DBGrid behaviour will save changes to the current row before it moves the dataset's cursor, it will do what you seem to want automatically.
Btw, what "AutoUpdate" do you mean? Did you mean TDataSource's AutoEdit property?
Default behavior of a tableview is to highlight in blue a selected row.
I have an edit/delete (not sure on the wording yet) button that puts the table in edit mode, showing the red delete circles.
I'm unsure about how or even whether to let the user edit the text of a row. (Although until now "whether" hasn't even crossed my mind.)
Is it better to let the user add and delete items, or should I include an edit function?
If I should include an edit function, should it be triggered by the same edit function that makes the delete circles appear, or should editing be enabled by another button (limited space for buttons) or even a fancy gesture?
I would say limiting the user to add and delete but not edit would depend on your use case and what a row of your table represents. If it's a small piece of information (say a name) then it may be more sensible to just delete the wrong one and enter a new one rather than edit. If the row represents some larger object, then edit would probably be a good idea. What I would recommend to get that done, is pushing to some detail view controller when the row is tapped which would have it's own edit state and allows the user to change whatever they want with that object (like how the contacts app works).
When you select multiple nodes of a JvTreeView, and then try to drag these nodes, the JvTreeView selects the node you clicked to drag, rather than initiating dragging all the selected nodes. You end up dragging only this single node.
Is it possible to drag multiple nodes in a JvTreeView? I am using Delphi 2007.
UPDATE: Oddly enough, if I hold down CTRL+SHIFT when dragging the items, I can successfully drag them all. Any ideas?
Suppose MultiSelectStyle is the default [msControlSelect], then the answer to your question is 'you don't release the control key when you're selecting the last item and beginning dragging'.
The culprit is in TJvTreeView.WMLButtonDown in JvComCtrls.pas. Code there tests if 'Ctrl' is pressed when the TreeView is MultiSelect, and clears all items and selects the clicked item if 'Ctrl' is not pressed. It should instead test if the clicked item is already selected and do nothing if it is.
You can see the broken behavior without dragging. Multi select a few items and then click a selected item with the mouse. The VCL TreeView do not select or de-select anything, while the JVTreeView, instead, de-selects all items and selects the clicked one.
Yes absolutely, I do it all the time.
Of course Multi-Select needs to be True and you may need to have a look at the TTreeView's MultiSelectStyle. That controls what type of nodes can be selected at the same time. For example if msSiblingOnly is set to true, you can only select sibblings.
Are you using dmAutomatic or dmManual. If the latter, it could be that you are doing something in the OnMouse* events that is negating the multi-selection you made earlier.