![]() The CursorAdapter will take care of recycling views NewView – Called when the ListView requires a new view toĭisplay. Given a working SQLite database, you only need to override two methods toīindView – Given a view, update it to display the data in the Subclassing BaseAdapter because it does not override GetView, The CursorAdapter implementation is very different from Gives you complete control over the creation and layout of each row ![]() SimpleCursorAdapter for displaying data from SQLite, but it also Subclassing CursorAdapterĪ CursorAdapter subclass has the same performance benefits as the Values to display controls, it does not allow you to change otherĪspects of the row layout (for example, showing/hiding controls orĬhanging properties). The main limitation is that it can only bind column SimpleCursorAdapter is a fast and simple way to display SQLite data ListView.Adapter = new SimpleCursorAdapter (this, 1, cursor, The complete VegetableDatabase class is shown here: class VegetableDatabase : SQLiteOpenHelper ![]() ![]() The code in SimpleCursorTableAdapter/VegetableDatabase.csĬontains the code and SQL to create a table and populate it with some data. To demonstrate cursor adapters requires a simple SQLite database In a Cursor object and then describe how to create and The consuming code must define an SQL query (for example, hiding/showing controls or changing their properties).Ĭursor adapters provide a high-performance way to scroll through long lists When you need more control over the binding of data values to layout controls Simply provide the required parameters (such as a cursor and layout information) in the constructor and then assign to a ListView.ĬursorAdapter – A base class that you can inherit from SimpleCursorAdapter – Similar to an ArrayAdapter because it can be used without subclassing. (Not dragging by the way, since that ends with a event).Android provides adapter classes specifically to display data from an SQLite This way you bind your callback to a tag that is handled after all those actions mentioned in the quote above, so you will see the cursor to be at position 0.ĭo keep in mind that this affects all clicks, including double click, triple click, control-click. To do this you can add a bindtag after the class and bind to that: e.bindtags(((str(e)), "TEntry", "post-click", ".", "all")) However, you can add an event after the default event has been handled. Because this is the order in which the events are handled, you never see the cursor at location 0. So even though you did put the cursor at position 0, the default Entry event for the mouse button is to change the location of the cursor to where you clicked. Dragging with mouse button 1 strokes out a selection between the insertion cursor and the character under the mouse. The default event from the ttk Entry inherits from the standard Tkinter Entry which, according to the manual, isĬlicking mouse button 1 positions the insertion cursor just before the character underneath the mouse cursor, sets the input focus to this widget, and clears any selection in the widget. When you click the widget, first your on_click function is called which puts the cursor at the start, then the default event for a ttk Entry box is called. Now, when you do e.bind("", on_click), you bind the on_click function to the widget e. is the widget's Toplevel or Tk instance and all is a tag that can be bound to that all widgets have. !entry is the current widget e, TEntry is the ttk Entry class. To see what these are you can print(e.bindtags()) which prints ('.!entry', 'TEntry', '.', 'all') This is due to the order in which events are handled in Tkinter.įor a detailed explanation read this answer, but in short events are handled in the order of the bindtags.
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