Real simple issue: I want to know if the CTRL key is pressed when the user sorts a ListView. If the CTRL key is down, then I want to extend the number of columns in the sort. if the CTRL key is up, then I just sort on the selected column (no, this isn't a DataGrid, just a ListView with a set of header controls).
I found this, but it doesn't work (Window.Current == null) in the constructor.
public PositionView(PositionViewModel positionViewModel)
{
this.DataContext = positionViewModel;
Window.Current.CoreWindow.KeyDown += this.CoreWindow_KeyDown;
this.InitializeComponent();
}
private void CoreWindow_KeyDown(Windows.UI.Core.CoreWindow sender, Windows.UI.Core.KeyEventArgs args)
{
throw new NotImplementedException();
}
I don't want to get notified of a keyboard event just from the control with the input focus, I want notification for the entire application.
You can try this way:
static bool IsKeyDown(VirtualKey key)
{
return InputKeyboardSource
.GetKeyStateForCurrentThread(key)
.HasFlag(CoreVirtualKeyStates.Down);
}
Related
I'm using barteksc pdf viewer library to load pdf in my application.
pdfView = findViewById(R.id.pdfView);
pdfView.fromAsset(getResources().getString(R.string.pdfname))
.enableDoubletap(true)
.enableSwipe(true)
.defaultPage(pageNumber)
.onPageChange(mainreading.this)
.pageFitPolicy(FitPolicy.WIDTH)
.pageFling(true)
.linkHandler(null)
.enableAnnotationRendering(true)
.swipeHorizontal(true)
.scrollHandle(new DefaultScrollHandlenew(mainreading.this))
.enableAntialiasing(true)
.load();
}
I want pdf to start scroll automatically when user click the button of volume up and down buttons to start stop. I tried with below code while wrapping it in the handler with handler.performClick(); but it shows blank screen while scrolling up and down.
scrollbutton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
pdfView.scrollTo(0, pdfView.getScrollY() + 24);
}
});
Example :
https://play.google.com/store/apps/details?id=com.emptysheet.pdfreader_autoscroll&hl=en&gl=US
I want to make as like this. Can anyone help please.
Also tried with this. But it shows blank page after some scrolls.
#Override
public boolean dispatchKeyEvent(KeyEvent event) {
int action = event.getAction();
int keyCode = event.getKeyCode();
switch (keyCode) {
case KeyEvent.KEYCODE_VOLUME_UP:
if (action == KeyEvent.ACTION_DOWN) {
pdfView.scrollTo(0, pdfView.getScrollY() -24);
}
return true;
case KeyEvent.KEYCODE_VOLUME_DOWN:
if (action == KeyEvent.ACTION_DOWN) {
pdfView.scrollTo(0, pdfView.getScrollY() + 24);
}
return true;
default:
return super.dispatchKeyEvent(event);
}
}
You can simply use this PDF viewer from github.
It's based on the same 'barsteksc' pdf viewer with the feature to jump to any pages.
It's MagicalPdfViewer and you can use 'jumpTo(pageNo)' method to simply jump to the specific page. It also gives you the option to animate to the specific page with the same method, just pass 'true' as the 2nd parameter.
Moreover, if you pass the values like '-1' and 'bigger than pageNo', It will automatically scroll to the 0 & last page respectively.
Give it a try & let me know if you got what you wanted.
I'm making a synth for school, and I want to be able to play a note for the amount of time the key is being pressed on. I already know that syscall 30 will give me system time, but I don't know how to know when the key is no longer pressed on.
Here's some relevant code from the Keyboard and Display Simulator plug-in tool for MARS & RARS (the RISC V version of MARS):
private class KeyboardKeyListener implements KeyListener {
public void keyTyped(KeyEvent e) {
int updatedReceiverControl = readyBitSet(RECEIVER_CONTROL);
updateMMIOControlAndData(RECEIVER_CONTROL, updatedReceiverControl, RECEIVER_DATA, e.getKeyChar() & 0x00000ff);
if (updatedReceiverControl != 1) {
InterruptController.registerExternalInterrupt(EXTERNAL_INTERRUPT_KEYBOARD);
}
}
/* Ignore key pressed event from the text field. */
public void keyPressed(KeyEvent e) {
}
/* Ignore key released event from the text field. */
public void keyReleased(KeyEvent e) {
}
}
You could alter this code to do something in the lower level events handlers: keyPressed and keyReleased — instead the higher level event: keyTyped.
The idea is that you could supply key code data rather than character data, either at some new MMIO register location -or- hijack the existing receiver data and control locations for key code data instead of character data.
I have several Text-boxes on the form. I want to type in one of them just in Persian. I found this code, but the first character is typed in English.
private void txtBox_Enter(object sender, EventArgs e)
{
YourMethod();
}
private InputLanguage GetFarsiLanguage()
{
//Enumerate through InstalledInputLanguages which contains
//all the keyboard layout you’ve installed in your windows.
foreach (InputLanguage lang in InputLanguage.InstalledInputLanguages)
{
if (lang.LayoutName.ToLower() == "farsi" || lang.LayoutName.ToLower() == "persian")
return lang;
}
return null;
}
public void YourMethod()
{
InputLanguage lang = GetFarsiLanguage();
if (lang == null)
throw new NotSupportedException("Farsi Language keyboard is not installed.");
//Set the current language of the system to
//the InputLanguage instance you need.
InputLanguage.CurrentInputLanguage = lang;
}
private void txtBox_TextChanged(object sender, EventArgs e)
{
YourMethod();
}
From what you have described it sounds like the 'Enter' event isn't working for whatever reason. The txtBox_TextChanged event method will execute only after the first character has been entered. Hence the language will change after the first character.
To test this theory enter the following in the txtBox_Enter event method:
txtbox.ForeColor = Color.Red;
It will change the textbox red if the 'Enter' event executes.
If you can't get the 'Enter' event to work then try using the 'PreviewKeyDown' event.
I have 2 Telerik's rad grids. First one is master and second one is detail. I can delete rows from both grids independently by pressing "Delete" button on toolbar above each grid. I also have "Refresh" buttons in toolbar of both grids.
The problem is with detail grid. When I delete item(s) the grid doesn't refresh. Calling Rebind method doesn't help. The only thing that helps is to press "Refresh" button in toolbar of master grid and select the row in master grid by mouse that was previously selected. After that I can see refreshed detail grid.
So, I don't need to press "Refresh" button in toolbar of master grid and select the row in master grid by mouse. I can refresh the master grid programmatically and only want to reselect the item that was originally selected also programmatically. I've tried this:
item.Selected = true;
But, it only visually selects the item in master grid and doesn't refresh the detail grid.
So, how to select the item in master grid programmatically in order to get the same effect as selecting it by mouse?
Thank you in advance.
I've just realised that your probably using different DataSource for both grids, but pointing to the same database, right? My example below uses the same datasource for both grids. However I made on a detail view versus a normal view by making some columns not visible. Maybe this strategy could fix your issue?
My first thought was to try implement the SelectionChanged event, or if not that, the SelectionChanging event. Put a refresh in there you see. But I didn't end up doing it that way.
I wrote a small program as below. It saves the edits to disk with any row change as long as its not a remove (I had trouble saving remove edits when the button was clicked it gave a null pointer exception on the remove command). It also saves changes just before closing the program (so that any delete rows are also saved then). I did find that the deleteOne and deleteTwo buttons (that delete from the first or second grid, respectively) do in fact cause the deletion to occur in both grids. So a possibility is you could use the radGridView1.Rows.Remove(row) or RemoveAt(i) command if that works in your situation?
Another possibility is that if refresh isn't working you could set the DataSource to null and then set it to the data source again, after deleting the row. This is a bit drastic but if it's the only thing that works? I'm talking about the data source for both grids.
My code is below:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using Telerik.WinControls;
using Telerik.WinControls.Data;
using Telerik.WinControls.UI;
namespace RadControlsWinFormsApp1
{
public partial class RadForm1 : Telerik.WinControls.UI.RadForm
{
public RadForm1()
{
InitializeComponent();
}
private void RadForm1_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'testdbDataSet.Customers' table. You can move, or remove it, as needed.
this.customersTableAdapter.Fill(this.testdbDataSet.Customers);
radGridView1.Columns["Address"].IsVisible = false;
}
private void radGridView1_RowsChanged(object sender, Telerik.WinControls.UI.GridViewCollectionChangedEventArgs e)
{
// if removing don't update, because if my delete button is pressed this
// will otherwise cause all sorts of problems and freezes the grid
if (e.Action != NotifyCollectionChangedAction.Remove)
{
try
{
customersTableAdapter.Update(testdbDataSet);
}
catch (DBConcurrencyException ex)
{
// unable to save right now, don't worry about it
}
}
radGridView2.Refresh();
}
private void butDeleteOne_Click(object sender, EventArgs e)
{
bool haveRemoved = false;
for (int i = 0; i < radGridView1.Rows.Count && !haveRemoved; ++i)
{
GridViewRowInfo row = radGridView1.Rows[i];
if (row.IsSelected)
{
haveRemoved = true;
radGridView1.Rows.RemoveAt(i);
}
}
}
private void butDeleteTwo_Click(object sender, EventArgs e)
{
bool haveRemoved = false;
for (int i = 0; i < radGridView2.Rows.Count && !haveRemoved; ++i)
{
GridViewRowInfo row = radGridView2.Rows[i];
if (row.IsSelected)
{
haveRemoved = true;
radGridView2.Rows.RemoveAt(i);
}
}
}
private void radGridView2_RowsChanged(object sender, GridViewCollectionChangedEventArgs e)
{
// if removing don't update, because if my delete button is pressed this
// will otherwise cause all sorts of problems and freezes the grid
if (e.Action != NotifyCollectionChangedAction.Remove)
{
try
{
customersTableAdapter.Update(testdbDataSet);
}
catch (DBConcurrencyException ex)
{
// unable to save right now, don't worry about it
}
}
radGridView1.Refresh();
}
private void RadForm1_FormClosing(object sender, FormClosingEventArgs e)
{
// ensure all data is saved back into database on close
customersTableAdapter.Update(testdbDataSet);
}
//private void radGridView1_CellEndEdit(object sender, Telerik.WinControls.UI.GridViewCellEventArgs e)
//{
//}
}
}
Is there any way to prevent the change of a tab in TabControl in Silverlight 4?
A simple case is when I've got a form with some data, and I want to ask the user if he/she wants to save this data before actually changing the tab.
I've seen code examples on how to do this in WPF, but not in Silverlight.
What can I do to stop the tab from changing?
Bind SelectedIndex to a property on your data context.
<sdk:TabControl SelectedIndex="{Binding SelectedIndex, Mode=TwoWay}">
<sdk:TabItem Header="TabItem">
<Grid Background="#FFE5E5E5"/>
</sdk:TabItem>
<sdk:TabItem Header="TabItem">
<Grid Background="#FFE5E5E5"/>
</sdk:TabItem>
</sdk:TabControl>
In the SET accessor, write your code to check whether the user really wants to do what they're trying to do.
public class Context : INotifyPropertyChanged
{
int _SelectedIndex = 0;
public int SelectedIndex
{
get
{
return _SelectedIndex;
}
set
{
MessageBoxResult result = MessageBox.Show("Do you want to save?", "Really?", MessageBoxButton.OKCancel);
if (result == MessageBoxResult.OK)
{
_SelectedIndex = value;
}
RaisePropertyChanged("SelectedIndex");
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
}
Net effect is, if the user chooses 'cancel' on the dialogue the private variable is never changed - the PropertyChanged event fires, rebinding the selected index to the existing value.
Hope this is what you were trying to accomplish.
UPDATE (11/10/2012) - Alternate method (possibly for SL5?). Write code behind to tie into SelectionChanged event of your TabControl, reset the tab control's selected item property based on your test.
private void TabControl_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
{
if (e.RemovedItems.Count > 0)
{
MessageBoxResult result = MessageBox.Show("Do you want to save?", "Really?", MessageBoxButton.OKCancel);
if (result != MessageBoxResult.OK)
{
((TabControl)sender).SelectionChanged -= new SelectionChangedEventHandler(TabControl_SelectionChanged);
((TabControl)sender).SelectedItem = e.RemovedItems[0];
((TabControl)sender).SelectionChanged += new SelectionChangedEventHandler(TabControl_SelectionChanged);
}
}
}