我需要使用stderr滚动QT图表，为此，我使用可以拖动的InputStream和OutputStream创建了我自己的自定义scrollbar。< / p>
当我尝试使用scrollbar和Rectangle方法滚动图表时，我无法将MouseArea ScrollRight与ScrollLeft内容关联/绑定X.以下是代码：
ScrollBar 1）如何将X与ChartView内容import QtQuick 2.6
import QtQuick.Window 2.2
import QtQuick.Controls 2.2
import QtCharts 2.0
Window {
id: window
width: 640
height: 480
visible: true
ChartView {
id: chartview
width: parent.width
height: 300
LineSeries {
name: "LineSeries"
axisX: ValueAxis {
min: 0
max: 100
tickCount: 12
labelFormat: "%.0f"
}
axisY: ValueAxis {
min: 0
max: 70
tickCount: 5
labelFormat: "%.0f"
}
XYPoint { x: 0; y: 0.0 }
XYPoint { x: 1.1; y: 3.2 }
XYPoint { x: 1.9; y: 2.4 }
XYPoint { x: 2.1; y: 2.1 }
XYPoint { x: 2.9; y: 2.6 }
XYPoint { x: 3.4; y: 2.3 }
XYPoint { x: 200.1; y: 3.1 }
}
}
/* Rectangle base for horizontal scroll bar */
Rectangle{
id:rectHorScrollBase
width:parent.width
height:parent.height * 0.10
anchors.top:chartview.bottom
anchors.topMargin: (parent.height * 0.01)
color:"transparent"
visible: true
/* Rectangle indicating scroll path*/
Rectangle {
id:rectHorScrollPath
width: parent.width
height: parent.height
anchors.left:parent.left
radius: 2
color: "lightblue"
}
/* Actual scroll rectaangle which will be dragged */
Rectangle {
id: rectHorScroll
property var prevX : 0
anchors.top : parent.top
width: 50
height: parent.height
color: "green"
/* Mouser area to drag the rectangle and to move Chart */
MouseArea {
id:mouseAreaHorScroll
anchors.fill: parent
drag.target: parent
drag.minimumX: 0
drag.maximumX: chartview.width - width
drag.axis: Drag.XAxis
onReleased: {
console.log("x in Released ===",rectHorScroll.x)
rectHorScroll.prevX = rectHorScroll.x
}
}
onXChanged: {
// HOW TO HANDLE THE SCROLL BASED ON x ?
if(mouseAreaHorScroll.drag.active)
{
if(x > prevX)
{
chartview.scrollRight(x) // NOT WORKING
}
else
{
chartview.scrollLeft(x) //NOT WORKING
}
}
}
}
}
}
进行对比？
2）scrollBar X不应超出X轴的最大值和最小值。怎么做？
3）ChartView和X之间应该有同步。
答案 0 :(得分：1)
基本上它按预期工作。让我们分析一下你在做什么：
onXChanged: {
// HOW TO HANDLE THE SCROLL BASED ON x ?
if(mouseAreaHorScroll.drag.active)
{
if(x > prevX)
{
chartview.scrollRight(x) // NOT WORKING
}
else
{
chartview.scrollLeft(x) //NOT WORKING
}
}
}
首先，当scrollRight大于x时，你prevX - 效果很好。但是，对于scrollRight像素，您x会随着移动而增长，因此移动与滚动条的移动不是线性的。
scrollLeft确实（几乎）从未被调用过，这很明显：只有在prevX你x === 0 ( = prevX)时才会更新scrollLeft(0) - 这不是prevX移动。
我们需要应用的第一个更改是在处理程序的末尾更新onXChanged: {
// HOW TO HANDLE THE SCROLL BASED ON x ?
if(mouseAreaHorScroll.drag.active)
{
if(x > prevX)
{
chartview.scrollRight(x - prevX) // Only move the difference
}
else
{
chartview.scrollLeft(prevX - x) //Only move the difference
}
prevX = x // Update prevX
}
}
第二个变化是，我们只想移动自上次运行代码以来我们移动句柄。
因此解决方案如下：
axisX: ValueAxis {
min: rectHorScroll.x / (rectHorScrollBase.width - rectHorScroll.width) * 100
max: rectHorScroll.x / (rectHorScrollBase.width - rectHorScroll.width) * 100 + 100
tickCount: 12
labelFormat: "%.0f"
}
不是手动处理这些东西，而是调用这些函数，你也可以将轴的可见部分映射到x - 删除你的句柄并相应地更改axisX：
Slider在这里，您需要找到应用映射的正确方法，以获得正确的范围。
然后您还可以使用常规组件，例如import QtQuick 2.6
import QtQuick.Window 2.2
import QtQuick.Controls 2.0
import QtCharts 2.0
ApplicationWindow {
id: window
width: 640
height: 480
visible: true
ChartView {
id: chartview
width: parent.width
height: 300
LineSeries {
name: "LineSeries"
axisX: ValueAxis {
property real minValue: 0
property real maxValue: 200
property real range: 100
min: minValue + sb.position * (maxValue - minValue - range)
max: minValue + sb.position * (maxValue - minValue - range) + range
tickCount: 12
labelFormat: "%.0f"
}
axisY: ValueAxis {
min: 0
max: 70
tickCount: 5
labelFormat: "%.0f"
}
XYPoint { x: 0; y: 0.0 }
XYPoint { x: 1.1; y: 3.2 }
XYPoint { x: 1.9; y: 2.4 }
XYPoint { x: 2.1; y: 2.1 }
XYPoint { x: 2.9; y: 2.6 }
XYPoint { x: 3.4; y: 2.3 }
XYPoint { x: 200.1; y: 3.1 }
}
}
Slider {
id: sb
anchors {
bottom: parent.bottom
left: parent.left
right: parent.right
}
height: 30
}
}
来模拟滚动条：
class gestiontache extends JFrame{
JFrame f;
JPanel p1, p2, p3;
JTabbedPane tp;
JLabel l1, l2, l3,l4,l5;
JComboBox tf3categor;
JComboBox tf4Affiliation;
JComboBox tf5montant;
JTextField tf1, tf2;
JScrollPane sp1;
JButton savebtn, resetbtn, editbtn;
private static String FILE = "c:/temp/DocumentPdf.pdf";
private static Font catFont = new Font(Font.FontFamily.TIMES_ROMAN, 18,
Font.BOLD);
private static Font redFont = new Font(Font.FontFamily.TIMES_ROMAN, 12,
Font.NORMAL, BaseColor.RED);
private static Font subFont = new Font(Font.FontFamily.TIMES_ROMAN, 16,
Font.BOLD);
private static Font smallBold = new Font(Font.FontFamily.TIMES_ROMAN, 12,
Font.BOLD);
gestiontache() {
f = new JFrame("Form");
GridLayout lay1= new GridLayout(12, 2);
GridLayout lay2= new GridLayout(5, 2);
p1 = new JPanel(lay1);
p2 = new JPanel(lay2);
lay1.setHgap(5); //Cinq pixels d'espace entre les colonnes (H comme Horizontal)
lay1.setVgap(5); //Cinq pixels d'espace entre les lignes (V comme Vertical)
lay2.setHgap(5);
lay2.setVgap(5);
tp = new JTabbedPane();
l1 = new JLabel("Nom");
l2 = new JLabel("Prénom");
l3 = new JLabel("Catégorie");
l4 = new JLabel("Affiliation");
l5 = new JLabel("Montant à payer");
tf1 = new JTextField(12);
tf2 = new JTextField(12);
tf3categor = new JComboBox( new String[] { "Medecin", "Technicien", "Pharmacien","Autre" });
tf4Affiliation =new JComboBox( new String[] { "K", "T", "Sf","Gab","Toze","Med","Tat","Na","B","G","Si","Ga","Ke","Kr" });
tf5montant = new JComboBox( new String[] { "15 Dinars", "30 Dinars"});
savebtn = new JButton(" Ajouter ");
resetbtn = new JButton(" Annuler");
editbtn = new JButton(" Imprimer");
p1.add(l1);
p1.add(tf1);
p1.add(l2);
p1.add(tf2);
p1.add(l3);
p1.add(tf3categor);
p1.add(l4);
p1.add(tf4Affiliation);
p1.add(l5);
p1.add(tf5montant);
p1.add(savebtn);
p1.add(resetbtn);
p2.add(l1);
p2.add(tf1);
p2.add(l2);
p2.add(tf2);
p2.add(editbtn);
resetbtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
clear();
}
});
savebtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
String nom, prenom,categorie, affiliation, montant;
nom = tf1.getText();
prenom = tf2.getText();
categorie=(String) tf3categor.getSelectedItem();
affiliation=(String) tf4Affiliation.getSelectedItem();
montant=(String) tf5montant.getSelectedItem();
String url = "jdbc:mysql://localhost:3306/seminaire";
String userid = "root";
String password = "";
try {
Connection connection = DriverManager.getConnection(url,
userid, password);
Statement st = connection.createStatement();
if (nom != "" && prenom != ""&& categorie!= ""&& affiliation!= ""&& montant!= "") {
st.executeUpdate("insert into participant values('" + nom
+ "','" + prenom + "','" + categorie + "','"+affiliation+"','"+montant+"')");
JOptionPane.showMessageDialog(null,"Données insérées avec succès");
clear();
} else {
JOptionPane.showMessageDialog(null, "merci de saisir vos données");
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
});
editbtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
String nom, prenom,categorie, affiliation, montant;
nom = tf1.getText();
prenom = tf2.getText();
String url = "jdbc:mysql://localhost:3306/seminaire";
String userid = "root";
String password = "";
try {
Connection connection = DriverManager.getConnection(url,
userid, password);
Statement st = connection.createStatement();
if (nom != "" && prenom != "") {
ResultSet rs= st.executeQuery("SELECT * FROM participant
WHERE nom=nom && prenom=prenom");
while (rs.next())
{
String nm = rs.getString("nom");
String prnm = rs.getString("prenom");
String cat = rs.getString("categorie");
String afl=rs.getString("affiliation");
String mnt=rs.getString("montant");
// print the results
Document document = new Document();
try {
PdfWriter.getInstance(document, new FileOutputStream(FILE));
//open
document.open();
Paragraph p = new Paragraph();
p.add("Reçu");
p.setAlignment(Element.ALIGN_CENTER);
document.add(p);
Paragraph p2 = new Paragraph();
p2.add(nm); //no alignment
document.add(p2);
Font f = new Font();
f.setStyle(Font.BOLD);
f.setSize(8);
document.add(new Paragraph("This is my paragraph 3", f));
//close
document.close();
System.out.println("Done");
} catch (FileNotFoundException | DocumentException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
else {
JOptionPane.showMessageDialog(null, "merci de saisir vos données");
}
}
catch (Exception e)
{
System.err.println(e.getMessage());
}
}});
}
void dis() {
f.getContentPane().add(tp);
tp.addTab("Ajouter participant", p1);
tp.addTab("Imprimer attestation", p2);
f.setSize(500, 400);
f.setVisible(true);
f.setResizable(true);
}
void clear()
{
tf1.setText("");
tf2.setText("");
tf3categor.setSelectedItem("");
tf4Affiliation.setSelectedItem("");
tf5montant.setSelectedItem("");
}
public static void main(String z[]) {
gestiontache data = new gestiontache();
data.dis();
}
}