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调整ScroldComposite中扩展栏SWT的大小

Java问题
2022-01-01

Resize expandbar SWT in ScrolledComposite(调整ScroldComposite中扩展栏SWT的大小)

本文介绍了调整ScroldComposite中扩展栏SWT的大小的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在构建一个java SWT独立应用程序，在滚动组合中有一个展开栏。在某些情况下，我将向其中一个组件添加一个字段。因此，项目的大小将会增加。首先，我销毁扩展栏中的所有当前项目： 

 public void closeAll(){
    for(int a = bar.getItemCount()-1; a>=0; a--){
        bar.getItem(a).getControl().dispose();
        bar.getItem(a).dispose();
    }
}

然后我将把它们全部再读一遍(我将组合存储在其他地方)。我重新计算每一项的高度：

for(int a = 0; a<bar.getItemCount(); a++){
        bar.getItem(a).setHeight(bar.getItem(a).getControl().computeSize(SWT.DEFAULT, SWT.DEFAULT).y);

    }
当我执行所有这些操作时，滚动的组合将不会进一步向下滚动(展开栏的一部分现在位于ScrolledComposite的工作区之外)。

当我调整窗口本身的大小时，所有问题都解决了。那么，我如何才能在没有代码的情况下强制执行此通常与调整窗口大小相关的更新？

提前感谢大家！

//编辑

我已经添加了我所说的类：

public class InputPanel extends Panel implements Refresh{

private Editor parent;
private ExpandBar expandBar;

private ArrayList<InputBlock> blocks;
public ScrolledComposite scroll;



public InputPanel(Editor parent, Composite panel) {
    super(panel);
    this.parent = parent;
    setGridLayout(0,0,1);
    blocks = new ArrayList<InputBlock>();
    init();
}
private void init(){
    //two pannels first button pannel
    Panel buttonPanel = new Panel(new Composite(panel, SWT.BORDER));
    buttonPanel.setGridLayout(0, 0, 3);
    buttonPanel.fillGridData();

    Composite barComp = new Composite(panel, SWT.BORDER);

    barComp.setLayout(new FillLayout());
    GridData data1 = new GridData();
    data1.grabExcessHorizontalSpace = true;
    data1.horizontalAlignment = SWT.FILL;
    data1.verticalAlignment = SWT.FILL;
    barComp.setLayoutData(data1);

    scroll = new ScrolledComposite(barComp, SWT.V_SCROLL);
    expandBar = new ExpandBar(scroll, SWT.None);
    GridData data = new GridData();
    data.grabExcessHorizontalSpace = true;
    data.grabExcessVerticalSpace = true;
    data.horizontalAlignment = SWT.FILL;
    data.verticalAlignment = SWT.TOP;

    scroll.setContent(expandBar);
    scroll.setExpandVertical(true);
    scroll.setExpandHorizontal(true);
    scroll.setAlwaysShowScrollBars(true);
    for(int a = 0; a<Main.database.size(); a++){
        Composite composite = new Composite(expandBar, SWT.BORDER);
        blocks.add(new InputBlock(this, composite, Main.database.get(a)));
        addItem(composite, Main.database.get(a).name);
    }
    refreshHeights();
    scroll.setMinSize(expandBar.computeSize(SWT.DEFAULT, SWT.DEFAULT));
    scroll.layout(true);
}
public void addItem(Composite composite, String tabName){
    ExpandItem expandItem = new ExpandItem(expandBar, SWT.None);
    expandItem.setText(tabName);
    expandItem.setControl(composite);
    expandItem.setExpanded(true);
    composite.setVisible(true);
}
public void refreshHeights(){
    for(int a = 0; a<expandBar.getItemCount(); a++){
        expandBar.getItem(a).setHeight(expandBar.getItem(a).getControl().computeSize(SWT.DEFAULT, SWT.DEFAULT).y);
    }

}
public void closeAll(){
    ExpandItem[] items = expandBar.getItems();
    System.out.println(items.length);

    for(int a = items.length-1; a>=0; a--){
        items[a].getControl().dispose();
        items[a].dispose();
    }
}


public void refresh(){
    closeAll();
    blocks = new ArrayList<InputBlock>();
    for(int a = 0; a<Main.database.size(); a++){
        Composite composite = new Composite(expandBar, SWT.BORDER);
        blocks.add(new InputBlock(this, composite, Main.database.get(a)));
        addItem(composite, Main.database.get(a).name);
    }
    refreshHeights();
    scroll.setMinSize(expandBar.computeSize(SWT.DEFAULT, SWT.DEFAULT));
    scroll.layout(true);
}

public Editor getParent(){
    return parent;
}


public void setEditorMenu(boolean show){
    for(int a = 0; a<blocks.size(); a++){
        blocks.get(a).setEditorMenu(show);
    }
}



public ArrayList<InputBlock> getBlocks(){
    return blocks;
}
public boolean setValue(DatabaseField field, String value){
    value = value.trim();
    for(int a = 0; a<blocks.size(); a++){
        if(blocks.get(a).setValue(field, value)){
            return true;
        }
    }
    return false;
}

}

我试着做一个例子，但是这个例子开箱即用。我看不出有什么不同。InputBlock是保存有关复合中所需字段的数据的类，如果调用它们将生成复合。

包含ScrolledComposite的复合体当前处于SashForm状态，我不知道这是否会有什么不同？

我收到此错误(仅在Linux上)，但不是在我尝试的示例中：

SWT:12455): Gtk-CRITICAL **: IA__gtk_widget_map: assertion `gtk_widget_get_visible (widget)' failed
(SWT:12455): Gtk-CRITICAL **: IA__gtk_widget_map: assertion `gtk_widget_get_visible (widget)' failed
(SWT:12455): Gtk-CRITICAL **: IA__gtk_widget_map: assertion `gtk_widget_get_visible (widget)' failed

更新

我把我的问题做了一个更好的例子。此代码正在运行并为我生成相同的错误：

(SWT:6765): Gtk-CRITICAL **: IA__gtk_widget_map: assertion `gtk_widget_get_visible (widget)' failed

我使用过以下代码：

import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CTabFolder;
import org.eclipse.swt.custom.CTabItem;
import org.eclipse.swt.custom.SashForm;
import org.eclipse.swt.custom.ScrolledComposite;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.ExpandBar;
import org.eclipse.swt.widgets.ExpandItem;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;


 public class ExpandBarExample implements SelectionListener{



public static void main(String[] args){
    Display display = new Display();
    Shell shell = new Shell(display);
    new ExpandBarExample(shell);
    shell.setMaximized(true);
    shell.setLayout(new FillLayout());
    shell.open();

    while(!shell.isDisposed()){
        if(!display.readAndDispatch()){
            display.sleep();
        }
    }
    display.dispose();
}

private  ExpandBar bar;
private  ScrolledComposite scroll;
private  Composite composite;
private SashForm sash;
private CTabFolder folder;
private Button button;

public ExpandBarExample(Composite composite){
    this.composite = composite;

    init();
}
public void init(){


    composite.setLayout(new FillLayout());
    sash = new SashForm(composite, SWT.VERTICAL);

    folder = new CTabFolder(sash, SWT.None);


    scroll = new ScrolledComposite(folder, SWT.V_SCROLL);
    GridData data = new GridData();
    data.grabExcessHorizontalSpace = true;
    data.grabExcessVerticalSpace = true;

    bar = new ExpandBar(scroll, SWT.NONE);
    scroll.setContent(bar);
    scroll.setExpandVertical(true);
    scroll.setExpandHorizontal(true);
    scroll.setAlwaysShowScrollBars(true);



    CTabItem tab = new CTabItem(folder, SWT.None);
    tab.setControl(scroll);
    tab.setText("TEST");

    Composite sashFill = new Composite(sash, SWT.BORDER);
    sashFill.setLayout(new FillLayout());
    button = new Button(sashFill, SWT.PUSH);
    button.addSelectionListener(this);
    button.setText("Add block");

    sash.setWeights(new int[]{3,1});

    for(int a = 0; a<10; a++){
        Composite composite = new Composite(bar, SWT.BORDER);

        composite.setLayout(new GridLayout(2, false));

        for(int b = 0; b<10; b++){
            Label label = new Label(composite, SWT.BORDER);
            label.setText("TEST");
        }

        addItem(composite, "Item " + a);
    }
    computeHeights();
    scroll.setMinSize(bar.computeSize(SWT.DEFAULT, SWT.DEFAULT));
    scroll.layout(true);



    //delete old panels
    removeAll();
    //trying to add more panels

    for(int a = 0; a<10; a++){
        Composite composite = new Composite(bar, SWT.BORDER);


        composite.setLayout(new GridLayout(2, false));

        for(int b = 0; b<20; b++){
            Label label = new Label(composite, SWT.BORDER);
            label.setText("TEST");
        }

        addItem(composite, "Item " + a);
    }


    computeHeights();
    scroll.setMinSize(bar.computeSize(SWT.DEFAULT, SWT.DEFAULT));
    scroll.layout(true);

}
public void refresh(){

}
public void removeAll(){
    ExpandItem[] items = bar.getItems();
    System.out.println(items.length);

    for(int a = items.length-1; a>=0; a--){
        items[a].getControl().dispose();
        items[a].dispose();
    }
}
public void addItem(Composite composite, String tabName){
    ExpandItem expandItem = new ExpandItem(bar, SWT.None);
    expandItem.setText(tabName);
    expandItem.setControl(composite);
    expandItem.setExpanded(true);
}
public void computeHeights(){
    for(int a = 0; a<bar.getItemCount(); a++){
        bar.getItem(a).setHeight(bar.getItem(a).getControl().computeSize(SWT.DEFAULT, SWT.DEFAULT).y);
    }
}
@Override
public void widgetSelected(SelectionEvent e) {
    if(e.getSource() == button){
        Composite comp = new Composite(bar, SWT.BORDER);
        comp.setLayout(new GridLayout(2, false));
        for(int a = 0; a<10; a++){
            Label label = new Label(comp, SWT.BORDER);
            label.setText("TEST");
        }
        comp.layout(true);
        addItem(comp, "ADDED");
        computeHeights();

        scroll.setMinSize(bar.computeSize(SWT.DEFAULT, SWT.DEFAULT, true));

        scroll.layout(true, true);
    }

}
@Override
public void widgetDefaultSelected(SelectionEvent e) {
    // TODO Auto-generated method stub

}

}

我曾尝试在Ubuntu和openSUSE上运行此程序，两者都给出了相同的GTK错误。我希望有人能帮助我！

推荐答案

好的，我找到了解决办法。这并不是真正修复问题的解决方案，而是避免问题的方法。

您的问题似乎是由展开ExpandItem时出现的延迟引起的。因此，更新minSize的代码使用未展开的大小。在设置minSize之前添加延迟可以解决您的问题。尝试调整延迟值，但300ms似乎工作正常，并不会真正影响可用性：

public static void main(String[] args)
{
    Display display = new Display();
    Shell shell = new Shell(display);
    new ExpandBarExample(shell);
    shell.setMaximized(true);
    shell.setLayout(new FillLayout());
    shell.open();

    while (!shell.isDisposed())
    {
        if (!display.readAndDispatch())
        {
            display.sleep();
        }
    }
    display.dispose();
}

private ExpandBar           bar;
private ScrolledComposite   scroll;
private Composite           composite;
private SashForm            sash;
private CTabFolder          folder;
private Button              button;

public ExpandBarExample(Composite composite)
{
    this.composite = composite;

    init();
}

public void init()
{

    composite.setLayout(new FillLayout());
    sash = new SashForm(composite, SWT.VERTICAL);

    folder = new CTabFolder(sash, SWT.None);

    scroll = new ScrolledComposite(folder, SWT.V_SCROLL);
    GridData data = new GridData();
    data.grabExcessHorizontalSpace = true;
    data.grabExcessVerticalSpace = true;

    bar = new ExpandBar(scroll, SWT.NONE);
    scroll.setContent(bar);
    scroll.setExpandVertical(true);
    scroll.setExpandHorizontal(true);
    scroll.setAlwaysShowScrollBars(true);

    CTabItem tab = new CTabItem(folder, SWT.None);
    tab.setControl(scroll);
    tab.setText("TEST");

    Composite sashFill = new Composite(sash, SWT.BORDER);
    sashFill.setLayout(new FillLayout());
    button = new Button(sashFill, SWT.PUSH);
    button.addListener(SWT.Selection, new Listener()
    {
        @Override
        public void handleEvent(Event arg0)
        {
            Composite comp = new Composite(bar, SWT.BORDER);
            comp.setLayout(new GridLayout(2, false));
            for (int a = 0; a < 10; a++)
            {
                Label label = new Label(comp, SWT.BORDER);
                label.setText("TEST");
            }
            comp.layout(true);
            addItem(comp, "ADDED");

            scroll.setMinSize(bar.computeSize(SWT.DEFAULT, SWT.DEFAULT, true));
            scroll.layout(true, true);
        }
    });
    button.setText("Add block");

    sash.setWeights(new int[] { 3, 1 });

    scroll.setMinSize(bar.computeSize(SWT.DEFAULT, SWT.DEFAULT));
    scroll.layout(true);
}

public void refresh()
{

}

public void removeAll()
{
    ExpandItem[] items = bar.getItems();
    System.out.println(items.length);

    for (int a = items.length - 1; a >= 0; a--)
    {
        items[a].getControl().dispose();
        items[a].dispose();
    }
}

public void addItem(Composite composite, String tabName)
{
    final ExpandItem expandItem = new ExpandItem(bar, SWT.None);
    expandItem.setText(tabName);
    expandItem.setControl(composite);
    expandItem.setExpanded(true);
    expandItem.setHeight(composite.computeSize(SWT.DEFAULT, SWT.DEFAULT).y);

    Display.getDefault().timerExec(300, new Runnable()
    {
        @Override
        public void run()
        {
            scroll.setMinSize(bar.computeSize(SWT.DEFAULT, SWT.DEFAULT, true));
            scroll.layout(true, true);
        }
    });
}

这篇关于调整ScroldComposite中扩展栏SWT的大小的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！

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