SWT中的布局之-----FormLayout(表格式布局)

表格式(FormLayout類) 表格式布局管理器,通過創建組件各個邊的距離來布局組件,和GridLayout一樣強大.

　　用GridLayout與FormLayout都可以實現相同的界面效果,但有時使用后者會更有效,而且不會像GridLayout因為容器大小變化而導致布局錯位.

　　使用marignWidth,marginHeight設置邊距(這兩個屬性,來設置容器的左邊距和上邊距(單位:像素))

　　使用FormData的構造函數(FormLayout也有自己的布局數據類,他的使用方法是new FormData()或new FormData(int width,int height))

　　FormAttachment類的用法

　　FormAttachment是在FormData下的,更進一步的布局數據類,它的用法主要體現在它不同的構造函數中.

FormLayout1.java

import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.FormLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class FormLayout1 {
    public static void main(String[] args) {
        final Display display = Display.getDefault();
        final Shell shell = new Shell();
        shell.setSize(327, 253);
        // ---------創建窗口中的其他界面組件-------------
        FormLayout formLayout = new FormLayout();
        formLayout.marginWidth = 100; // 左邊距，單位：像素
        formLayout.marginHeight = 50; // 上邊距
        shell.setLayout(formLayout);
        new Button(shell, SWT.NONE).setText("button1");
        // -----------------END------------------------
        shell.layout();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}

 

 

1.使用marginWidth,marginHeight設置邊距

這兩個屬性用來設置容器的左邊距和上邊距(單位:像素).下面給出一個具體的實例:

public class FormLayout1 {
    public static void main(String[] args) {
        final Display display = Display.getDefault();
        final Shell shell = new Shell();
        shell.setSize(327, 253);
        shell.setText("SWT Application");
        // ------------------新插入的界面核心代碼------------------------
        FormLayout formLayout = new FormLayout();  9         formLayout.marginWidth = 100; 10         formLayout.marginHeight = 50; 11  shell.setLayout(formLayout); 12         new Button(shell, SWT.NONE).setText("button1"); 13         // ------------------END---------------------------------------------
        shell.layout();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
    }
}

2.使用FormData的構造函數

FromLayout也有自己的布局數據類FormData,它的使用方法是:new FormData()或者new FormData(int width,int height)

public class FormData1 {
    public static void main(String[] args) {
        final Display display = Display.getDefault();
        final Shell shell = new Shell();
        shell.setSize(327, 253);
        shell.setText("SWT Application");
        // ------------------新插入的界面核心代碼------------------------
        shell.setLayout(new FormLayout());  9         // new FormData ()
        Button button1 = new Button(shell, SWT.NONE); 11         button1.setText("button1"); 12         FormData formData = new FormData(); 13  button1.setLayoutData(formData); 14         // new FormData (int width, int height)，單位：像素
        Button button2 = new Button(shell, SWT.NONE); 16         button2.setText("button2"); 17         FormData formData2 = new FormData(200, 50);// button2變成200長，50寬
 button2.setLayoutData(formData2); 19         // ------------------END---------------------------------------------
        shell.layout();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
    }
}

3.FormAttachment類的用法:

FromAttachment是在FormData下的,更進一步的布局數據類.它的用法體現在他不同的構造函數中.

 (1) new FormAttachment(int numerator,int offset)

　　button1的頂邊(fromData.top)離shell容器的空白邊距是shell容器總體空白長度的60%.

　　偏移的點數(points)為0,效果如下:

        //>>>>>>>>>>>>>>>華麗麗的分割線>>>>>>>>>>>>>>>>>>>>>>>>>>>>
        shell.setLayout(new FormLayout());
        new Text(shell, SWT.BORDER).setText("text1");
        //將button1應用FormData
        Button button1 = new Button(shell, SWT.NONE);
        button1.setText("button1");
        
        FormData formData = new FormData();
        formData.top = new FormAttachment(60, 0); // button1的頂端應用FormAttachment設置
        button1.setLayoutData(formData);
        
        //>>>>>>>>>>>>>>>華麗麗的分割線>>>>>>>>>>>>>>>>>>>>>>>>>>>>

如果改成了 formData.top = new FormAttachment(60, 30)

從圖中更以看出FormAttachment(60,30)是先按照FormAttachment(60,0)

的方式布局后,再下移動10個像素.這個地方有一個布局的次序.

new FormAttachment(int numerator)相當於new FormAttachment(int numerator,int offset)

當offset=0時,new FormAttachment(int numerator,int offset)相當於FormAttachmetn(int numerator,int denominator,int offset)當denominator(分母的意思)=100時,其中denominator是分母,例如FormAttachment(30,50,0)就是長度比例為30/50=60%,也就是和FormAttachment(60,0)的效果是一樣的.

(2) new FormAttachment(Control control,int offset,int alignment)

　　參數1是一個Control類,一般在使用的時候,都傳入一個組件(如文本框來做參數),應用此FormAttachment的組件將

　　依據參數1的contorl為基准來布局,offset為離control偏移量(單位:像素),alignment為對齊方式.

　　下面給出一個例子:

        //======================華麗麗的分割線===========================
        shell.setLayout(new FormLayout());
        Text text1 = new Text(shell, SWT.BORDER);
        text1.setLayoutData(new FormData(100, 50));
        //定義並設置FormData
        FormData formData = new FormData();
        //以text1為基准偏移50像素
        FormAttachment formAttachment = new FormAttachment(text1,50);  9         formData.top = formAttachment;
        formData.left = formAttachment;
        // 將button1應用FormData
        Button button1 = new Button(shell, SWT.NONE);
        button1.setText("button1");
        button1.setLayoutData(formData);
        //======================華麗麗的分割線===========================

new FormAttachment(text1,50,int alignment)中alignment的設置的效果如圖所示,

表中的效果的程序就是按照上面的代碼為基礎修改"FormAttachment formAttachment = new FormAttachment(text1,50);"

這一句得到的.

FormAttachment1.java

 

public class FormAttachment1 {
    public static void main(String[] args) {
        final Display display = Display.getDefault();
        final Shell shell = new Shell();
        shell.setSize(327, 253);
        // ---------創建窗口中的其他界面組件-------------
        shell.setLayout(new FormLayout());
        Button button = new Button(shell, SWT.NONE);
        button.setText("button");
        FormData formData = new FormData();
        // 按鈕的頂端（formData.top）離shell容器的空白邊距是shell容器總體空白長度的60%
        formData.top = new FormAttachment(60, 0);
        button.setLayoutData(formData);
        // -----------------END------------------------
        shell.layout();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}

 

 

FormAttachment2.java

public class FormAttachment2 {
    public static void main(String[] args) {
        final Display display = Display.getDefault();
        final Shell shell = new Shell();
        shell.setSize(327, 253);
        // ---------創建窗口中的其他界面組件-------------
        shell.setLayout(new FormLayout());
        Text text1 = new Text(shell, SWT.BORDER);
        text1.setLayoutData(new FormData(100, 50));
        // 定義並設置FormData
        FormData formData = new FormData();
        // 以text1為基准偏移50像素
        FormAttachment formAttachment = new FormAttachment(text1, 50);
        // FormAttachment formAttachment = new FormAttachment(text1, 50,
        // SWT.LEFT);參數3的可選值包括SWT.DEFAULT、SWT.LEFT、SWT.CENTER、SWT.RIGHT、SWT.TOP、SWT.BOTTOM
        formData.top = formAttachment;
        formData.left = formAttachment;
        // 將button1應用FormData
        Button button1 = new Button(shell, SWT.NONE);
        button1.setText("button1");
        button1.setLayoutData(formData);
        // -----------------END------------------------
        shell.layout();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}