9/22/2017 0 Comments Datagrid Windows Ce Column WidthsHow to Use Tables (The Java™ Tutorials >. Creating a GUI With JFC/Swing > Using Swing Components)With the. ![]() JTable class you can display tables of data, optionally allowing the user to edit the data. JTable does not contain or cache data; it is simply a view of your data. ![]() Here is a picture of a typical table displayed within a scroll pane: The rest of this section shows you how to accomplish some common table- related tasks. Here are the topics this section covers: Try this: Click the Launch button to run Simple. Table. Demo using. Java™ Web Start (download JDK 7 or later). Or, to compile and run the example yourself, consult the example index. Building a basic GUI application step-by-step in Python with Tkinter and wxPython. Click the cell that contains "Snowboarding". The entire first row is selected, indicating that you have selected Kathy Smith's data. A special highlight indicates that the "Snowboarding" cell is editable. Generally, you begin editing a text cell by double- clicking it. Position the cursor over "First Name". Now press the mouse button and drag to the right. As you can see, users can rearrange columns in tables. Position the cursor just to the right of a column header.
Datagrid Windows Ce Column Widths In Sharepoint![]() Now press the mouse button and drag to the right or left. The column changes size, and the other columns adjust to fill the remaining space. Resize the window containing the table so that it's bigger than necessary to display the whole table. All the table cells become wider, expanding to fill the extra horizontal space. The table in. Simple. Table. Demo. java declares the column names in a String array. String[] column. Names = {"First Name". Last Name". "Sport". Years". "Vegetarian"}. Its data is initialized and stored in a two- dimensional Object array. Object[][] data = {. Kathy", "Smith". "Snowboarding", new Integer(5), new Boolean(false)}. John", "Doe". "Rowing", new Integer(3), new Boolean(true)}. Sue", "Black". "Knitting", new Integer(2), new Boolean(false)}. Jane", "White". "Speed reading", new Integer(2. Boolean(true)}. {"Joe", "Brown". Pool", new Integer(1. Boolean(false)}. Then the Table is constructed using these data and column. Names. JTable table = new JTable(data, column. Names). There are two JTable constructors that directly accept data (Simple. Table. Demo uses the first): JTable(Object[][] row. Data, Object[] column. Names)JTable(Vector row. Data, Vector column. Names)The advantage of these constructors is that they are easy to use. However, these constructors also have disadvantages: They automatically make every cell editable. They treat all data types the same (as strings). For example, if a table column has Boolean data, the table can display the data in a check box. However, if you use either of the two JTable constructors listed previously, your Boolean data is displayed as a string. You can see this difference in the Vegetarian column of the previous figure. They require that you put all of the table's data in an array or vector, which may not be appropriate for some data. For example, if you are instantiating a set of objects from a database, you might want to query the objects directly for their values, rather than copying all their values into an array or vector. If you want to get around these restrictions, you need to implement your own table model, as described in Creating a Table Model. Here is typical code for creating a scroll pane that serves as a container for a table. JScroll. Pane scroll. Pane = new JScroll. Pane(table). table. Fills. Viewport. Height(true). The two lines in this snippet do the following: The JScroll. Pane constructor is invoked with an argument that refers to the table object. This creates a scroll pane as a container for the table; the table is automatically added to the container. JTable. set. Fills. Viewport. Height is invoked to set the fills. Viewport. Height property. When this property is true the table uses the entire height of the container, even if the table doesn't have enough rows to use the whole vertical space. This makes it easier to use the table as a drag- and- drop target. The scroll pane automatically places the table header at the top of the viewport. The column names remain visible at the top of the viewing area when the table data is scrolled. If you are using a table without a scroll pane, then you must get the table header component and place it yourself. For example. container. Layout(new Border. Layout()). container. Table. Header(), Border. Layout. PAGE_START). Border. Layout. CENTER). By default, all columns in a table start out with equal width, and the columns automatically fill the entire width of the table. When the table becomes wider or narrower (which might happen when the user resizes the window containing the table), all the column widths change appropriately. When the user resizes a column by dragging its right border, then either other columns must change size, or the table's size must change. By default, the table's size remains the same, and all columns to the right of the drag point resize to accommodate space added to or removed from the column to the left of the drag point. To customize initial column widths, you can invoke set. Preferred. Width on each of your table's columns. This sets both the preferred widths of the columns and their approximate relative widths. For example, adding the following code to Simple. Table. Demo makes its third column bigger than the other columns. Table. Column column = null. Column. Model(). get. Column(i). if (i == 2) {. Preferred. Width(1. Preferred. Width(5. As the preceding code shows, each column in a table is represented by a. Table. Column object. Table. Column supplies getter and setter methods for the minimum, preferred, and maximum widths of a column, as well as a method for getting the current width. For an example of setting cell widths based on an approximation of the space needed to draw the cells' contents, see the init. Column. Sizes method in. Table. Render. Demo. When the user explicitly resizes columns, the columns' preferred widths are set such that the user- specified sizes become the columns' new current widths. However, when table itself is resized — typically because the window has resized —; the columns' preferred widths do not change. Instead, the existing preferred widths are used to calculate new column widths to fill the available space. You can change a table's resize behavior by invoking. Auto. Resize. Mode. In its default configuration, a table supports a selection that consists of one or more rows. The user can select a contiguous range of rows or an arbitrary set of rows. The last cell that the user indicated gets a special indication; in the Metal look and feel, the cell is outlined. This cell is known as the lead selection; it is sometimes called "the cell with the focus" or "the current cell". The user uses the mouse and/or keyboard to make selections, as described in the following table: Operation. Mouse Action. Keyboard Action. Select single row. Click. Up Arrow or Down Arrow. Extend contiguous selection. Shift- Click or Drag over rows. Shift- Up Arrow or Shift- Down Arrow. Add row to selection/toggle row selection. Control- Click. Move lead selection with Control- Up Arrow or Control- Down Arrow, then use Space Bar to add to selection or Control- Space Bar to toggle row selection. To see how selections work, click the Launch button to run Table. Selection. Demo using. Java™ Web Start (download JDK 7 or later). Or, to compile and run the example yourself, consult the example index. This example program presents the familiar table, and allows the user to manipulate certain JTable options. There is also a text pane that logs selection events. In the screenshot below, a user has run the program, clicked in the first row, then control- clicked in the third row. Notice the outline around the last cell clicked; this is how the Metal look and feel highlights the lead selection. Under "Selection Mode" there are a set of radio buttons. Click the one labelled "Single Selection". Now you can only select one row at a time. If you click on the "Single Interval Selection" radio button, you can select a set of rows that must be contiguous. All of the radio buttons under "Selection Mode" invoke. JTable. set. Selection. Mode. This method takes a single argument, which must be one of the following constants defined in javax. List. Selection. Model: MULTIPLE_INTERVAL_SELECTION, SINGLE_INTERVAL_SELECTION, and SINGLE_SELECTION. Returning to Table.
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